https://en.wikipedia.org/wiki/Family_values Family values, sometimes referred to as familial values, are traditional or cultural values that pertain to the family's
structure, function, roles, beliefs, attitudes, and ideals.
Additionally, the concept of family values may be understood as a
reflection of the degree to which familial relationships are valued
within an individual's life.
In the social sciences and U.S. political discourse, the conventional term traditional family describes the nuclear family—a child-rearing environment composed of a leading father, a homemaking mother, and their nominally biological children. A family deviating from this model is considered a nontraditional family.
Definition
Several online dictionaries define "family values" as the following:
"the moral and ethical principles traditionally upheld and passed on within a family, as fidelity, honesty, truth, and faith."
"values especially of a traditional or conservative kind which are held to promote the sound functioning of the family and to strengthen the fabric of society."
"values held to be traditionally taught or reinforced within a family, such as those of high moral standards and discipline."
Familialism or familism is the ideology that puts priority on family and family values. Familialism advocates for a welfare system where families, rather than the government, take responsibility for the care of their members.
In the United States, the banner of "family values" has been used by socialconservatives to express opposition to abortion, pornography, non-abstinence sex education, divorce, LGBTQ validity, same-sex marriage, gender ideology, secularism, and atheism. American conservative groups have made successful inroads promoting these policies in Africa since the early 2000s, describing them as African family values.
The phrase family values originated with the 1992 Republican National Convention, for their "Family Values Night", featuring Barbara Bush
as the keynote speaker. In the short term the phrase was widely panned,
and at the time the staying power of the idea was underestimated.
Interpretations of Islamic learnings and Arab culture are common for the majority of Saudis. Islam is a driving cultural force that dictates a submission to the will of Allah.
The academic literature suggests that the family is regarded as the
main foundation of Muslim society and culture; the family structure and
nature of the relationship between family members are influenced by the
Islamic religion. Marriage in Saudi culture means the union of two families, not just two individuals. In Muslim society, marriage involves a social contract that occurs with the consent of parents or guardians. Furthermore, marriage is considered the only legitimate outlet for sexual desires, and sex outside marriage (zina) is a crime that is punished under Islamic law.
The Saudi family includes extended families, as the extended family provides the individual with a sense of identity. The father is often the breadwinner and protector of the family, whereas the mother is often the homemaker and the primary caretaker of the children. Parents are regarded with high respect, and children are strongly encouraged to respect and obey their parents. Often, families provide care for elders. Until recently, because families and friends are expected to provide elderly care, nursing homes were considered culturally unacceptable.
In sociological terms, nontraditional families make up the majority of American households. As of 2014, only 46% of children in the U.S. live in a traditional family, down from 61% in 1980.
This number includes only families with parents who are in their first
marriage, whereas the percentage of children simply living with two
married parents is 65% as of 2016.
Organizations
These groups are associated with "family values". Many of them are also listed as hate groups by the Southern Poverty Law Center as a result of their anti-LGBT activism.
Adrenal insufficiency is a condition in which the adrenal glands do not produce adequate amounts of steroid hormones. The adrenal glands—also referred to as the adrenal cortex—normally secrete glucocorticoids (primarily cortisol), mineralocorticoids (primarily aldosterone), and androgens. These hormones are important in regulating blood pressure, electrolytes, and metabolism as a whole.Deficiency of these hormones leads to symptoms ranging from abdominal pain, vomiting, muscle weakness and fatigue, low blood pressure, depression, mood and personality changes (in mild cases) to organ failure and shock (in severe cases). Adrenal crisis
may occur if a person having adrenal insufficiency experiences
stresses, such as an accident, injury, surgery, or severe infection;
this is a life-threatening medical condition resulting from severe
deficiency of cortisol in the body. Death may quickly follow.
Adrenal insufficiency can be caused by dysfunction of the adrenal gland itself, whether by destruction (e.g. Addison's disease), failure of development (e.g. adrenal dysgenesis), or enzyme deficiency (e.g. congenital adrenal hyperplasia). Adrenal insufficiency can also occur when the pituitary gland or the hypothalamus do not produce adequate amounts of the hormones that assist in regulating adrenal function. This is called secondary adrenal insufficiency (when caused by lack of production of adrenocorticotropic hormone (ACTH) in the pituitary gland) or tertiary adrenal insufficiency (when caused by lack of corticotropin-releasing hormone (CRH) in the hypothalamus).
Types
There are three major types of adrenal insufficiency, depending on the affected organ.
Primary adrenal insufficiency is due to impairment of the adrenal glands, resulting in a lack of glucocorticoid production. Since the adrenal glands are directly affected, mineralocorticoid production is also reduced. Principal causes include:
Autoimmune: e.g. Addison's disease (also called autoimmune adrenalitis), which has been identified to be the cause of 80–90% of primary adrenal insufficiency cases since 1950.
Acquired: Bilateral Adrenalectomy to treat recurrent Cushing's Disease/Syndrome
Secondary adrenal insufficiency is caused by impairment of the pituitary gland, resulting in a lack of adrenocorticotropic hormone
(ACTH) production and subsequent decreased adrenal stimulation. Since
the adrenal glands are not directly affected, the effect on
mineralocorticoid production is minimal, as ACTH primarily affects
glucocorticoid production. Principal causes include:
Pituitary adenoma or craniopharyngioma: Tumors in the pituitary gland can suppress production of adrenocorticotropic hormone (ACTH). High-dose irradiation (>30 Gy) to the hypothalamus or the pituitary gland can cause ACTH deficiency.
Surgery or radiation: Pituitary gland surgery and/or radiation can lead to destruction of ACTH-producing tissue.
Exogenouscorticosteroid
use: Exogenous corticosteroids suppress the stimulation of the
hypothalamus and the pituitary gland to secrete CRH and ACTH,
respectively. These cases may present with symptoms of cortisol excess (see Cushing's syndrome).
Sheehan's syndrome: Loss of blood flow to the pituitary gland following childbirth
Pituitary apoplexy: Bleeding or impaired blood supply to the pituitary gland
Tertiary adrenal insufficiency is caused by impairment of the hypothalamus, resulting in a lack of corticotropin-releasing hormone (CRH) production, causing downstream reduction in ACTH production and subsequently decreasing adrenal stimulation.
Since the adrenal glands are not directly affected, the effect on
mineralocorticoid production is minimal, as ACTH primarily affects
glucocorticoid production. Principal causes include:
Sudden withdrawal from long-term exogenous steroid use
Diagram
detailing the hypothalamus–pituitary–adrenal axis in the normal state,
primary adrenal insufficiency, secondary adrenal insufficiency, and
tertiary adrenal insufficiency The adrenal cortex produces different hormones in different areas of the organs, called zonas.
When functioning normally, the adrenal glands secrete glucocorticoids (primarily, cortisol) in the zona fasciculata and mineralocorticoids (primarily, aldosterone) in the zona glomerulosa to regulate metabolism, blood pressure, and electrolyte balance. Adrenal hormone production is controlled by the hypothalamic–pituitary–adrenal axis, in which the hypothalamus produces corticotropin-releasing hormone (CRH), which stimulates the pituitary gland to produce adrenocorticotropic hormone (ACTH), which stimulates the adrenal gland to produce cortisol. High levels of cortisol inhibit the production of both CRH and ACTH, forming a negative feedback loop.
The types of adrenal insufficiency thus refer to the level of the axis
in which the dysfunction originates: primary, secondary, and tertiary
for adrenal glands, pituitary gland, and hypothalamus, respectively.
