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Coal, oil, and natural gas remain the primary global energy sources even as
renewables have begun rapidly increasing.
The
Climate Change Performance Index ranks countries by greenhouse gas emissions (40% of score), renewable energy (20%), energy use (20%), and climate policy (20%).
Climate change mitigation consists of actions to limit the magnitude or rate of global warming and its related effects. This generally involves reductions in human emissions of greenhouse gases (GHGs).
Fossil fuels account for about 70% of GHG emissions. The main challenge is to eliminate the use of coal, oil and gas and substitute these fossil fuels with clean energy sources. Due to massive price drops, wind power and solar photovoltaics (PV) are increasingly out-competing oil, gas and coal though these require energy storage and extended electrical grids. Mitigation or reversal of climate change, may also be achieved by replacing petrol and diesel with electric vehicles, reforestation and forest preservation (a "carbon sink"), changes to agriculture practice and machinery, divestment from fossil fuel finance, democratic corporate governance reforms, changes to consumer laws, and implementing a green recovery after the COVID-19 pandemic. There is not yet technology for removing carbon dioxide from Earth's atmosphere, or climate engineering at safe or sufficient scale.
Almost all countries are parties to the United Nations Framework Convention on Climate Change (UNFCCC).
The ultimate objective of the UNFCCC is to stabilize atmospheric
concentrations of GHGs at a level that would prevent dangerous human
interference with the climate system.
In 2010, Parties to the UNFCCC agreed that future global warming should be limited to below 2 °C (3.6 °F) relative to the pre-industrial level. With the Paris Agreement of 2015 this was confirmed.
With the Special Report on Global Warming of 1.5 °C, the International Panel on Climate Change
has emphasized the benefits of keeping global warming below this level,
suggesting a global collective effort that may be guided by the 2015
United Nations Sustainable Development Goals.
Emissions pathways with no or limited overshoot would require rapid and
far-reaching transitions in energy, land, urban and infrastructure
including transport and buildings, and industrial systems.
The current trajectory of global greenhouse gas emissions does
not appear to be consistent with limiting global warming to below 1.5 or
2 °C. However, globally the benefits of keeping warming under 2 °C exceed the costs.
Greenhouse gas concentrations and stabilization
Stabilizing CO2 emissions at their present level would not stabilize its concentration in the atmosphere.
Stabilizing the atmospheric concentration of CO2 at a constant level would require emissions to be effectively eliminated.
The UNFCCC aims to stabilize greenhouse gas (GHG) concentrations in the atmosphere at a level where ecosystems can adapt naturally to climate change, food production is not threatened, and economic development can proceed in a sustainable fashion.
Currently human activities are adding CO2 to the atmosphere faster than natural processes can remove it.
According to a 2011 US study, stabilizing atmospheric CO2 concentrations would require anthropogenic CO2 emissions to be reduced by 80% relative to the peak emissions level.
The IPCC works with the concept of a fixed carbon emissions budget. If emissions remain on the current level of 42 GtCO
2, the carbon budget for 1.5°C could be exhausted in 2028.
The rise in temperature to that level would occur with some delay between 2030 and 2052.
Even if it was possible to achieve negative emissions in the future,
1.5°C must not be exceeded at any time to avoid the loss of ecosystems.
After leaving room for emissions for food production for 9
billion people and to keep the global temperature rise below 2 °C,
emissions from energy production and transport will have to peak almost
immediately in the developed world and decline at about 10% each year
until zero emissions are reached around 2030.
Sources of greenhouse gas emissions
With the Kyoto Protocol, the reduction of almost all anthropogenic greenhouse gases has been addressed. These gases are Carbon Dioxide (CO2), methane (CH4), nitrous oxide (N2O) and fluorinated gases (F-Gases): the hydrofluorocarbons (HFC), perfluorocarbons (PFC), and sulfur hexafluoride (SF6).
Their global warming potential
(GWP) depends on their lifetime in the atmosphere. Methane has a
relatively short atmospheric lifetime of about 10 -15 years but a high
immediate impact.
For methane, a reduction of about 30% below current emission levels
would lead to a stabilization in its atmospheric concentration, while
for N2O, an emissions reduction of more than 50% would be required. Estimations largely depend on the ability of oceans and land sinks to absorb GHGs. N2O has a high GWP and significant Ozone Depleting Potential (ODP). It is estimated that the global warming potential of N2O over 100 years is 265 times greater than CO2.
The risk of feedback effects in global warming leads to high
uncertainties in the determination of GWP values.GHG emissions are
measured in CO
2 equivalents, taking the global warming potential into account. Current emissions are estimated at 51.8 GtCO
2e, while CO
2 emissions alone make up 42 Gt per year.
Short-lived climate pollutants (SLCPs)
Short-lived
climate pollutants (SLCPs) persist in the atmosphere for a period
ranging from days to 15 years as compared to carbon dioxide which can
remain in the atmosphere for millennia. SLCPs comprise of methane, hydroflourocarbons (HFCs), tropospheric ozone and black carbon.
Reducing SLCPs emissions can cut the ongoing rate of global warming by
almost half and is a key climate strategy especially for diminishing
near-term global warming and its impacts. Cutting SLCPs may also reduce
the rate of global warming and the projected Arctic warming by
two-thirds.
Carbon dioxide (CO
2)
- Fossil fuel: oil, gas and coal are the major driver of anthropogenic global warming with annual emissions of 34.6 GtCO
2 in 2018. - Cement production is estimated 1.5 GtCO
2 - Land-use change (LUC) is the imbalance of deforestation and reforestation. Estimations are very uncertain at 3.8 GtCO
2. Wildfires cause emissions of about 7 GtCO
2 - Flaring: In crude oil production vast amounts of associated gas are commonly flared as waste or unusable gas.
Methane (CH4)
- Fossil fuel (33%) also accounts for most of the methane emissions including gas distribution, leakages and gas venting.
- Cattle (21%) account for two thirds of the methane emitted by livestock, followed by buffalo, sheep and goats
- Human waste and waste water (21%): When biomass waste in
landfills and organic substances in domestic and industrial waste water
are decomposed by bacteria in anaerobic conditions, substantial amounts
of methane are generated.
- Rice cultivation (10%) on flooded rice fields is another
agricultural source, where anaerobic decomposition of organic material
produces methane.
Nitrous oxide (N
2O)
- Most emissions by agriculture, especially meat production: cattle (droppings on pasture), fertilizers, animal manure
- Combustion of fossil and bio fuels.
- Industrial production of adipic acid and nitric acid.
F-Gases
- Switchgear in the power sector, semi-conducture manufacture, aluminium production and a large unknown source of SF6
Projections
Projections of future greenhouse gas emissions are highly uncertain. In the absence of policies to mitigate climate change, GHG emissions could rise significantly over the 21st century.
Current scientific projections warn of a 4.5 degree temperature rise in decades.
Methods and means
As the cost of reducing GHG emissions in the electricity sector appears to be lower than in other sectors, such as in the transportation
sector, the electricity sector may deliver the largest proportional
carbon reductions under an economically efficient climate policy.
Economic tools can be useful in designing climate change mitigation policies. Abolishing fossil fuel subsidies is very important but must be done carefully to avoid making poor people poorer.
Short-lived climate pollutants (SLCPs) emissions like methane may be reduced by controlling fugitive emissions from oil and gas production and controlling emissions from coal mining. Black carbon
emissions may be mitigated by upgrading coke ovens, installing
particulate filters on diesel-based engines and minimizing open burning
of biomass. Continued phase down of manufacture and use of hydroflourocarbons (HFCs) under the Montreal Protocol
will help reduce HFC emissions and concurrently improve the energy
efficiency of appliances that use HFCs like air conditioners, freezers
and refrigerators.
Other frequently discussed efficiency means include public transport, increasing fuel economy in automobiles (which includes the use of electric hybrids), charging plug-in hybrids and electric cars by low-carbon electricity, making individual changes, and changing business practices.
Replacing gasoline and diesel vehicles with electric means their
emissions would be displaced away from street level, where they cause
illness.
Another consideration is how future socioeconomic development proceeds.
Fossil fuel substitution
As most greenhouse gas emissions are due to fossil fuels, rapidly phasing out oil, gas and coal is critical. The incentive to use 100% renewable energy has been created by global warming and other ecological as well as economic concerns.