In adrenal insufficiency, there is a deficiency in cortisol
production which may be accompanied by a deficiency in aldosterone
production (predominantly in primary adrenal insufficiency).
Depending on the cause and type of adrenal insufficiency, the mechanism
of the disease differs. Generally, the symptoms manifest through the
systemic effects of cortisol and aldosterone. In secondary and tertiary adrenal insufficiency, there is no effect on the production of aldosterone within the zona glomerulosa as this process is regulated by the renin–angiotensin–aldosterone system (RAAS), not ACTH.
Adrenal insufficiency can also affect the zona reticularis and disrupt production of androgens, which are precursors to testosterone and estrogen. This leads to a deficiency of sex hormones and can contribute to symptoms of depression and menstrual irregularities.
Cortisol deficiency
Cortisol increases blood sugar by inducing gluconeogenesis (glucose production) in the liver, lipolysis (fat breakdown) in adipose tissue, and proteolysis (muscle breakdown) in muscle while increasing glucagon secretion and decreasing insulin secretion in the pancreas. Overall, these actions cause the body to use fat stores and muscle for energy. Deficiency results in hypoglycemia, with associated nausea, vomiting, fatigue, and weakness.
In primary adrenal insufficiency, the lack of negative feedback from cortisol leads to increased production of CRH and ACTH. ACTH is derived from pro-opiomelanocortin (POMC), which is cleaved into ACTH as well as α-MSH, which regulates production of melanin in the skin. The overproduction of α-MSH leads to the characteristic hyperpigmentation of Addison's disease.
Aldosterone deficiency
Although
the production of aldosterone occurs within the adrenal cortex, it is
not induced by adrenocorticotropic (ACTH); instead, it is regulated by
the renin–angiotensin–aldosterone system (RAAS). Renin production in the juxtaglomerular cells of the kidney is induced by decreased arterial blood pressure, decreased sodium content in the distal convoluted tubule, and increased sympathetic tone. Renin initiates the downstream sequence of cleavage of angiotensinogen to angiotensin I to angiotensin II, in which angiotensin II stimulates aldosterone production in the zona glomerulosa. Thus, dysfunction of the pituitary gland or the hypothalamus does not affect the production of aldosterone. However, in primary adrenal insufficiency, damage to the adrenal cortex (e.g. autoimmune adrenalitis a.k.a. Addison's disease) can lead to destruction of the zona glomerulosa and therefore a loss of aldosterone production.
Aldosterone acts on mineralocorticoid receptors on epithelial cells lining the distal convoluted tubule, activating epithelial sodium channels (ENaC) and the Na⁺/K⁺-ATPase pump. This results in the absorption of sodium (with resulting retention of fluid) and the excretion of potassium. Deficiency of aldosterone leads to urinary loss of sodium and effective circulating volume, as well as retention of potassium. This can cause hypotension (in severe cases, shock), dizziness (from orthostatic hypotension), dehydration, and salt craving.
Differently from mineralocorticoid deficiency, glucocorticoid deficiency does not cause a negative sodium balance (in fact a positive sodium balance may occur).
Causes of adrenal insufficiency can be categorized by the
mechanism through which they cause the adrenal glands to produce
insufficient cortisol. These are adrenal destruction (disease processes leading to glandular damage), impaired steroidogenesis (the gland is present but is biochemically unable to produce cortisol), or adrenal dysgenesis (the gland has not formed adequately during development).
Adrenal insufficiency can also result when a patient has a brain mass in the pituitary gland (e.g. pituitary adenoma, craniopharyngioma)
which can take up space and interfere with the secretion of pituitary
hormones such as ACTH, therefore leading to decreased adrenal
stimulation (secondary adrenal insufficiency). The same can occur with masses in the hypothalamus (tertiary adrenal insufficiency).
Corticosteroid withdrawal
Use of high-dose steroids for more than a week begins to produce suppression of the person's adrenal glands because the exogenous glucocorticoids
suppress release of hypothalamic corticotropin-releasing hormone (CRH)
and pituitary adrenocorticotropic hormone (ACTH). With prolonged
suppression, the adrenal glands atrophy (physically shrink), and can
take months to recover full function after discontinuation of the
exogenous glucocorticoid. During this recovery time, the person is
vulnerable to adrenal insufficiency during times of stress, such as
illness, due to both adrenal atrophy and suppression of CRH and ACTH
release. Use of steroids joint injections may also result in adrenal suppression after discontinuation.
Adrenal dysgenesis
All causes in this category are genetic, and generally very rare. These include mutations to the SF1transcription factor, congenital adrenal hypoplasia due to DAX-1 gene mutations and mutations to the ACTH receptor gene (or related genes, such as in the Triple A or Allgrove syndrome). DAX-1 mutations may cluster in a syndrome with glycerol kinase deficiency with a number of other symptoms when DAX-1 is deleted together with a number of other genes.
Diagnosis
The first step of diagnosing adrenal insufficiency is confirming inappropriately low cortisol secretion.
This is followed by determining the origin of dysfunction (adrenal
glands, pituitary gland, or hypothalamus) and therefore the type of
adrenal insufficiency (primary, secondary, or tertiary). After narrowing down the source, further testing can elucidate the cause of insufficiency.
If a patient is suspected to be experiencing an acute adrenal
crisis, immediate treatment with IV corticosteroids is imperative and
should not be delayed for any testing, as the patient's health can
deteriorate rapidly and result in death without replacing the
corticosteroids.
Dexamethasone should be used as the corticosteroid of choice in these
cases as it is the only corticosteroid that will not affect diagnostic
test results.
To confirm inappropriately low cortisol secretion, testing can
include baseline morning cortisol level in the blood or morning cortisol
level in the saliva. Cortisol levels typically peak in the morning; thus, low values indicate true adrenal insufficiency. Urinary free cortisol can also be measured, but are not necessary for diagnosis.
To determine the origin of dysfunction, the ACTH stimulation test is the best initial test as it can differentiate between primary and secondary adrenal insufficiency. If cortisol levels remain low following ACTH stimulation, then the diagnosis is primary adrenal insufficiency.
If cortisol levels increase following ACTH stimulation, then the
diagnosis is either secondary or tertiary adrenal insufficiency. The corticotropin-releasing hormone test can then differentiate between secondary and tertiary adrenal insufficiency. Additional testing can include basal plasma ACTH, renin, and aldosterone concentrations, as well as a blood chemistry panel to check for electrolyte imbalances.
Depending on the type of adrenal insufficiency, there are many
possible causes and therefore many different avenues of testing (see Causes above). For primary adrenal insufficiency, the most common cause is autoimmune adrenalitis (Addison's disease); therefore, 21-hydroxylase autoantibodies should be checked. Structural abnormalities of the adrenal glands can be detected on CT imaging. For secondary and tertiary adrenal insufficiency, an MRI of the brain can be obtained to detect structural abnormalities such as masses, metastasis, hemorrhage, infarction, or infection.
Automatically includes diagnosis of secondary (hypopituitarism)
2
Only if CRH production in the hypothalamus is intact
3
Value doubles or more in stimulation
4
Value less than doubles in stimulation
5
Most common, does not include all possible causes
6
Usually because of very large tumor (macroadenoma)
7
Includes Addison's disease
Treatment
In
general, the treatment of adrenal insufficiency requires replacement of
deficient hormones, as well as treatment of any underlying cause. All types of adrenal insufficiency will require glucocorticoid repletion. Many cases (typically, primary adrenal insufficiency) will also require mineralocorticoid repletion.
In rarer cases, repletion of androgens may also be indicated, typically
in female patients with mood disturbances and changes in well-being.