According to the IPCC, there are few fundamental technological limits
to integrating a portfolio of renewable energy technologies to meet most
of total global energy demand.
The global primary energy demand was 161,320 TWh in 2018.
This refers to electricity, transport and heating including all losses.
The primary energy demand in a low-carbon economy is difficult to
determine. In transport and electricity production, fossil fuel usage
has a low efficiency of less than 50%. Motors of vehicles produce a lot
of heat which is wasted. Electrification of all sectors and switching to
renewable energy can lower the primary energy demand significantly. On
the other hand, storage requirements, energy density issues of batteries and reconversion to electricity lower the efficiency of renewable energy.
In 2018, biomass and waste was listed with a share of 10% of
primary energy, hydro power with 3%. Wind, solar energy and other
renewables were at 2%.
Low-carbon energy sources
Wind and sun can be sources for large amounts of low-carbon energy at
competitive production costs. Solar PV module prices fell by around 80%
in the 2010s, and wind turbine prices by 30–40%. But even in combination, generation of variable renewable energy fluctuates a lot. This can be tackled by extending grids over large areas with a sufficient capacity or by using energy storage.
According to the International Renewable Energy Agency (IRENA), the deployment of renewable energy would have to be accelerated six-fold though to stay under the 2 °C target.
Load management of industrial energy consumption can help to balance the production of renewable energy production and its demand.
Electricity production by biogas and hydro power can follow the energy demand.
Solar energy
- Solar photovoltaics
has become the cheapest way to produce electric energy in many regions
of the world, with production costs down to 0.015 - 0.02 US$/KWh in
desert regions. The growth of photovoltaics is exponential and has doubled every three years since the 1990s.
- A different technology is concentrated solar power
(CSP) using mirrors or lenses to concentrate a large area of sunlight
onto a receiver. With CSP, the energy can be saved up for a few hours.
Prices in Chile are expected to fall below 0.05 US$/KWh in 2020.
- Solar water heating
makes an important and growing contribution in many countries, most
notably in China, which now has 70 percent of the global total (180
GWth). Worldwide, total installed solar water heating systems meet a
portion of the water heating needs of over 70 million households.
Wind power
Regions in the higher northern and southern latitudes have the highest potential for wind power.
Installed capacity has reached 650 GW in 2019. Offshore wind power currently has a share of about 10% of new installations. Offshore wind farms are more expensive but the units deliver more energy per installed capacity with less fluctuations.
Hydro Power
Hydroelectricity plays a leading role in countries like Brazil, Norway and China. but there are geographical limits and environmental issues.
Tidal power can be used in coastal regions.
Bioenergy
Biogas plants can provide dispatchable electricity generation, and heat when needed. A common concept is the co-fermentation of energy crops mixed with manure in agriculture.
Burning plant-derived biomass releases CO
2,
but it has still been classified as a renewable energy source in the EU
and UN legal frameworks because photosynthesis cycles the CO
2
back into new crops. How a fuel is produced, transported and processed
has a significant impact on lifecycle emissions. Transporting fuels
over long distances and excessive use of nitrogen fertilisers can reduce
the emissions savings made by the same fuel compared to natural gas by
between 15 and 50 per cent. Renewable biofuels are starting to be used in aviation.
Nuclear power
In most 1.5 °C pathways nuclear power increases its share. The main advantage is the ability to deliver large amounts of base load when renewable energy is not available. It has been repeatedly classified as a climate change mitigation technology.
On the other hand, nuclear power comes with environmental risks which could outweigh the benefits. Apart from nuclear accidents, the disposal of radioactive waste can cause damage and costs over more than one million years. Separated plutonium could be used for nuclear weapons. Public opinion about nuclear power varies widely between countries.
As of 2019 the cost of extending nuclear power plant lifetimes is competitive with other electricity generation technologies, including new solar and wind projects.
New projects are reported to be highly dependent on public subsidies.
Nuclear fusion research, in the form of the International Thermonuclear Experimental Reactor is underway but fusion is not likely to be commercially widespread before 2050.
Carbon neutral and negative fuels
Fossil fuel may be phased-out with carbon-neutral and carbon-negative pipeline and transportation fuels created with power to gas and gas to liquids technologies.
Natural gas
Natural gas, which is mostly methane, is viewed as a bridge fuel since it produces about half as much CO
2 as burning coal. Gas-fired power plants can provide the required flexibility in electricity production in combination wind and solar energy.
But methane is itself a potent greenhouse gas, and it currently leaks
from production wells, storage tanks, pipelines, and urban distribution
pipes for natural gas. In a low-carbon scenario, gas-fueled power plants could still continue operation if methane was produced using power-to-gas technology with renewable energy sources.
Energy storage
Wind energy and photovoltaics can deliver large amounts of electric
energy but not at any time and place. One approach is the conversation
into storable forms of energy. This generally leads to losses in
efficiency. A study by Imperial College London calculated the lowest levelised cost of different systems for mid-term and seasonal storage. In 2020, pumped hydro (PHES), compressed air (CAES) and Li-on batteries are most cost effective depending on charging rhythm. For 2040, a more significant role for Li-on and hydrogen is projected.
- Hydrogen may be useful for seasonal energy storage.
The low efficiency of 30% must improve dramatically before hydrogen
storage can offer the same overall energy efficiency as batteries.
For the electricity grid a German study estimated high costs of 0.176
€/KWh for reconversion concluding that substituting the electricity grid
expansion entirely with hydrogen reconversion systems does not make
sense from an economic standpoint.
The concept of solar hydrogen is discussed for remote desert projects
where grid connections to demand centers are not available. Because it has more energy per unit volume sometimes it may be better to use hydrogen in ammonia.
Super grids
Long-distance power lines help to minimize storage requirements. A
continental transmission network can smoothen local variations of wind
energy. With a global grid, even photovoltaics could be available all
day and night. The strongest High-voltage direct current (HVDC) connections are quoted with losses of only 1.6% per 1000 km
with a clear advantage compared to AC. HVDC is currently only used for
point-to-point connections. Meshed HVDC grids are reported to be
ready-to-use in Europe and to be in operation in China by 2022.
China has built many HVDC connections within the country and
supports the idea of a global, intercontinental grid as a backbone
system for the existing national AC grids. A super grid in the US in combination with renewable energy could reduce GHG emissions by 80%.
Smart grid and load management
Instead of expanding grids and storage for more power, there are a
variety of ways to affect the size and timing of electricity demand on
the consumer side. Identifying and shifting electrical loads can reduce
power bills by taking advantage of lower off-peak rates and flatten
demand peaks. Traditionally, the energy system has treated consumer
demand as fixed and used centralised supply options to manage variable
demand. Now, better data systems and emerging onsite storageand
generation technologies can combine with advanced, automated demand
control software to pro-actively manage demand and respond to energy
market prices.
Time of use
metering is a common way to motivate electricity users to reduce their
peak load consumption. For instance, running dishwashers and laundry at
night after the peak has passed, reduces electricity costs.
Dynamic demand
plans have devices passively shut off when stress is sensed on the
electrical grid. This method may work very well with thermostats, when
power on the grid sags a small amount, a low power temperature setting
is automatically selected reducing the load on the grid. For instance
millions of refrigerators reduce their consumption when clouds pass over
solar installations. Consumers need to have a smart meter in order for the utility to calculate credits.
Demand response
devices can receive all sorts of messages from the grid. The message
could be a request to use a low power mode similar to dynamic demand, to
shut off entirely during a sudden failure on the grid, or notifications
about the current and expected prices for power. This allows electric
cars to recharge at the least expensive rates independent of the time of
day. Vehicle-to-grid uses a car's battery or fuel cell to supply the grid temporarily.
Decarbonization of transport
Between a quarter and three-quarters of cars on the road by 2050 are forecast to be electric.
Hydrogen can be a solution for long-distance transport by trucks and hydrogen-powered ships where batteries alone are too heavy.
Passenger cars using hydrogen are already produced in small numbers.
While being more expensive than battery powered cars, they can refuel
much faster, offering higher ranges up to 700 km.
The main disadvantage of hydrogen is the low efficiency of only 30%.
When used for vehicles, more than twice as much energy is needed
compared to a battery powered electric car.
Although aviation biofuel is used somewhat, as of 2019 decarbonisation of aviation by 2050 is claimed to be "really difficult".
Decarbonization of heating
The buildings sector accounts for 23% of global energy-related CO2 emissions About half of the energy is used for space and water heating.
A combination of electric heat pumps and building insolation can reduce
the primary energy demand significantly. Generally, electrification of
heating would only reduce GHG emissions if the electric power comes from
low-carbon sources. A fossil-fuel power station may only deliver 3
units of electrical energy for every 10 units of fuel energy released.
Electrifying heating loads may also provide a flexible resource that can
participate in demand response to integrate variable renewable resources into the grid.
Heat pump
Outside unit of an air-source heat pump
A modern heat pump typically produces around three times more thermal
energy than electrical energy consumed, giving an effective efficiency
of 300%, depending on the coefficient of performance. It uses an electrically driven compressor to operate a refrigeration cycle
that extracts heat energy from outdoor air and moves that heat to the
space to be warmed. In the summer months, the cycle can be reversed for air conditioning.
In areas with average winter temperatures well below freezing, ground
source heat pumps are more efficient than air-source heat pumps. The
high purchase price of a heat pump compared to resistance heaters may be
offset when air conditioning is also needed.
With a market share of 30% and clean electricity, heat pumps could reduce global CO
2 emissions by 8% annually. Using ground source heat pumps could reduce around 60% of the primary energy demand and 90% of CO
2 emissions of natural gas boilers in Europe in 2050 and make handling high shares of renewable energy easier.
Using surplus renewable energy in heat pumps is regarded as the most
effective household means to reduce global warming and fossil fuel
depletion.
Electric resistant heating
Radiant heaters in households are cheap and widespread but less efficient than heat pumps. In areas like Norway, Brazil, and Quebec
that have abundant hydroelectricity, electric heat and hot water are
common. Large scale hot water tanks can be used for demand-side
management and store variable renewable energy over hours or days.
Energy conservation
Reducing energy use is seen as a key solution to the problem of reducing greenhouse gas emissions. According to the International Energy Agency, improved energy efficiency in buildings, industrial processes and transportation could reduce the world's energy needs in 2050 by one third, and help control global emissions of greenhouse gases.
Energy efficiency
Energy efficiency means using the least amount of energy to perform a
task or the ability of a piece of equipment to use the least amount of
energy to perform a task. To conserve energy or reduce electricity
costs, individual consumers or businesses may deliberately purchase
energy efficient products that use refrigerants with low global warming
potential (GWP) or products that are ENERGY STAR certified. In general, the more the number of ENERGY STARS, the more efficient the product is. A procurement toolkit
to assist individuals and businesses buy energy efficient products that
use low GWP refrigerants was developed by the Sustainable Purchasing
Leadership Council
and is available for use. Products with refrigerants include household
refrigerators and freezers, commercial stand-alone refrigerators and
freezers, lab-grade refrigerators and freezers, commercial ice makers,
vending machines, water dispensers, water coolers, room air conditioners
and vehicles. Efficiency covers a wide range of means from building insulation to public transport. The cogeneration of electric energy and district heat also improves efficiency.
Lifestyle and behavior
The IPCC Fifth Assessment Report
emphasises that behaviour, lifestyle, and cultural change have a high
mitigation potential in some sectors, particularly when complementing
technological and structural change.
Examples would be heating a room less or driving less. In general,
higher consumption lifestyles have a greater environmental impact. The
sources of emissions have also been shown to be highly unevenly
distributed, with 45% of emissions coming from the lifestyles of just
10% of the global population.
Several scientific studies have shown that when relatively rich people
wish to reduce their carbon footprint, there are a few key actions they
can take such as living car-free (2.4 tonnes CO2), avoiding one round-trip transatlantic flight (1.6 tonnes) and eating a plant-based diet (0.8 tonnes).
These appear to differ significantly from the popular advice for
"greening" one's lifestyle, which seem to fall mostly into the
"low-impact" category: Replacing a typical car with a hybrid (0.52
tonnes); Washing clothes in cold water (0.25 tonnes); Recycling (0.21
tonnes); Upgrading light bulbs (0.10 tonnes); etc. The researchers found
that public discourse on reducing one's carbon footprint overwhelmingly
focuses on low-impact behaviors, and that mention of the high-impact
behaviors is almost non-existent in the mainstream media, government
publications, school textbooks, etc.
Scientists also argue that piecemeal behavioural changes like
re-using plastic bags are not a proportionate response to climate
change. Though being beneficial, these debates would drive public focus
away from the requirement for an energy system change of unprecedented
scale to decarbonise rapidly.
Dietary change
Overall, food accounts for the largest share of consumption-based GHG
emissions with nearly 20% of the global carbon footprint, followed by
housing, mobility, services, manufactured products, and construction.
Food and services are more significant in poor countries, while mobility
and manufactured goods are more significant in rich countries.
The widespread adoption of a vegetarian diet could cut food-related greenhouse gas emissions by 63% by 2050.
China introduced new dietary guidelines in 2016 which aim to cut meat
consumption by 50% and thereby reduce greenhouse gas emissions by 1 billion tonnes by 2030.
A 2016 study concluded that taxes on meat and milk could simultaneously
result in reduced greenhouse gas emissions and healthier diets. The
study analyzed surcharges of 40% on beef and 20% on milk and suggests
that an optimum plan would reduce emissions by 1 billion tonnes per year.
Modal shift
Heavyweight, large personal vehicles (such as cars) require a lot of energy to move and take up much urban space. Several alternatives modes of transport are available to replace these. The European Union has made smart mobility part of its European Green Deal and in smart cities, smart mobility is also important.
Carbon sinks and removal
World protected area map with total percentage of each country under protection.
A carbon sink
is a natural or artificial reservoir that accumulates and stores some
carbon-containing chemical compound for an indefinite period, such as a
growing forest. Carbon dioxide removal on the other hand is a permanent removal of carbon dioxide out of the atmosphere. Examples are direct air capture, enhanced weathering technologies such as storing it in geologic formations underground and biochar. These processes are sometimes considered variations of sinks or mitigation, and sometimes as geoengineering. In combination with other mitigation measures, carbon sinks and removal are crucial for meeting the 2 degree target.
The Antarctic Climate and Ecosystems Cooperative Research Centre
(ACE-CRC) notes that one third of humankind's annual emissions of CO
2 are absorbed by the oceans. However, this also leads to ocean acidification, which may harm marine life.
Acidification lowers the level of carbonate ions available for
calcifying organisms to form their shells. These organisms include
plankton species that contribute to the foundation of the Southern Ocean food web. However acidification may impact on a broad range of other physiological and ecological processes, such as fish respiration, larval development and changes in the solubility of both nutrients and toxins.
Conserving areas by protecting areas can boost the carbon sequestration capacity. The European Union, through the EU Biodiversity Strategy for 2030
targets to protect 30% of the sea territory and 30% of the land
territory by 2030. Also, Campaign for Nature's 30x30 for Nature Petition
tries to let governments agree to the same goal during the Convention
on Biodiversity COP15 Summit. The One Earth Climate Model advises a protection
of 50% of our lands and oceans. It also stresses the importance of rewilding, like other reports. The reason being that predators keep the population of herbivores in check (which reduce the biomass of vegetation), and also impact their feeding behavior.
Proforestation, avoided deforestation, reforestation and afforestation
Transferring
land rights to indigenous inhabitants is argued to efficiently conserve forests.
Almost 20 percent (8 GtCO2/year) of total greenhouse-gas emissions were from deforestation in 2007. It is estimated that avoided deforestation reduces CO2 emissions at a rate of 1 tonne of CO2 per $1–5 in opportunity costs from lost agriculture. Reforestation, which is restocking of depleted forests, could save at least another 1 GtCO2/year, at an estimated cost of $5–15/tCO2.
According to research conducted at ETH Zurich, restoring all degraded
forests all over the world could capture about 205 billion tons of
carbon in total (which is about 2/3rd of all carbon emissions, bringing
global warming down to below 2 °C). Afforestation
is where there was previously no forest. According to research by Tom
Crowther et al., there is still enough room to plant an additional 1.2
trillion trees. This amount of trees would cancel out the last 10 years
of CO2 emissions and sequester 160 billion tons of carbon. This vision is being executed by the Trillion Tree Campaign. Other studies
have found large-scale afforestation can do more harm than good or such
plantations are estimated to have to be prohibitively massive to reduce
emissions. Proforestation
which is maintaining or growing existing forests intact to their
ecological potential, maintains and optimizes carbon sequestration or
carbon dioxide removal from the atmosphere while limiting climate
change. Proforestation is a nature-based solution.