Adrenal crisis (acute) treatment
Intravenous fluids
Intravenous glucocorticoids
typically hydrocortisone (Cortef) but dexamethasone (Decadron) may be used if diagnostic studies are necessary, as dexamethasone does not affect testing results
Supportive measures and correction of any additional issues such as electrolyte abnormalities
Primary
adrenal insufficiency predisposes to higher risk of death, mostly due
to infection, cardiovascular disease, and adrenal crisis. Delayed diagnosis can impair quality of life, and lack of treatment brings high mortality. However, with proper diagnosis, monitoring, and treatment, people with adrenal insufficiency can live normally.
https://en.wikipedia.org/wiki/Emotional_dysregulation Emotional dysregulation is characterized by an inability to flexibly respond to and manage emotional states, resulting in intense and prolonged emotional reactions that deviate from social norms,
given the nature of the environmental stimuli encountered. Such
reactions not only deviate from accepted social norms but also surpass
what is informally deemed appropriate or proportional to the encountered
stimuli.
Possible manifestations of emotion dysregulation include extreme tearfulness, angry outbursts or behavioral outbursts such as destroying or throwing objects, aggression towards self or others, and threats to kill oneself.
Emotion dysregulation can lead to behavioral problems and can
interfere with a person's social interactions and relationships at home,
in school, or at their place of employment.
Etymology
The word dysregulation is a neologism created by combining the prefix dys- to regulation. According to Webster's Dictionary, dys- has various roots and is of Greek origin. With Latin and Greek roots, it is akin to Old Englishtō-, te- 'apart' and Sanskritdus- 'bad, difficult'. It is frequently confused with the spelling disregulation, with the prefix dis meaning 'the opposite of' or 'absence of'; while disregulation refers to the removal or absence of regulation, dysregulation refers to ways of regulating that are inappropriate or ineffective.
Child psychopathology
There are links between child emotional dysregulation and later psychopathology. For instance, ADHD symptoms are associated with problems with emotional regulation, motivation, and arousal.
One study found a connection between emotional dysregulation at 5 and
10 months, and parent-reported problems with anger and distress at 18
months. Low levels of emotional regulation behaviors at 5 months were also related to non-compliant behaviors at 30 months.
While links have been found between emotional dysregulation and child
psychopathology, the mechanisms behind how early emotional dysregulation
and later psychopathology are related are not yet clear.
Symptoms
Smoking, self-harm, eating disorders, and addiction have all been associated with emotional dysregulation. Somatoform disorders may be caused by a decreased ability to regulate and experience emotions or an inability to express emotions in a positive way.
Individuals who have difficulty regulating emotions are at risk for
eating disorders and substance abuse as they use food or substances as a
way to regulate their emotions. Emotional dysregulation is also found in people who have an increased risk of developing a mental disorder, particularly an affective disorder such as depression or bipolar disorder.
Childhood
Dysregulation is more prevalent in this age group, and is generally seen to decrease as children develop.
During early childhood, emotional dysregulation or reactivity is
considered to be situational rather than indicative of emotional
disorders.
It is important to consider parental mood disorders as genetic and
environmental determinants. Children of parents with symptoms of
depression are less likely to learn strategies for regulating their
emotions and are at risk of inheriting a mood disorder. When parents have difficulty with regulating their emotions, they often cannot teach their children to regulate properly. The role of parents in a child's development is acknowledged by attachment theory,
which argues that the characteristics of the caregiver-child
relationship impact future relationships. Current research indicates
that parent-child relationships characterized by less affection and
greater hostility may result in children developing emotional regulation
problems.
If the child's emotional needs are ignored or rejected, they may
experience greater difficulty dealing with emotions in the future. Moreover, conflict between parents is linked to increased emotional reactivity or dysregulation in children.
Other factors involved include the quality of relationship with peers,
the child's temperament, and social or cognitive understanding. Additionally, loss or grief can contribute to emotional dysregulation.
Research has shown that failures in emotional regulation may be related to the display of acting out, externalizing disorders,
or behavior problems. When presented with challenging tasks, children
who were found to have defects in emotional regulation (high-risk) spent
less time attending to tasks and more time throwing tantrums or
fretting than children without emotional regulation problems (low-risk).
High-risk children had difficulty with self-regulation and had
difficulty complying with requests from caregivers and were more
defiant. Emotional dysregulation has also been associated with childhood social withdrawal.
Internalizing behaviors
Emotional dysregulation in children can be associated with internalizing behaviors including:
Attachment theory and the idea of an insecure attachment is
implicated in emotional dysregulation. Greater attachment security
correlates with less emotional dysregulation in daughters. Moreover, it has been observed that more female teens struggle with emotional dysregulation than males. Professional treatment, such as therapy or admittance into a psychiatric facility, is recommended.
Adulthood
Emotional
dysregulation tends to present as emotional responses that may seem
excessive compared to the situation. Individuals with emotional
dysregulation may have difficulty calming down, avoid difficult
feelings, or focus on the negative. On average, women tend to score higher on scales of emotional reactivity than men.
A study at University College in Ireland found that dysregulation
correlates to negative feelings about one's ability to cope with
emotions and rumination in adults. They also found dysregulation to be
common in a sample of individuals not affected by mental disorders.
Part of emotional dysregulation, which is a core characteristic in borderline personality disorder, is affective instability, which manifests as rapid and frequent shifts in mood of high affect intensity and rapid onset of emotions,
often triggered by environmental stimuli. The return to a stable
emotional state is notably delayed, exacerbating the challenge of
achieving emotional equilibrium. This instability is further intensified
by an acute sensitivity to psychosocial cues, leading to significant challenges in managing emotions effectively.
Impact on relationships
Established relationships
Relationships
are generally linked to better well-being, but dissatisfaction in
relationships can lead to increased divorce, worsened health, and
potential violence.
Emotional dysregulation plays a role in relationship quality and
overall satisfaction. It can be difficult for emotionally dysregulated
individuals to maintain healthy relationships.
People who struggle with emotional dysregulation often externalize,
internalize, or dissociate when exposed to stressors. These behaviors
are attempts to regulate emotions but often are ineffective in
addressing stress in relationships.
This commonly presents itself as intense anxiety around relationships,
poor ability to set and sustain boundaries, frequent and damaging
arguments, preoccupation with loneliness, worries about losing a
relationship, and jealous or idealizing feelings towards others. These feelings may be accompanied by support-seeking behaviors such as clinging, smothering, or seeking to control.
The counterpart of emotional dysregulation, emotional regulation, strengthens relationships. The ability to regulate negative emotions in particular is linked to positive coping and thus higher relationship satisfaction.
Emotional regulation and communication skills are linked to secure
attachment, which has been related to higher partner support as well as
openness in discussing negative experiences and resolving conflict.
On the other hand, emotional dysregulation has a negative impact on
relationships. Multiple studies note the effects of emotion
dysregulation on relationship quality. One study found that relationship
satisfaction is lower in couples that lack impulse control or
regulatory strategies.
Another study found that both husbands' and wives' emotional reactivity
was negatively linked with marriage quality as well as perceptions of
partner responsiveness.
The literature concludes that dysregulation increases instances of
perceived criticism, contributes to physical and psychological violence,
and worsens depression, anxiety, and sexual difficulties. Dysregulation has also been observed to lower empathy and decrease relationship satisfaction, quality, and intimacy.
Sexual health
Research
conflicts on whether higher levels of emotional reactivity are linked
to increases or decreases in sexual desire. Moreover, this effect could
differ between men and women based on observed differences in emotional
reactivity between genders. Some research posits that higher emotional reactivity in women is linked to greater sexual attraction in their male partners.