Transferring rights over land from public domain to its
indigenous inhabitants, who have had a stake for millennia in preserving
the forests that they depend on, is argued to be a cost-effective
strategy to conserve forests. This includes the protection of such rights entitled in existing laws, such as India's Forest Rights Act. The transferring of such rights in China, perhaps the largest land reform in modern times, has been argued to have increased forest cover.
Granting title of the land has shown to have two or three times less
clearing than even state run parks, notably in the Brazilian Amazon. Conservation methods that exclude humans and even evict inhabitants
from protected areas (called "fortress conservation") often lead to more
exploitation of the land as the native inhabitants then turn to work
for extractive companies to survive.
With increased intensive agriculture and urbanization, there is an increase in the amount of abandoned farmland. By some estimates, for every acre of original old-growth forest cut down, more than 50 acres of new secondary forests
are growing, even though they do not have the same biodiversity as the
original forests and original forests store 60% more carbon than these
new secondary forests. According to a study in Science, promoting regrowth on abandoned farmland could offset years of carbon emissions.
Research by the university ETH Zurich estimates that Russia, the United
States and Canada have the most land suitable for reforestation.
Avoided desertification
Restoring grasslands stores CO2
from the air in plant material. Grazing livestock, usually not left to
wander, would eat the grass and would minimize any grass growth.
However, grass left alone would eventually grow to cover its own growing
buds, preventing them from photosynthesizing and the dying plant would
stay in place.
A method proposed to restore grasslands uses fences with many small
paddocks and moving herds from one paddock to another after a day or two
in order to mimic natural grazers and allowing the grass to grow
optimally.
Additionally, when part of the leaf matter is consumed by an animal in
the herd, a corresponding amount of root matter is sloughed off too as
it would not be able to sustain the previous amount of root matter and
while most of the lost root matter would rot and enter the atmosphere,
part of the carbon is sequestered into the soil.
It is estimated that increasing the carbon content of the soils in the
world's 3.5 billion hectares of agricultural grassland by 1% would
offset nearly 12 years of CO2 emissions. Allan Savory, as part of holistic management, claims that while large herds are often blamed for desertification,
prehistoric lands supported large or larger herds and areas where herds
were removed in the United States are still desertifying.
Additionally, the global warming induced thawing of the permafrost, which stores about two times the amount of the carbon currently released in the atmosphere, releases the potent greenhouse gas, methane, in a positive feedback cycle that is feared to lead to a tipping point called runaway climate change.
While the permafrost is about 14 degrees Fahrenheit, a blanket of snow
insulates it from the colder air above which could be 40 degrees below
zero Fahrenheit. A method proposed to prevent such a scenario is to bring back large herbivores such as seen in Pleistocene Park,
where they keep the ground cooler by reducing snow cover height by
about half and eliminating shrubs and thus keeping the ground more
exposed to the cold air.
Protecting healthy soils and recovering damaged soils could
remove 5.5 billion tons of carbon dioxide from the atmosphere annually,
which is approximately equal to the annual emissions of the USA.
Blue carbon
Estimates of the economic value of blue carbon ecosystems per hectare. Based on 2009 data from UNEP/GRID-Arendal.
Blue carbon refers to carbon dioxide removed from the atmosphere by the world's coastal ocean ecosystems, mostly mangroves, salt marshes, seagrasses and macroalgae, through plant growth and the accumulation and burial of organic matter in the soil.
Historically the ocean, atmosphere, soil, and terrestrial forest ecosystems have been the largest natural carbon (C) sinks. New research on the role of vegetated coastal ecosystems has highlighted their potential as highly efficient C sinks, and led to the scientific recognition of the term "Blue Carbon".
"Blue Carbon" designates carbon that is fixed via coastal ocean
ecosystems, rather than traditional land ecosystems, like forests.
Although the ocean's vegetated habitats cover less than 0.5% of the seabed, they are responsible for more than 50%, and potentially up to 70%, of all carbon storage in ocean sediments. Mangroves, salt marshes and seagrasses
make up the majority of the ocean's vegetated habitats but only equal
0.05% of the plant biomass on land. Despite their small footprint, they
can store a comparable amount of carbon per year and are highly
efficient carbon sinks. Seagrasses, mangroves and salt marshes can capture carbon dioxide (CO
2) from the atmosphere by sequestering the C in their underlying sediments, in underground and below-ground biomass, and in dead biomass.
In plant biomass such as leaves, stems, branches or roots, blue carbon
can be sequestered for years to decades, and for thousands to millions
of years in underlying plant sediments. Current estimates of long-term
blue carbon C burial capacity are variable, and research is ongoing. Although vegetated coastal ecosystems cover less area and have less aboveground biomass than
terrestrial plants they have the potential to impact longterm C sequestration, particularly in sediment sinks.
One of the main concerns with Blue Carbon is the rate of loss of these
important marine ecosystems is much higher than any other ecosystem on
the planet, even compared to rainforests. Current estimates suggest a
loss of 2-7% per year, which is not only lost carbon sequestration, but
also lost habitat that is important for managing climate, coastal
protection, and health.
Peatlands
Peat extraction in
East Frisia, Germany. Peat extraction degrades peatland and is possible as many peatlands are currently not protected.
Peatland globally
stores up to 550 gigatonnes of carbon, representing 42% of all soil
carbon and exceeds the carbon stored in all other vegetation types,
including the world's forests. Across the world, peat covers just 3% of the land’s surface, but stores one-third of the Earth’s soil carbon.
Restoration of degraded peatlands can be done by blocking drainage channels in the peatland, and allowing natural vegetation to recover.
Carbon capture and storage
Schematic
showing both terrestrial and geological sequestration of carbon dioxide
emissions from a large point source, for example burning natural gas
Carbon capture and storage (CCS) is a method to mitigate climate change by capturing carbon dioxide (CO2)
from large point sources such as power plants and subsequently storing
it away safely instead of releasing it into the atmosphere. The IPCC
estimates that the costs of halting global warming would double without
CCS. The International Energy Agency says CCS is "the most important single new technology for CO2 savings" in power generation and industry. Norway's Sleipner gas field, beginning in 1996, stores almost a million tons of CO2 a year to avoid penalties in producing natural gas with unusually high levels of CO2. According to a Sierra Club analysis, the US Kemper Project,
which was due to be online in 2017, is the most expensive power plant
ever built for the watts of electricity it will generate.
Enhanced weathering
Geoengineering
IPCC (2007) concluded that geoengineering options, such as ocean fertilization to remove CO2 from the atmosphere, remained largely unproven. It was judged that reliable cost estimates for geoengineering had not yet been published.
Chapter 28 of the National Academy of Sciences report Policy Implications of Greenhouse Warming: Mitigation, Adaptation, and the Science Base
(1992) defined geoengineering as "options that would involve
large-scale engineering of our environment in order to combat or
counteract the effects of changes in atmospheric chemistry."
They evaluated a range of options to try to give preliminary answers to
two questions: can these options work and could they be carried out
with a reasonable cost. They also sought to encourage discussion of a
third question — what adverse side effects might there be. Increasing
ocean absorption of carbon dioxide (carbon sequestration) and screening
out some sunlight were evaluated. NAS also argued "Engineered
countermeasures need to be evaluated but should not be implemented
without broad understanding of the direct effects and the potential side
effects, the ethical issues, and the risks." In July 2011 a report by the United States Government Accountability Office on geoengineering found that "[c]limate engineering technologies do not now offer a viable response to global climate change."
Carbon dioxide removal
Carbon dioxide removal
has been proposed as a method of reducing the amount of radiative
forcing. A variety of means of artificially capturing and storing
carbon, as well as of enhancing natural sequestration processes, are
being explored. The main natural process is photosynthesis by plants and single-celled organisms. Artificial processes vary, and concerns have been expressed about the long-term effects of some of these processes.
It is notable that the availability of cheap energy and appropriate sites for geological storage of carbon may make carbon dioxide air capture viable commercially. It is, however, generally expected that carbon dioxide air capture may be uneconomic when compared to carbon capture and storage from major sources — in particular, fossil fuel powered power stations, refineries, etc. As in the case of the US Kemper Project with carbon capture, costs of energy produced will grow significantly. CO2 can also be used in commercial greenhouses, giving an opportunity to kick-start the technology.
Solar radiation management
Proposed solar radiation management using a tethered balloon to inject sulfate aerosols into the stratosphere.
Solar radiation management (SRM), or solar geoengineering, is a type of climate engineering in which sunlight (solar radiation) is reflected to limit or reverse global warming. Proposed methods include increasing the planetary albedo, for example with stratospheric sulfate aerosol injection.
Restorative methods have also been proposed regarding the protection of
natural heat reflectors including sea ice, snow, and glaciers.
Their principal advantages as an approach to climate engineering is the
speed with which they can be deployed and become fully active, their
low financial cost, and the reversibility of their direct climatic
effects.
Solar radiation management could serve as a temporary response while
levels of greenhouse gases in the atmosphere are reduced through the
reduction of greenhouse gas emissions and
carbon dioxide removal. SRM would not reduce
greenhouse gas concentrations in the
atmosphere, and thus does not address problems such as
ocean acidification caused by excess
carbon dioxide (CO
2).
However, SRM has been shown in climate models to be capable of reducing
global average temperatures to pre-industrial levels, therefore SRM can
prevent the
climate change caused by global warming.
By Sector
Agriculture
Managed grazing methods are argued to be able to restore grasslands, thereby significantly decreasing atmospheric CO2 levels.
An agriculture that mitigates climate change is generally called sustainable agriculture,
defined as an agriculture that "meets society's food and textile needs
in the present without compromising the ability of future generations to
meet their own needs".
One mode of agriculture considered as relatively sustainable is regenerative agriculture.
It includes several methods, the main of which are: conservation
tillage, diversity, rotation and cover crops, minimizing physical
disturbance, minimizing the usage of chemicals. It has other benefits
like improving the state of the soil and consequently yields. Some of
the big agricultural companies like General Mills and a lot of farms support it.
In the United States, soils account for about half of agricultural greenhouse gas emissions while agriculture, forestry and other land use emits 24%. Globally, livestock is responsible for 18 percent of greenhouse gas emissions, according to FAO's report called "Livestock's Long Shadow: Environmental Issues and Options"
The US EPA says soil management practices that can reduce the emissions of nitrous oxide (N
2O) from soils include fertilizer usage, irrigation, and tillage. Manure management and rice cultivation also produce gaseous emissions.
Important mitigation options for reducing the greenhouse gas emissions from livestock (especially ruminants) include genetic selection introduction of methanotrophic bacteria into the rumen, diet modification and grazing management. Other options include just using ruminant-free alternatives instead, such as milk substitutes and meat analogues. Non-ruminant livestock (e.g. poultry) generates far fewer emissions.
Methods that enhance carbon sequestration in soil include no-till farming, residue mulching, cover cropping, and crop rotation, all of which are more widely used in organic farming than in conventional farming.
Because only 5% of US farmland currently uses no-till and residue
mulching, there is a large potential for carbon sequestration.
A 2015 study found that farming can deplete soil carbon and
render soil incapable of supporting life; however, the study also showed
that conservation farming can protect carbon in soils, and repair damage over time. The farming practice of cover crops has been recognized as climate-smart agriculture.
Best management practices for European soils were described to be
increase soil organic carbon: conversion of arable land to grassland,
straw incorporation, reduced tillage, straw incorporation combined with
reduced tillage, ley cropping system and cover crops.
In terms of prevention, vaccines are being developed in Australia to reduce the significant global warming contributions from methane released by livestock via flatulence and eructation.
A project to mitigate climate change with agriculture was
launched in 2019 by the "Global EverGreening Alliance". The target is to
sequester carbon from the atmosphere with Agroforestry. By 2050 the restored land should sequestrate 20 billion of carbon annually
Transport
Transportation emissions account for roughly 1/4 of emissions worldwide
and are even more important in terms of impact in developed nations
especially in North America and Australia. Many citizens of countries
like the United States and Canada who drive personal cars often, see
well over half of their climate change impact stemming from the
emissions produced from their cars.
Modes of mass transportation such as bus, light rail (metro, subway,
etc.), and long-distance rail are far and away the most energy-efficient
means of motorized transportation for passengers, able to use in many
cases over twenty times less energy per person-distance than a personal
automobile. Modern energy-efficient technologies, such as electric vehicles and carbon-neutral synthetic gasoline and jet fuel may also help to reduce the consumption of petroleum, land use changes and emissions of carbon dioxide. Utilizing rail transport, especially electric rail, over the far less efficient air transport and truck transport
significantly reduces emissions. With the use of electric trains and cars in transportation there is the opportunity to run them with low-carbon power, producing far fewer emissions.
Urban planning
Bicycles have almost no
carbon footprint compared to cars, and canal transport may represent a positive option for certain types of freight in the 21st century.
Effective urban planning to reduce sprawl
aims to decrease Vehicle Miles Travelled (VMT), lowering emissions from
transportation. Personal cars are extremely inefficient at moving
passengers, while public transport
and bicycles are many times more efficient (as is the simplest form of
human transportation, walking). All of these are encouraged by
urban/community planning and are an effective way to reduce greenhouse
gas emissions. Inefficient land use
development practices have increased infrastructure costs as well as
the amount of energy needed for transportation, community services, and
buildings.
At the same time, a growing number of citizens and government
officials have begun advocating a smarter approach to land use planning.
These smart growth
practices include compact community development, multiple
transportation choices, mixed land uses, and practices to conserve green
space. These programs offer environmental, economic, and
quality-of-life benefits; and they also serve to reduce energy usage and
greenhouse gas emissions.
Approaches such as New Urbanism and transit-oriented development seek to reduce distances travelled, especially by private vehicles, encourage public transit and make walking and cycling more attractive options. This is achieved through "medium-density", mixed-use planning and the concentration of housing within walking distance of town centers and transport nodes.
Smarter growth land use policies have both a direct and indirect
effect on energy consuming behavior. For example, transportation energy
usage, the number one user of petroleum fuels, could be significantly
reduced through more compact and mixed use land development patterns,
which in turn could be served by a greater variety of non-automotive
based transportation choices.
Building design
Emissions from housing are substantial, and government-supported energy efficiency programmes can make a difference.
New buildings can be constructed using passive solar building design, low-energy building, or zero-energy building techniques, using renewable heat sources. Existing buildings can be made more efficient through the use of insulation, high-efficiency appliances (particularly hot water heaters and furnaces), double- or triple-glazed gas-filled windows, external window shades, and building orientation and siting. Renewable heat sources such as shallow geothermal and passive solar
energy reduce the amount of greenhouse gasses emitted. In addition to
designing buildings which are more energy-efficient to heat, it is
possible to design buildings that are more energy-efficient to cool by
using lighter-coloured, more reflective materials in the development of
urban areas (e.g. by painting roofs white) and planting trees. This saves energy because it cools buildings and reduces the urban heat island effect thus reducing the use of air conditioning.
Societal controls
Another method being examined is to make carbon a new currency by introducing tradeable "personal carbon credits".
The idea being it will encourage and motivate individuals to reduce
their 'carbon footprint' by the way they live. Each citizen will receive
a free annual quota of carbon that they can use to travel, buy food,
and go about their business. It has been suggested that by using this
concept it could actually solve two problems; pollution and poverty, old
age pensioners will actually be better off because they fly less often,
so they can cash in their quota at the end of the year to pay heating
bills and so forth.
Population
Various organizations promote human population planning as a means for mitigating global warming. Proposed measures include improving access to family planning and reproductive health care and information, reducing natalistic politics,
public education about the consequences of continued population growth,
and improving access of women to education and economic opportunities.
According to a 2017 study published in Environmental Research Letters,
having one less child would have a much more substantial effect on
greenhouse gas emissions compared with for example living car free or
eating a plant-based diet. However this has been criticised: both as a category mistake for assigning descendants emissions to their ancestors and for the very long timescale of reductions.
Population control efforts are impeded by there being somewhat of
a taboo in some countries against considering any such efforts. Also, various religions discourage or prohibit some or all forms of birth control.
Population size has a vastly different per capita effect on global
warming in different countries, since the per capita production of
anthropogenic greenhouse gases varies greatly by country.