However, difficulties in regulating emotions have been linked to
poorer sexual health, both in regards to ability and overall
satisfaction.
Emotional dysregulation plays a role in nonconsensual and violent
sexual encounters. Emotional regulation skills prevent verbal coercion
by regulating feelings of sexual attraction in men.
Consequently, a lack of emotional regulation skills can cause both
internalizing and externalizing behaviors in a sexual context. This may
mean violence, which can serve as a strategy for regulating emotion.
In a non-violent context, insecurely attached individuals may seek to
satisfy their need for connection or to resolve relational issues with
sex.
Communication can also be hindered, as emotional dysregulation has
been linked to an inability to express oneself in sexual situations. This can lead to victimization as well as further sexual difficulties. Thus, the ability to both recognize emotions and express negative emotions are important for communication and social adjustment, including within sexual contexts.
Mediating effects
While
personal characteristics and experiences can contribute to
externalizing and internalizing behaviors as listed above, emotional
regulation has an interpersonal aspect. Couples who effectively
co-regulate have higher emotional satisfaction and stability. Openly discussing emotions in the relationship can help to validate feelings of insecurity and encourage closeness.
For partners who struggle with emotional dysregulation, there are
available treatments. Couple's therapy has shown itself to be an
effective method of improving relationship satisfaction and quality by
positively impacting the process of emotional regulation in
relationships.
Protective factors
Early
experiences with caregivers can lead to differences in emotional
regulation. The responsiveness of a caregiver to an infant's signals can
help an infant regulate their emotional systems. Caregiver interaction
styles that overwhelm a child or that are unpredictable may undermine
emotional regulation development. Effective strategies involve working
with a child to support developing self-control such as modeling a
desired behavior rather than demanding it.
The richness of an environment that a child is exposed to helps
the development of emotional regulation. An environment must provide
appropriate levels of freedom and constraint. The environment must allow
opportunities for a child to practice self-regulation. An environment
with opportunities to practice social skills without overstimulation or
excessive frustration helps a child develop self-regulation skills.
Substance use
Several
variables have been explored to explain the connection between
emotional dysregulation and substance use in young adults, such as child
maltreatment, cortisol levels, family environment, and symptoms of
depression and anxiety. Vilhena-Churchill and Goldstein (2014)
explored the association between childhood maltreatment and emotional
dysregulation. More severe childhood maltreatment was found to be
associated with an increase in difficulty regulating emotion, which in
turn was associated with a greater likelihood of coping by using
marijuana. Kliewer et al. (2016)
performed a study on the relationship between negative family emotional
climate, emotional dysregulation, blunted anticipatory cortisol, and
substance use in adolescents. Increased negative family emotional
climate was found to be associated with high levels of emotional
dysregulation, which was then associated with increased substance use.
Girls were seen to have blunted anticipatory cortisol levels, which was
also associated with an increase in substance use. Childhood events and
family climate with emotional dysregulation are both factors seemingly
linked to substance use. Prosek, Giordano, Woehler, Price, and
McCullough (2018)
explored the relationship between mental health and emotional
regulation in collegiate illicit substance users. Illicit drug users
reported higher levels of depression and anxiety symptoms. Emotional
dysregulation was more prominent in illicit drug users in the sense that
they had less clarity and were less aware of their emotions when the
emotions were occurring.
Many people experience dysregulation and can struggle at times with
uncontrollable emotions. Thus, potential underlying issues are
important to consider in determining severity.
As the ability to appropriately express and regulate emotions is
related to better relationships and mental health, parental support can
help regulate the emotions of children struggling with emotional
dysregulation. Training to help parents address this issue focuses on
predictability and consistency. These tenets are thought to provide
comfort by creating a sense of familiarity and thus safety.
While cognitive behavioral therapy
is the most widely prescribed treatment for such psychiatric disorders,
a commonly prescribed psychotherapeutic treatment for emotional
dysregulation is dialectical behavioral therapy, a psychotherapy which promotes the use of mindfulness, a concept called dialectics, and emphasis on the importance of validation and maintaining healthy behavioral habits.
When diagnosed as being part of ADHD, norepinephrine and dopamine reuptake inhibitors such as methylphenidate (Ritalin) and atomoxetine
are often used. A few studies have also showed promise in terms of
non-pharmacological treatments for people with ADHD and emotional
problems,although the research is limited and requires additional inquiry.
Eye Movement Desensitization and Reprocessing (EMDR) can help recovery from emotional dysregulation in cases where the dysregulation is a symptom of prior trauma.
Outside of therapy, there are helpful strategies to help individuals
recognize how they are feeling and put space between an event and their
response. These include mindfulness, affirmations, and gratitude journaling. Hypnosis may also help to improve emotional regulation.
Movement such as yoga and aerobic exercise can also be therapeutic by
aiding with regulation and the ability to understand how one's mind
influences behavior.
Mars' cloudy sky as seen by Perseverance rover in 2023, sol 738.
The climate of Mars has been a topic of scientific curiosity for centuries, in part because it is the only terrestrial planet whose surface can be easily directly observed in detail from Earth with help from a telescope.
Although Mars is smaller than Earth with only one tenth of Earth's mass, and 50% farther from the Sun than Earth, its climate has important similarities, such as the presence of polar ice caps, seasonal changes and observable weather patterns. It has attracted sustained study from planetologists and climatologists. While Mars's climate has similarities to Earth's, including periodic ice ages, there are also important differences, such as much lower thermal inertia. Mars' atmosphere has a scale height
of approximately 11 km (36,000 ft), 60% greater than that on Earth. The
climate is of considerable relevance to the question of whether life is
or ever has been present on the planet.
Mars has been studied by Earth-based instruments since the 17th century, but it is only since the exploration of Mars
began in the mid-1960s that close-range observation has been possible.
Flyby and orbital spacecraft have provided data from above, while
landers and rovers have measured atmospheric conditions directly.
Advanced Earth-orbital instruments today continue to provide some useful
"big picture" observations of relatively large weather phenomena.
The first Martian flyby mission was Mariner 4,
which arrived in 1965. That quick two-day pass (July 14–15, 1965) with
crude instruments contributed little to the state of knowledge of
Martian climate. Later Mariner missions (Mariner 6 and 7) filled in some of the gaps in basic climate information. Data-based climate studies started in earnest with the Viking program landers in 1975 and continue with such probes as the Mars Reconnaissance Orbiter.
This observational work has been complemented by a type of scientific computer simulation called the Mars general circulation model. Several different iterations of MGCM have led to an increased understanding of Mars as well as the limits of such models.
Historical climate observations
Giacomo Maraldi determined in 1704 that the southern cap is not centered on the rotational pole of Mars. During the opposition of 1719, Maraldi observed both polar caps and temporal variability in their extent.
William Herschel was the first to deduce the low density of the Martian atmosphere in his 1784 paper entitled On
the remarkable appearances at the polar regions on the planet Mars, the
inclination of its axis, the position of its poles, and its spheroidal
figure; with a few hints relating to its real diameter and atmosphere.
When Mars appeared to pass close by two faint stars with no effect on
their brightness, Herschel correctly concluded that this meant that
there was little atmosphere around Mars to interfere with their light.
Honore Flaugergues's 1809 discovery of "yellow clouds" on the surface of Mars is the first known observation of Martian dust storms.
Flaugergues also observed in 1813 significant polar-ice waning during
Martian springtime. His speculation that this meant that Mars was warmer
than Earth proved inaccurate.
Recent observations and modeling are producing information not only
about the present climate and atmospheric conditions on Mars but also
about its past. The Noachian-era Martian atmosphere had long been
theorized to be carbon dioxide–rich. Recent spectral observations of deposits of clay minerals on Mars and modeling of clay mineral formation conditions have found that there is little to no carbonate present in clay
of that era. Clay formation in a carbon dioxide–rich environment is
always accompanied by carbonate formation, although the carbonate may
later be dissolved by volcanic acidity.
The discovery of water-formed minerals on Mars including hematite and jarosite, by the Opportunity rover and goethite by the Spirit rover, has led to the conclusion that climatic conditions in the distant past allowed for free-flowing water on Mars. The morphology of some crater impacts on Mars indicate that the ground was wet at the time of impact. Geomorphic observations of both landscape erosion rates and Martian valley networks
also strongly imply warmer, wetter conditions on Noachian-era Mars
(earlier than about four billion years ago). However, chemical analysis
of Martian meteorite
samples suggests that the ambient near-surface temperature of Mars has
most likely been below 0 °C (32 °F) for the last four billion years.
Some scientists maintain that the great mass of the Tharsis
volcanoes has had a major influence on Mars' climate. Erupting
volcanoes give off great amounts of gas, mainly water vapor and CO2.
Enough gas may have been released by volcanoes to have made the earlier
Martian atmosphere thicker than Earth's. The volcanoes could also have
emitted enough H2O to cover the whole Martian surface to a depth of 120 m (390 ft). Carbon dioxide is a greenhouse gas that raises a planet's temperature: it traps heat by absorbing infrared radiation. Thus, Tharsis volcanoes, by giving off CO2,
could have made Mars more Earth-like in the past. Mars may have once
had a much thicker and warmer atmosphere, and oceans or lakes may have
been present. It has, however, proven extremely difficult to construct convincing global climate models for Mars which produce temperatures above 0 °C (32 °F) at any point in its history, although this may simply reflect problems in accurately calibrating such models.
Evidence of a geologically recent, extreme ice age on Mars was
published in 2016. Just 370,000 years ago, the planet would have
appeared more white than red.
Mars' temperature and circulation vary every Martian year (as expected for any planet with an atmosphere and axial tilt). Mars lacks oceans, a source of much interannual variation on Earth. Mars Orbiter Camera data beginning in March 1999 and covering 2.5 Martian years
show that Martian weather tends to be more repeatable and hence more
predictable than that of Earth. If an event occurs at a particular time
of year in one year, the available data (sparse as it is) indicates that
it is fairly likely to repeat the next year at nearly the same
location, give or take a week.
On September 29, 2008, the Phoenix lander detected snow falling from clouds 4.5 kilometres (2.8 mi) above its landing site near Heimdal Crater. The precipitation vaporised before reaching the ground, a phenomenon called virga.
Precipitated water ice covering the Martian plain Utopia Planitia, the water ice precipitated by adhering to dry ice (observed by the Viking 2 lander)
Clouds
Ice clouds moving above the Phoenix landing site over a period of 10 minutes (August 29, 2008)
Martian dust storms
can kick up fine particles in the atmosphere around which clouds can
form. These clouds can form very high up, up to 100 km (62 mi) above the
planet. As well as Martian Dust Storms, clouds can naturally form as a result of dry ice formation or water and ice.
Furthermore, rarer "Mother of Pearl" clouds have formed when all
particles of a cloud form at the same time, creating stunning iridescent
clouds. The first images of Mars sent by Mariner 4
showed visible clouds in Mars' upper atmosphere. The clouds are very
faint and can only be seen reflecting sunlight against the darkness of
the night sky. In that respect, they look similar to mesospheric clouds,
also known as noctilucent clouds, on Earth, which occur about 80 km (50 mi) above our planet.
Temperature
Measurements of Martian temperature predate the Space Age. However, early instrumentation and techniques of radio astronomy produced crude, differing results. Early flyby probes (Mariner 4) and later orbiters used radio occultation to perform aeronomy. With chemical composition already deduced from spectroscopy, temperature and pressure could then be derived. Nevertheless, flyby occultations can only measure properties along two transects,
at their trajectories' entries and exits from Mars' disk as seen from
Earth. This results in weather "snapshots" at a particular area, at a
particular time. Orbiters then increase the number of radio transects.
Later missions, starting with the dual Mariner 6 and 7 flybys, plus the Soviet Mars 2 and 3, carried infrared detectors to measure radiant energy.
Mariner 9 was the first to place an infrared radiometer and
spectrometer in Mars orbit in 1971, along with its other instruments and
radio transmitter. Viking 1 and 2 followed, with not merely Infrared Thermal Mappers (IRTM). The missions could also corroborate these remote sensing datasets with not only their in situ lander metrology booms, but with higher-altitude temperature and pressure sensors for their descent.
Differing in situ values have been reported for the average temperature on Mars, with a common value being −63 °C (210 K; −81 °F).
Surface temperatures may reach a high of about 20 °C (293 K; 68 °F) at
noon, at the equator, and a low of about −153 °C (120 K; −243 °F) at
the poles.
Actual temperature measurements at the Viking landers' site range from
−17.2 °C (256.0 K; 1.0 °F) to −107 °C (166 K; −161 °F). The warmest soil
temperature estimated by the Viking Orbiter was 27 °C (300 K; 81 °F).
The Spirit rover recorded a maximum daytime air temperature in the
shade of 35 °C (308 K; 95 °F), and regularly recorded temperatures well
above 0 °C (273 K; 32 °F), except in winter.
It has been reported that "On the basis of the nighttime air
temperature data, every northern spring and early northern summer yet
observed were identical to within the level of experimental error (to
within ±1 °C)" but that the "daytime data, however, suggests a somewhat
different story, with temperatures varying from year-to-year by up to
6 °C in this season.
This day-night discrepancy is unexpected and not understood". In
southern spring and summer, variance is dominated by dust storms which
increase the value of the night low temperature and decrease the daytime
peak temperature.
This results in a small (20 °C) decrease in average surface
temperature, and a moderate (30 °C) increase in upper atmosphere
temperature.
Before and after the Viking missions, newer, more advanced
Martian temperatures were determined from Earth via microwave
spectroscopy. As the microwave beam, of under 1 arcminute, is larger
than the disk of the planet, the results are global averages. Later, the Mars Global Surveyor's Thermal Emission Spectrometer and to a lesser extent 2001 Mars Odyssey's THEMIS could not merely reproduce infrared measurements but intercompare lander, rover, and Earth microwave data. The Mars Reconnaissance Orbiter's Mars Climate Sounder can similarly derive atmospheric profiles.
The datasets "suggest generally colder atmospheric temperatures and
lower dust loading in recent decades on Mars than during the Viking
Mission," although Viking data had previously been revised downward.
The TES data indicates "Much colder (10–20 K) global atmospheric
temperatures were observed during the 1997 versus 1977 perihelion
periods" and "that the global aphelion atmosphere of Mars is colder,
less dusty, and cloudier than indicated by the established Viking
climatology," again, taking into account the Wilson and Richardson
revisions to Viking data.
A later comparison, while admitting "it is the microwave record
of air temperatures which is the most representative," attempted to
merge the discontinuous spacecraft record. No measurable trend in global
average temperature between Viking IRTM and MGS TES was visible.
"Viking and MGS air temperatures are essentially indistinguishable for
this period, suggesting that the Viking and MGS eras are characterized
by essentially the same climatic state." It found "a strong dichotomy"
between the northern and southern hemispheres, a "very asymmetric
paradigm for the Martian annual cycle: a northern spring and summer
which is relatively cool, not very dusty, and relatively rich in water
vapor and ice clouds; and a southern summer rather similar to that
observed by Viking with warmer air temperatures, less water vapor and
water ice, and higher levels of atmospheric dust."