Costs and benefits
Globally the benefits of keeping warming under 2 °C exceed the costs. However some consider cost–benefit analysis
unsuitable for analysing climate change mitigation as a whole, but
still useful for analysing the difference between a 1.5 °C target and 2
°C. The OECD has been applying economic models and qualitative assessments to inform on climate change benefits and tradeoffs.
Costs
One way of
estimating the cost of reducing emissions is by considering the likely
costs of potential technological and output changes. Policy makers can
compare the marginal abatement costs
of different methods to assess the cost and amount of possible
abatement over time. The marginal abatement costs of the various
measures will differ by country, by sector, and over time. Mitigation costs will vary according to how and when emissions are cut: early, well-planned action will minimise the costs.
Many economists estimate the cost of climate change mitigation at between 1% and 2% of GDP. In 2019, scientists from Australia, and Germany
presented the "One Earth Climate Model" showing how temperature
increase can be limited to 1.5 °C for 1.7 trillion dollars a year.
According to this study, a global investment of approximately $1.7 trillion per year would be needed to keep global warming below 1.5°C.
The method used by the One Earth Climate Model does not resort to
dangerous geo-engineering methods. Whereas this is a large sum, it is
still far less than the subsidies
governments currently provided to the ailing fossil fuel industry,
estimated at more than $5 trillion per year by the International
Monetary Fund.
Benefits
By addressing climate change, we can avoid the costs associated with the effects of climate change.
According to the Stern Review,
inaction can be as high as the equivalent of losing at least 5% of
global gross domestic product (GDP) each year, now and forever (up to
20% of the GDP or more when including a wider range of risks and
impacts), whereas mitigating climate change will only cost about 2% of the GDP.
Also, delaying to take significant reductions in greenhouse gas
emissions may not be a good idea, when seen from a financial
perspective.
The research organization Project Drawdown identified global climate solutions and ranked them according to their benefits. Early deaths due to fossil fuel air pollution with a temperature rise to 2 °C cost more globally than mitigation would: and in India cost 4 to 5 times more.
Sharing
One of
the aspects of mitigation is how to share the costs and benefits of
mitigation policies. In terms of the politics of mitigation, the
UNFCCC's ultimate objective is to stabilize concentrations of GHG in the
atmosphere at a level that would prevent "dangerous" climate change (Rogner et al., 2007).
Rich people tend to emit more GHG than poor people. Activities of the poor that involve emissions of GHGs are often associated with basic needs, such as cooking. For richer people, emissions tend to be associated with things such as eating beef, cars, frequent flying, and home heating. The impacts of cutting emissions could therefore have different impacts on human welfare according to wealth.
Distributing emissions abatement costs
There have been different proposals on how to allocate responsibility for cutting emissions (Banuri et al., 1996, pp. 103–105):
- Egalitarianism:
this system interprets the problem as one where each person has equal
rights to a global resource, i.e., polluting the atmosphere.
- Basic needs: this system would have emissions allocated according to basic needs, as defined according to a minimum level of consumption.
Consumption above basic needs would require countries to buy more
emission rights. From this viewpoint, developing countries would need to
be at least as well off under an emissions control regime as they would
be outside the regime.
- Proportionality and polluter-pays principle: Proportionality reflects the ancient Aristotelian
principle that people should receive in proportion to what they put in,
and pay in proportion to the damages they cause. This has a potential
relationship with the "polluter-pays principle", which can be
interpreted in a number of ways:
- Historical responsibilities: this asserts that allocation
of emission rights should be based on patterns of past emissions.
Two-thirds of the stock of GHGs in the atmosphere at present is due to
the past actions of developed countries (Goldemberg et al., 1996, p. 29).
- Comparable burdens and ability to pay: with this approach,
countries would reduce emissions based on comparable burdens and their
ability to take on the costs of reduction. Ways to assess burdens
include monetary costs per head of population, as well as other, more
complex measures, like the UNDP's Human Development Index.
- Willingness to pay: with this approach, countries take on emission reductions based on their ability to pay along with how much they benefit from reducing their emissions.
Specific proposals
- Ad hoc: Lashof (1992) and Cline (1992) (referred to by Banuri et al., 1996, p. 106), for example, suggested that allocations based partly on GNP
could be a way of sharing the burdens of emission reductions. This is
because GNP and economic activity are partially tied to carbon
emissions.
- Equal per capita entitlements: this is the most widely cited method of distributing abatement costs, and is derived from egalitarianism (Banuri et al.,
1996, pp. 106–107). This approach can be divided into two categories.
In the first category, emissions are allocated according to national
population. In the second category, emissions are allocated in a way
that attempts to account for historical (cumulative) emissions.
- Status quo: with this approach, historical emissions are
ignored, and current emission levels are taken as a status quo right to
emit (Banuri et al., 1996, p. 107). An analogy for this approach can be made with fisheries, which is a common, limited resource. The analogy would be with the atmosphere, which can be viewed as an exhaustible natural resource (Goldemberg et al., 1996, p. 27). In international law,
one state recognized the long-established use of another state's use of
the fisheries resource. It was also recognized by the state that part
of the other state's economy was dependent on that resource.
Governmental and intergovernmental action
Bringing
down emissions of greenhouse gases asks a good deal of people, not
least that they accept the science of climate change. It requires them
to make sacrifices today so that future generations will suffer less,
and to weigh the needs of people who are living far away.
In 2019 a report was published by the United Nations
saying that to limit the temperature rise to 2 °C, the world will need
to cut emissions by 2.7% each year from 2020 to 2030, and triple the
climate targets. To limit the temperature rise to 1.5 °C the world would
need to cut emissions by 7.6% each year from 2020 to 2030 and increase
its climate commitments five-fold. Even if all the Paris Agreement pledges as they are in 2019, are fulfilled the temperature will rise by 3.2 degrees this century.
A report published in September 2019 before the 2019 UN Climate Action Summit
says, that the full implementation of all pledges made by international
coalitions, countries, cities, regions and businesses (not only those
in the Paris Agreement) will be sufficient to limit temperature rise to 2
degrees but not to 1.5 degrees. Additional pledges were made in the September climate summit and in December. All the information about all climate pledges is sent to the Global Climate Action Portal - Nazca. The scientific community is checking their fulfillment.
Paris agreement and Kyoto Protocol
The main current international agreement on combating climate change is the Paris agreement.
The Paris Agreement's long-term temperature goal is to keep the
increase in global average temperature to well below 2°C above
pre-industrial levels; and to pursue efforts to limit the increase to
1.5°C. Each country must determine, plan, and regularly report on the
contribution that it undertakes to mitigate global warming. Climate change mitigation measures can be written down in national environmental policy documents like the nationally determined contributions (NDC).
The Paris agreement succeeds the 1997 Kyoto Protocol which expires in 2020, and is an amendment to the United Nations Framework Convention on Climate Change (UNFCCC). Countries that ratified the Kyoto protocol committed to reduce their emissions of carbon dioxide and five other greenhouse gases, or engage in emissions trading if they maintain or increase emissions of these gases.
How well each individual country is on track to achieving its Paris agreement commitments can be followed on-line.
Additional commitments
Except
the main agreements there are many additional pledges made by
international coalitions, countries, cities, regions and businesses.
According to a report published in September 2019 before the 2019 UN Climate Action Summit,
full implementation of all pledges, including those in the Paris
Agreement, will be sufficient to limit temperature rise to 2 degrees but
not to 1.5 degrees. After the report was published, additional pledges were made in the September climate summit and in December of that year.
All the information about the pledges is collected and analyzed in the Global Climate Action (portal), what is facilitating to the scientific community to check their fulfillment
Temperature targets
Human activities are estimated to have caused approximately 1.0 °C of global warming above
pre-industrial levels, with a likely range of 0.8 °C to 1.2 °C.
There is disagreement among experts over whether or not the 2 °C target can be met.
- Official long-term target of 1.5 °C
In 2015, two official UNFCCC scientific expert bodies came to the
conclusion that, "in some regions and vulnerable ecosystems, high risks
are projected even for warming above 1.5 °C".
This expert position was, together with the strong diplomatic voice of
the poorest countries and the island nations in the Pacific, the driving
force leading to the decision of the Paris Conference 2015, to lay down this 1.5 °C long-term target on top of the existing 2 °C goal.
Encouraging use changes
Emissions tax
An emissions tax on greenhouse gas emissions requires emitters to pay
a fee, charge or tax for every tonne of greenhouse gas released into
the atmosphere.
Most environmentally related taxes with implications for greenhouse gas
emissions in OECD countries are levied on energy products and motor
vehicles, rather than on CO2 emissions directly.
As such, non-transport sectors as the agricultural sector which
produces large amounts of methane are typically left untaxed by current
policies. Also, revenue of the emissions taxes are not always used to offset the emissions directly.
Emission taxes can be both cost-effective and environmentally effective.
Difficulties with emission taxes include their potential unpopularity,
and the fact that they cannot guarantee a particular level of emissions
reduction. Emissions or energy taxes also often fall disproportionately on lower income classes.
In developing countries, institutions may be insufficiently developed
for the collection of emissions fees from a wide variety of sources.
Investment
Another indirect method of encouraging uses of renewable energy, and
pursue sustainability and environmental protection, is that of prompting
investment in this area through legal means, something that is already
being done at national level as well as in the field of international
investment.
Although state policies tackling climate change are seen as a
threat to investors, so is global warming itself. As well as a policy
risk, Ernst and Young identify physical, secondary, liability, transitional and reputation-based risks.
Therefore, it is increasingly seen to be in the interest of investors
to accept climate change as a real threat which they must proactively
and independently address.
Carbon emissions trading
With the creation of a market for trading carbon dioxide emissions
within the Kyoto Protocol, it is likely that London financial markets
will be the centre for this potentially highly lucrative business; the New York and Chicago stock markets may have a lower trade volume than expected as long as the US maintains its rejection of the Kyoto.
However, emissions trading may delay the phase-out of fossil fuels.
In the north-east United States, a successful cap and trade program has shown potential for this solution.
The European Union Emission Trading Scheme (EU ETS)
is the largest multi-national, greenhouse gas emissions trading scheme
in the world. It commenced operation on 1 January 2005, and all 28
member states of the European Union
participate in the scheme which has created a new market in carbon
dioxide allowances estimated at 35 billion Euros (US$43 billion) per
year. The Chicago Climate Exchange was the first (voluntary) emissions market, and is soon to be followed by Asia's first market (Asia Carbon Exchange).
A total of 107 million metric tonnes of carbon dioxide equivalent have
been exchanged through projects in 2004, a 38% increase relative to 2003
(78 Mt CO2e).
Twenty three multinational corporations have come together in the G8 Climate Change Roundtable, a business group formed at the January 2005 World Economic Forum. The group includes Ford, Toyota, British Airways, and BP. On 9 June 2005 the Group published a statement
stating that there was a need to act on climate change and claiming
that market-based solutions can help. It called on governments to
establish "clear, transparent, and consistent price signals" through
"creation of a long-term policy framework" that would include all major
producers of greenhouse gases.
The Regional Greenhouse Gas Initiative is a proposed carbon trading scheme being created by nine North-eastern and Mid-Atlantic American states; Connecticut, Delaware, Maine, Massachusetts, New Hampshire, New Jersey, New York, Rhode Island, and Vermont. The scheme was due to be developed by April 2005 but has not yet been completed.
Implementation
Since 2000, rising CO
2 emissions in China and the rest of world have eclipsed the output of the United States and Europe.
Per person, the United States generates carbon dioxide at a far faster rate than other primary regions.
Implementation puts into effect climate change mitigation strategies
and targets. These can be targets set by international bodies or
voluntary action by individuals or institutions. This is the most
important, expensive and least appealing aspect of environmental
governance.
Funding
e Fund,
is often provided by nations, groups of nations and increasingly NGO
and private sources. These funds are often channelled through the Global
Environmental Facility (GEF). This is an environmental funding
mechanism in the World Bank which is designed to deal with global
environmental issues.
The GEF was originally designed to tackle four main areas: biological
diversity, climate change, international waters and ozone layer
depletion, to which
land degradation and
persistent organic pollutant
were added. The GEF funds projects that are agreed to achieve global
environmental benefits that are endorsed by governments and screened by
one of the GEF's implementing agencies.
Research
It
has been estimated that only 0.12% of all funding for climate-related
research is spent on the social science of climate change mitigation.
Vastly more funding is spent on natural science studies of climate
change and considerable sums are also spent on studies of impact of and
adaptation to climate change.
It has been argued that this is a misallocation of resources, as the
most urgent puzzle at the current juncture is to work out how to change
human behavior to mitigate climate change, whereas the natural science
of climate change is already well established and there will be decades
and centuries to handle adaptation.
Problems
There are numerous issues which result in a current perceived lack of implementation.
It has been suggested that the main barriers to implementation are
Uncertainty, Fragmentation, Institutional void, Short time horizon of
policies and politicians and Missing motives and willingness to start
adapting. The relationships between many climatic processes can cause
large levels of uncertainty as they are not fully understood and can be a
barrier to implementation. When information on climate change is held
between the large numbers of actors involved it can be highly dispersed,
context specific or difficult to access causing fragmentation to be a
barrier. Institutional void is the lack of commonly accepted rules and
norms for policy processes to take place, calling into question the
legitimacy and efficacy of policy processes. The Short time horizon of
policies and politicians often means that climate change policies are
not implemented in favour of socially favoured societal issues.
Statements are often posed to keep the illusion of political action to
prevent or postpone decisions being made. Missing motives and
willingness to start adapting is a large barrier as it prevents any
implementation. The issues that arise with a system which involves international government cooperation, such as cap and trade,
could potentially be improved with a polycentric approach where the
rules are enforced by many small sections of authority as opposed to one
overall enforcement agency. Concerns about metal requirement and/or availability for essential decarbonization technologies such as photovoltaics, nuclear power, and (plug-in hybrid) electric vehicles have also been expressed as obstacles.
Occurrence
Despite a perceived lack of occurrence,
evidence of implementation is emerging internationally. Some examples
of this are the initiation of NAPA's and of joint implementation. Many
developing nations have made National Adaptation Programs of Action
(NAPAs) which are frameworks to prioritize adaption needs. The implementation of many of these is supported by GEF agencies. Many developed countries are implementing 'first generation' institutional adaption plans particularly at the state and local government scale.
There has also been a push towards joint implementation between
countries by the UNFCCC as this has been suggested as a cost-effective
way for objectives to be achieved.
Montreal protocol
Although not designed for this purpose, the Montreal Protocol has benefited climate change mitigation efforts. The Montreal Protocol is an international treaty that has successfully reduced emissions of ozone-depleting substances (for example, CFCs), which are also greenhouse gases.
Territorial policies
Many countries are aiming for net zero emissions, and many have either carbon taxes or carbon emission trading.
Emission trading and carbon taxes around the world (2019)
United States
Efforts to reduce greenhouse gas emissions by the United States include energy policies which encourage efficiency through programs like Energy Star, Commercial Building Integration, and the Industrial Technologies Program.
In the absence of substantial federal action, state governments have adopted emissions-control laws such as the Regional Greenhouse Gas Initiative in the Northeast and the Global Warming Solutions Act of 2006 in California.
In 2019 a new climate change bill was introduced in Minnesota. One of
the targets, is making all the energy of the state carbon free, by 2030.
China
As to 2019, China implements more than 100 policies to fight climate change. China said in the Paris Agreement
that its emission will begin to fall by 2030, but it will possibly
occur by 2026. This can position China as a leader on the issue because
it is the biggest emitter of GHG emissions, so if it really reduces them, the significance will be large.
European Union
The climate commitments of the European Union
are divided into 3 main categories: targets for the year 2020, 2030 and
2050. The European Union claim that their policies are in line with the
goal of the Paris Agreement.
Targets for the year 2020:
- Reduce GHG emissions by 20% from the level in 1990.
- Produce 20% of energy from renewable sources.
- Increase Energy Efficiency by 20%.
Targets for the year 2030:
- Reduce GHG emission by 40% from the level of 1990. In 2019 The
European Parliament adopted a resolution upgrading the target to 55%
- Produce 32% of energy from renewables.
- Increase energy efficiency by 32.5%.
Targets for the year 2050:
Implementation:
The European Union claims that he has already achieved the 2020
target for emission reduction and have the legislation needed to achieve
the 2030 targets. Already in 2018, its GHG emissions were 23% lower
that in 1990.