The Mars Reconnaissance Orbiter
MCS (Mars Climate Sounder) instrument was, upon arrival, able to
operate jointly with MGS for a brief period; the less-capable Mars
Odyssey THEMIS and Mars Express SPICAM datasets may also be used to span
a single, well-calibrated record. While MCS and TES temperatures are
generally consistent,
investigators report possible cooling below the analytical precision.
"After accounting for this modeled cooling, MCS MY 28 temperatures are
an average of 0.9 (daytime) and 1.7 K (night-time) cooler than TES MY 24
measurements."
It has been suggested that Mars had a much thicker, warmer atmosphere early in its history.
Much of this early atmosphere would have consisted of carbon dioxide.
Such an atmosphere would have raised the temperature, at least in some
places, to above the freezing point of water.
With the higher temperature running water could have carved out the
many channels and outflow valleys that are common on the planet. It
also may have gathered together to form lakes and maybe an ocean.
Some researchers have suggested that the atmosphere of Mars may have
been many times as thick as the Earth's; however research published in
September 2015 advanced the idea that perhaps the early Martian
atmosphere was not as thick as previously thought.
Currently, the atmosphere is very thin. For many years, it was
assumed that as with the Earth, most of the early carbon dioxide was
locked up in minerals, called carbonates. However, despite the use of
many orbiting instruments that looked for carbonates, very few carbonate
deposits have been found. Today, it is thought that much of the carbon dioxide in the Martian air was removed by the solar wind. Researchers have discovered a two-step process that sends the gas into space.
Ultraviolet light from the Sun could strike a carbon dioxide molecule,
breaking it into carbon monoxide and oxygen. A second photon of
ultraviolet light could subsequently break the carbon monoxide into
oxygen and carbon which would get enough energy to escape the planet.
In this process the light isotope of carbon (12C)
would be most likely to leave the atmosphere. Hence, the carbon
dioxide left in the atmosphere would be enriched with the heavy isotope (13C). This higher level of the heavy isotope is what was found by the Curiosity rover on Mars.
Climate data for the Gale Crater is provided here below, with the seasons normalized to those of Earth.
The Martian atmosphere is composed mainly of carbon dioxide and has a mean surface pressure of about 600 pascals
(Pa), much lower than the Earth's 101,000 Pa. One effect of this is
that Mars' atmosphere can react much more quickly to a given energy
input than Earth's atmosphere. As a consequence, Mars is subject to strong thermal tides
produced by solar heating rather than a gravitational influence. These
tides can be significant, being up to 10% of the total atmospheric
pressure (typically about 50 Pa). Earth's atmosphere experiences similar
diurnal and semidiurnal tides but their effect is less noticeable
because of Earth's much greater atmospheric mass.
Although the temperature on Mars can reach above freezing, liquid
water is unstable over much of the planet, as the atmospheric pressure
is below water's triple point and water ice sublimes into water vapor. Exceptions to this are the low-lying areas of the planet, most notably in the Hellas Planitia impact basin, the largest such crater on Mars. It is so deep that the atmospheric pressure at the bottom reaches 1155 Pa, which is above the triple point, so if the temperature exceeded the local freezing point, liquid water could exist there.
The surface of Mars has a very low thermal inertia,
which means it heats quickly when the sun shines on it. Typical daily
temperature swings, away from the polar regions, are around 100 K. On
Earth, winds often develop in areas where thermal inertia changes
suddenly, such as from sea to land. There are no seas on Mars, but there
are areas where the thermal inertia of the soil changes, leading to
morning and evening winds akin to the sea breezes on Earth.
The Antares project "Mars Small-Scale Weather" (MSW) has recently
identified some minor weaknesses in current global climate models (GCMs)
due to the GCMs' more primitive soil modeling. "Heat admission to the
ground and back is quite important in Mars, so soil schemes have to be
quite accurate."
Those weaknesses are being corrected and should lead to more accurate
future assessments, but make continued reliance on older predictions of
modeled Martian climate somewhat problematic.
At low latitudes the Hadley circulation dominates, and is essentially the same as the process which on Earth generates the trade winds. At higher latitudes a series of high and low pressure areas, called baroclinic
pressure waves, dominate the weather. Mars is drier and colder than
Earth, and in consequence dust raised by these winds tends to remain in
the atmosphere longer than on Earth as there is no precipitation to wash
it out (excepting CO2 snowfall). One such cyclonic storm was recently captured by the Hubble Space Telescope (pictured below).
One of the major differences between Mars' and Earth's Hadley circulations is their speed which is measured on an overturning timescale. The overturning timescale on Mars is about 100 Martian days while on Earth, it is over a year.
Katabatic Winds and Jumps
Katabatic winds,
or drainage atmospheric flows, are winds that are created by cooled
dense air sinking and accelerating down sloping terrains through
gravitational force.
Found most commonly on Earth effecting the elevated ice sheets of
Greenland and Antarctica, katabatic winds can also be found effecting
parts of Mars with intense clear-cut downslope circulations, such as
Valles Marineris, Olympus Mons, and both the northern and southern polar
cap.
They can be identified by multiple different surface morphological
features in the polar regions, such as dune fields and frost streaks. Due to the low thermal inertia of Mars' thin CO2
atmosphere and the short radiative timescales, katabatic winds on Mars
are two to three times stronger than those on Earth and take place on
large areas of land with weak ambient winds, sloping terrain, and
near-surface temperature inversions or radiative cooling of the surface
and atmosphere.
Katabatic winds have been instrumental in shaping the northern polar
cap and the polar layered deposits, both in aeolian methodology and
thermal methodology.
It has also been shown that the acceleration of katabatic winds
increases with the steepness of the slope and causes atmospheric warming
the more intense the slope is. This atmospheric warming could appear over any steep slope, but this does not always equal surface warming. They also are shown to limit CO2 condensation rates on the polar caps in the winter and increase CO2 sublimation in the summer.
Though quantitative measurements of katabatic winds are rarely
available, they remain a highly sought-after element for upcoming
missions.
Katabatic jumps are also common in troughs on Mars and can be
described as narrow zones with large horizontal changes in pressure,
temperature, and wind speed that require super saturated water vapor to
form clouds and enable ice migration from the upstream part of the
trough to the downstream.
For this reason, the polar caps see less katabatic jumps in winter, as
the seasonal ice cap that covers the polar regions means there is less
water ice available to create vapor.
However, even when the seasonal cap has sublimated over the course of
the Martian summer, the fast winds necessary for katabatic jumps are no
longer present, meaning the cloud cover is again negligible. Therefore, katabatic jumps are most commonly seen in troughs during the Martian spring and Martian fall.
When the Mariner 9
probe arrived at Mars in 1971, scientists expected to see crisp new
pictures of surface detail. Instead they saw a near planet-wide dust
storm with only the giant volcano Olympus Mons
showing above the haze. The storm lasted for a month, an occurrence
scientists have since learned is quite common on Mars. Using data from
Mariner 9, James B. Pollack et al. proposed a mechanism for Mars dust storms in 1973.
Time-lapse composite of the Martian horizon as seen by the Opportunity
rover over 30 Martian days; it shows how much sunlight the July 2007
dust storms blocked; Tau of 4.7 indicates 99% sunlight was blocked.
As observed by the Viking spacecraft from the surface,
"during a global dust storm the diurnal temperature range narrowed
sharply, from 50°C to about 10°C, and the wind speeds picked up
considerably—indeed, within only an hour of the storm's arrival they had
increased to 17 m/s (61 km/h), with gusts up to 26 m/s (94 km/h).