New Zealand
New Zealand made significant pledges on climate change mitigation in
the year 2019: reduce emissions to zero by 2050, plant 1 billion trees
by 2028, and encouraging farmers to reduce emissions by 2025 or face
higher taxes Already in 2019 New Zealand banned new offshore oil and gas
drilling and decided the climate change issues will be examined before
every important decision.
In early December 2020, Prime Minister Jacinda Ardern
declared a climate change emergency and pledged that the New Zealand
Government would be carbon neutral by 2025. Key goals and initiatives
include requiring the public sector to buy only electric or hybrid
vehicles, government buildings will have to meet new "green" building
standards, and all 200 coal-fired boilers in public service buildings
will be phased out.
Nigeria
To mitigate the adverse effect of climate change, not only did
Nigeria sign the Paris agreement to reduce emission, in its national
climate pledge, the Nigerian government has promised to “work towards”
ending gas flaring by 2030. In order to achieve this goal, the
government established a Gas Flare Commercialisation Programme to
encourage investment in practices that reduce gas flaring. Also, the
federal government has approved a new National Forest Policy which is
aimed at “protecting ecosystems” while enhancing social development.
Effort is also been made to stimulate the adoption of climate-smart
agriculture and the planting of trees.
Developing countries
In order to reconcile economic development with mitigating carbon emissions, developing countries need particular support, both financial and technical. One of the means of achieving this is the Kyoto Protocol's Clean Development Mechanism (CDM). The World Bank's Prototype Carbon Fund is a public private partnership that operates within the CDM.
An important point of contention, however, is how overseas development assistance not directly related to climate change mitigation is affected by funds provided to climate change mitigation. One of the outcomes of the UNFCC Copenhagen Climate Conference was the Copenhagen Accord, in which developed countries promised to provide US$30 million between 2010 and 2012 of new and additional resources. Yet it remains unclear what exactly the definition of additional is and the European Commission has requested its member states to define what they understand to be additional, and researchers at the Overseas Development Institute have found four main understandings:
- Climate finance classified as aid, but additional to (over and above) the '0.7%' ODA target;
- Increase on previous year's Official Development Assistance (ODA) spent on climate change mitigation;
- Rising ODA levels that include climate change finance but where it is limited to a specified percentage; and
- Increase in climate finance not connected to ODA.
The main point being that there is a conflict between the OECD
states budget deficit cuts, the need to help developing countries adapt
to develop sustainably and the need to ensure that funding does not
come from cutting aid to other important Millennium Development Goals.
However, none of these initiatives suggest a quantitative cap on
the emissions from developing countries. This is considered as a
particularly difficult policy proposal as the economic growth of
developing countries are proportionally reflected in the growth of
greenhouse emissions. Critics
of mitigation often argue that, the developing countries' drive to
attain a comparable living standard to the developed countries would
doom the attempt at mitigation of global warming. Critics
also argue that holding down emissions would shift the human cost of
global warming from a general one to one that was borne most heavily by
the poorest populations on the planet.
In an attempt to provide more opportunities for developing countries to adapt clean technologies, UNEP and WTO urged the international community to reduce trade barriers and to conclude the Doha trade round "which includes opening trade in environmental goods and services".
In 2019 week of climate action in Latin America and the Caribbean
result in a declaration in which leaders says that they will act to
reduce emissions in the sectors of transportation, energy, urbanism,
industry, forest conservation and land use and "sent a message of
solidarity with all the people of Brazil suffering the consequences of
the rainforest fires in the Amazon region,
underscoring that protecting the world's forests is a collective
responsibility, that forests are vital for life and that they are a
critical part of the solution to climate change".
Non-governmental approaches
While
many of the proposed methods of mitigating global warming require
governmental funding, legislation and regulatory action, individuals and
businesses can also play a part in the mitigation effort.
Choices in personal actions and business operations
Environmental groups encourage individual action against global warming, often aimed at the consumer. Common recommendations include lowering home heating and cooling usage, burning less gasoline, supporting renewable energy sources, buying local products to reduce transportation, turning off unused devices, and various others.
A geophysicist at Utrecht University
has urged similar institutions to hold the vanguard in voluntary
mitigation, suggesting the use of communications technologies such as videoconferencing to reduce their dependence on long-haul flights.
Air travel and shipment
In 2008, climate scientist Kevin Anderson raised concern about the growing effect of rapidly increasing global air transport on the climate in a paper, and a presentation,
suggesting that reversing this trend is necessary to reduce
emissions.Air travel is having complex impacts on climate due to the
wide range of emissions on varying attitudes within a different time
span
Part of the difficulty is that when aviation emissions
are made at high altitude, the climate impacts are much greater than
otherwise. Others have been raising the related concerns of the
increasing hypermobility
of individuals, whether traveling for business or pleasure, involving
frequent and often long-distance air travel, as well as air shipment of
goods.
Business opportunities and risks
Investor response
Climate change is also a concern for large institutional investors
who have a long term time horizon and potentially large exposure to the
negative impacts of global warming because of the large geographic
footprint of their multi-national holdings. Socially responsible investing
funds allow investors to invest in funds that meet high ESG
(environmental, social, governance) standards as such funds invest in
companies that are aligned with these goals. Proxy firms can be used to draft guidelines for investment managers that take these concerns into account.
Legal action
In some countries, those affected by climate change may be able to
sue major producers. Attempts at litigation have been initiated by
entire peoples such as Palau and the Inuit, as well as non-governmental organizations such as the Sierra Club. Although proving that particular weather events are due specifically to global warming may never be possible, methodologies have been developed to show the increased risk of such events caused by global warming.
For a legal action for negligence
(or similar) to succeed, "Plaintiffs ... must show that, more probably
than not, their individual injuries were caused by the risk factor in
question, as opposed to any other cause. This has sometimes been
translated to a requirement of a relative risk of at least two." Another route (though with little legal bite) is the World Heritage Convention, if it can be shown that climate change is affecting World Heritage Sites like Mount Everest.
Besides countries suing one another, there are also cases where
people in a country have taken legal steps against their own government.
Legal action for instance has been taken to try to force the US Environmental Protection Agency to regulate greenhouse gas emissions under the Clean Air Act, and against the Export-Import Bank and OPIC for failing to assess environmental impacts (including global warming impacts) under NEPA.
In the Netherlands and Belgium, organisations such as the foundation Urgenda and the vzw Klimaatzaak in Belgium
have also sued their governments as they believe their governments
aren't meeting the emission reductions they agreed to. Urgenda have
already won their case against the Dutch government.
According to a 2004 study commissioned by Friends of the Earth, ExxonMobil,
and its predecessors caused 4.7 to 5.3 percent of the world's man-made
carbon dioxide emissions between 1882 and 2002. The group suggested that
such studies could form the basis for eventual legal action.
In 2015, Exxon received a subpoena. According to the Washington Post and confirmed by the company, the attorney general of New York, Eric Schneiderman,
opened an investigation into the possibility that the company had
misled the public and investors about the risks of climate change. In October 2019, the trial began. Massachusetts sued Exxon also, for hiding the impact of climate change.
In 2019, 22 states, six cities and Washington DC in United States, sued the Trump administration for repealing the Clean Power Plan.
In 2020 a group of swiss senior women sued their government for
too week action on stopping climate change. They claimed that the
increase in heat waves caused by climate change, particulary impact the
elderly people.
In November 2020 the European Court of Human Rights
ordered to 33 countries to respond to the climate lawsuit from 4
children and 2 adults living in Portugal. The lawsuit will be treated as
a priority by the court.
Activism
Environmental organizations organize different actions such as Peoples Climate Marches and Divestment from fossil fuels. 1,000 organizations with a worth of 8 trillion dollars, made commitments to divest from fossil fuel to 2018. Another form of action is climate strike. In January 2019 12,500 students marched in Brussels demanding Climate action. In 2019 The organization Extinction Rebellion
organized massive protests demanding "tell the truth about climate
change, reduce carbon emissions to zero by 2025, and create a citizens'
assembly to oversee progress", including blocking roads. Many were
arrested. In many cases, activism brings positive results.
A major event was the global climate strike in September 2019 organized by Fridays For Future and Earth Strike. The target was to influence the climate action summit organized by the UN on September 23. According to the organizers four million people participated in the strike on September 20.
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