Nevertheless, no actual transport of material was observed at either
site, only a gradual brightening and loss of contrast of the surface
material as dust settled onto it."
On June 26, 2001, the Hubble Space Telescope spotted a dust storm
brewing in Hellas Basin
on Mars (pictured right). A day later the storm "exploded" and became a
global event. Orbital measurements showed that this dust storm reduced
the average temperature of the surface and raised the temperature of the
atmosphere of Mars by 30 K.
The low density of the Martian atmosphere means that winds of 18 to
22 m/s (65 to 79 km/h) are needed to lift dust from the surface, but
since Mars is so dry, the dust can stay in the atmosphere far longer
than on Earth, where it is soon washed out by rain. The season
following that dust storm had daytime temperatures 4 K below average.
This was attributed to the global covering of light-colored dust that
settled out of the dust storm, temporarily increasing Mars' albedo.
In mid-2007 a planet-wide dust storm posed a serious threat to the solar-powered Spirit and OpportunityMars Exploration Rovers
by reducing the amount of energy provided by the solar panels and
necessitating the shut-down of most science experiments while waiting
for the storms to clear. Following the dust storms, the rovers had significantly reduced power due to settling of dust on the arrays.
Mars
without a dust storm in June 2001 (on left) and with a global dust
storm in July 2001 (on right), as seen by Mars Global Surveyor
Dust storms are most common during perihelion, when the planet receives 40 percent more sunlight than during aphelion.
During aphelion water ice clouds form in the atmosphere, interacting
with the dust particles and affecting the temperature of the planet.
A large intensifying dust storm began in late-May 2018 and had
persisted as of mid-June. By June 10, 2018, as observed at the location
of the rover Opportunity, the storm was more intense than the 2007 dust storm endured by Opportunity. On June 20, 2018, NASA reported that the dust storm had grown to completely cover the entire planet.
Observation since the 1950s has shown that the chances of a
planet-wide dust storm in a particular Martian year are approximately
one in three.
Dust storms contribute to water loss on Mars. A study of dust storms with the Mars Reconnaissance Orbiter
suggested that 10 percent of the water loss from Mars may have been
caused by dust storms. Instruments on board the Mars Reconnaissance
Orbiter detected observed water vapor at very high altitudes during
global dust storms. Ultraviolet light from the sun can then break the
water apart into hydrogen and oxygen. The hydrogen from the water
molecule then escapes into space. The most recent loss of atomic hydrogen from water was found to be largely driven by seasonal processes and dust storms that transport water directly to the upper atmosphere.
Atmospheric electricity
It is thought that Martian dust storms can lead to atmospheric electrical phenomena. Dust grains are known to become electrically charged upon colliding with the ground or with other grains.
Theoretical, computational and experimental analyses of lab-scale dusty
flows and full-scale dust devils on Earth indicate that self-induced
electricity, including lightning, is a common phenomenon in turbulent
flows laden with dust.
On Mars, this tendency would be compounded by the low pressure of the
atmosphere, which would translate into much lower electric fields
required for breakdown. As a result, aerodynamic segregation of dust at
both meso- and macro-scales could easily lead to a sufficiently large
separation of charges to produce local electrical breakdown in dust
clouds above the ground.
Direct
Numerical Simulation of turbulence laden with 168 million electrically
charged inertial dust particles (Center for Turbulence Research,
Stanford University)
Nonetheless, in contrast
to other planets in the Solar System, no in-situ measurements exist on
the surface of Mars to prove these hypotheses. The first attempt to elucidate these unknowns was made by the Schiaparelli EDM lander
of the ExoMars mission in 2016, which included relevant onboard
hardware to measure dust electric charges and atmospheric electric
fields on Mars. However, the lander failed during the automated landing
on October 19, 2016, and crashed on the surface of Mars.
Saltation
The process of geological saltation
is quite important on Mars as a mechanism for adding particulates to
the atmosphere. Saltating sand particles have been observed on the MER Spirit rover.
Theory and real world observations have not agreed with each other,
classical theory missing up to half of real-world saltating particles.
A model more closely in accord with real world observations suggests
that saltating particles create an electrical field that increases the
saltation effect. Mars grains saltate in 100 times higher and longer
trajectories and reach 5–10 times higher velocities than Earth grains
do.
Repeating northern annular cloud
Hubble view of the colossal polar cloud on Mars
A large doughnut shaped cloud appears in the north polar region of
Mars around the same time every Martian year and of about the same size. It forms in the morning and dissipates by the Martian afternoon. The outer diameter of the cloud is roughly 1,600 km (1,000 mi), and the inner hole or eye is 320 km (200 mi) across. The cloud is thought to be composed of water-ice, so it is white in color, unlike the more common dust storms.
It looks like a cyclonic storm, similar to a hurricane, but it does not rotate.
The cloud appears during the northern summer and at high latitude.
Speculation is that this is due to unique climate conditions near the
northern pole.
Cyclone-like storms were first detected during the Viking orbital
mapping program, but the northern annular cloud is nearly three times
larger. The cloud has also been detected by various probes and telescopes including the Hubble and Mars Global Surveyor.
Other repeating events are dust storms and dust devils.
The source of Mars methane is unknown; its detection is shown here.
Methane (CH4)
is chemically unstable in the current oxidizing atmosphere of Mars. It
would quickly break down due to ultraviolet radiation from the Sun and
chemical reactions with other gases. Therefore, a persistent presence of
methane in the atmosphere may imply the existence of a source to
continually replenish the gas.
Trace amounts of methane, at the level of several parts per billion (ppb), were first reported in Mars' atmosphere by a team at the NASA Goddard Space Flight Center in 2003.
Large differences in the abundances were measured between observations
taken in 2003 and 2006, which suggested that the methane was locally
concentrated and probably seasonal. In 2014, NASA reported that the Curiosity
rover detected a tenfold increase ('spike') in methane in the
atmosphere around it in late 2013 and early 2014. Four measurements
taken over two months in this period averaged 7.2 ppb, implying that
Mars is episodically producing or releasing methane from an unknown
source. Before and after that, readings averaged around one-tenth that level. On 7 June 2018, NASA announced a cyclical seasonal variation in the background level of atmospheric methane.
Curiosity rover detected a cyclical seasonal variation in atmospheric methane.
The principal candidates for the origin of Mars' methane include non-biological processes such as water-rock reactions, radiolysis of water, and pyrite formation, all of which produce H2 that could then generate methane and other hydrocarbons via Fischer–Tropsch synthesis with CO and CO2. It has also been shown that methane could be produced by a process involving water, carbon dioxide, and the mineral olivine, which is known to be common on Mars.
Mars Reconnaissance Orbiter images suggest an unusual erosion effect occurs based on Mars' unique climate. Spring warming in certain areas leads to CO2 ice subliming and flowing upwards, creating highly unusual erosion patterns called "spider gullies". Translucent CO2 ice forms over winter and as the spring sunlight warms the surface, it vaporizes the CO2 to gas which flows uphill under the translucent CO2 ice. Weak points in that ice lead to CO2 geysers.
Martian storms are significantly affected by Mars' large mountain ranges. Individual mountains like record holding Olympus Mons (26 km (85,000 ft)) can affect local weather but larger weather effects are due to the larger collection of volcanoes in the Tharsis region.
One unique repeated weather phenomenon involving mountains is a spiral dust cloud that forms over Arsia Mons. The spiral dust cloud over Arsia Mons can tower 15 to 30 km (49,000 to 98,000 ft) above the volcano. Clouds are present around Arsia Mons throughout the Martian year, peaking in late summer.
Clouds surrounding mountains display a seasonal variability. Clouds at Olympus Mons and Ascreaus Mons appear in northern hemisphere spring and summer, reaching a total maximum area of approximately 900,000 km2 and 1,000,000 km2 respectively in late spring. Clouds around Alba Patera and Pavonis Mons show an additional, smaller peak in late summer. Very few clouds were observed in winter. Predictions from the Mars General Circulation Model are consistent with these observations.
Polar caps
Polar ice cap with the depth of the atmosphere, as well as a large orographic cloud visible at the horizonHow Mars might have looked during an ice age between 2.1 million and 400,000 years ago, when Mars' axial tilt is thought to have been larger than today.HiRISE view of Olympia Rupes in Planum Boreum, one of many exposed water ice layers found in the polar regions of Mars. Depicted width: 1.3 km (0.8 miles).HiRISE image of "dark dune spots" and fans formed by eruptions of CO2 gas geysers on Mars' south polar ice sheet
Mars has ice caps at its north pole and south pole, which consist mainly of water ice; however, there is frozen carbon dioxide (dry ice) present on their surfaces. Dry ice accumulates in the north polar region (Planum Boreum)
in winter only, subliming completely in summer, while the south polar
region additionally has a permanent dry ice cover up to eight meters
(25 feet) thick. This difference is due to the higher elevation of the south pole.
Much of the atmosphere can condense at the winter pole so that
the atmospheric pressure can vary by up to a third of its mean value.
This condensation and evaporation will cause the proportion of the
noncondensable gases in the atmosphere to change inversely.
The eccentricity of Mars' orbit affects this cycle, as well as other
factors. In the spring and autumn wind due to the carbon dioxide
sublimation process is so strong that it can be a cause of the global
dust storms mentioned above.
The northern polar cap has a diameter of approximately 1,000 km during the northern Mars summer,
and contains about 1.6 million cubic kilometres of ice, which if spread evenly on the cap would be 2 km thick. (This compares to a volume of 2.85 million cubic kilometres for the Greenland ice sheet.) The southern polar cap has a diameter of 350 km and a maximum thickness of 3 km.
Both polar caps show spiral troughs, which were initially thought to
form as a result of differential solar heating, coupled with the
sublimation of ice and condensation of water vapor. Recent analysis of ice penetrating radar data from SHARAD has demonstrated that the spiral troughs are formed from a unique situation in which high density katabatic winds descend from the polar high to transport ice and create large wavelength bedforms. The spiral shape comes from Coriolis effect
forcing of the winds, much like winds on earth spiral to form a
hurricane. The troughs did not form with either ice cap; instead they
began to form between 2.4 million and 500,000 years ago, after
three-fourths of the ice cap was in place. This suggests that a
climatic shift allowed for their onset. Both polar caps shrink and
regrow following the temperature fluctuation of the Martian seasons;
there are also longer-term trends that are better understood in the modern era.
During the southern hemisphere spring, solar heating of dry ice
deposits at the south pole leads in places to accumulation of
pressurized CO2 gas below the surface of the semitransparent
ice, warmed by absorption of radiation by the darker substrate. After
attaining the necessary pressure, the gas bursts through the ice in
geyser-like plumes. While the eruptions have not been directly observed,
they leave evidence in the form of "dark dune spots" and lighter fans
atop the ice, representing sand and dust carried aloft by the eruptions,
and a spider-like pattern of grooves created below the ice by the
outrushing gas. (see Geysers on Mars.) Eruptions of nitrogen gas observed by Voyager 2 on Triton are thought to occur by a similar mechanism.
Both polar caps are currently accumulating, confirming predicted Milankovich cycling on timescales of ~400,000 and ~4,000,000 years. Soundings by the Mars Reconnaissance Orbiter SHARAD indicate total cap growth of ~0.24 km3/year. Of this, 92%, or ~0.86 mm/year, is going to the north, as Mars' offset Hadley circulation acts as a nonlinear pump of volatiles northward.
Solar wind
Mars lost most of its magnetic field about four billion years ago. As a result, solar wind and cosmic radiation
interacts directly with the Martian ionosphere. This keeps the
atmosphere thinner than it would otherwise be by solar wind action
constantly stripping away atoms from the outer atmospheric layer.
Most of the historical atmospheric loss on Mars can be traced back to
this solar wind effect. Current theory posits a weakening solar wind and
thus today's atmosphere stripping effects are much less than those in
the past when the solar wind was stronger.
In spring, sublimation of ice causes sand from below the ice layer to form fan-shaped deposits on top of the seasonal ice.
Mars has an axial tilt of 25.2°. This means that there are seasons on Mars, just as on Earth. The eccentricity
of Mars' orbit is 0.1, much greater than the Earth's present orbital
eccentricity of about 0.02. The large eccentricity causes the insolation on Mars to vary as the planet orbits the Sun. (The Martian year lasts 687 days, roughly 2 Earth years.) As on Earth, Mars' obliquity
dominates the seasons but, because of the large eccentricity, winters
in the southern hemisphere are long and cold while those in the north
are short and relatively warm.
It is now thought that ice accumulated when Mars' orbital tilt
was very different from what it is now. (The axis the planet spins on
has considerable "wobble", meaning its angle changes over time.)
A few million years ago, the tilt of the axis of Mars was 45 degrees
instead of its present 25 degrees. Its tilt, also called obliquity,
varies greatly because its two tiny moons cannot stabilize it like
Earth's moon.
Many features on Mars, especially in the Ismenius Lacus
quadrangle, are thought to contain large amounts of ice. The most
popular model for the origin of the ice is climatic change from large changes in the tilt of the planet's rotational axis. At times the tilt has even been greater than 80 degrees. Large changes in the tilt explains many ice-rich features on Mars.
Studies have shown that when the tilt of Mars reaches 45 degrees
from its current 25 degrees, ice is no longer stable at the poles.
Furthermore, at this high tilt, stores of solid carbon dioxide (dry
ice) sublimate, thereby increasing the atmospheric pressure. This
increased pressure allows more dust to be held in the atmosphere.
Moisture in the atmosphere will fall as snow or as ice frozen onto dust
grains. Calculations suggest this material will concentrate in the
mid-latitudes. General circulation models of the Martian atmosphere predict
accumulations of ice-rich dust in the same areas where ice-rich features
are found.
When the tilt begins to return to lower values, the ice sublimates (turns directly to a gas) and leaves behind a lag of dust. The lag deposit caps the underlying material so with each cycle of high tilt levels, some ice-rich mantle remains behind.
Note, that the smooth surface mantle layer probably represents only
relative recent material. Below are images of layers in this smooth
mantle that drops from the sky at times.
Smooth mantle covers parts of a crater in the Phaethontis quadrangle. Layering suggests the mantle was deposited multiple times.
Enlargement of previous image of mantle layers. Four to five layers are visible. Picture taken under HiWish program.
Present unequal lengths of the seasons
Season
Mars' Sols
Earth Days
Northern spring, southern autumn
193.30
92.764
Northern summer, southern winter
178.64
93.647
Northern autumn, southern spring
142.70
89.836
Northern winter, southern summer
153.95
88.997
Precession
in the alignment of the obliquity and eccentricity lead to global
warming and cooling ('great' summers and winters) with a period of
170,000 years.
Like Earth, the obliquity
of Mars undergoes periodic changes which can lead to long-lasting
changes in climate. Once again, the effect is more pronounced on Mars
because it lacks the stabilizing influence of a large moon. As a result,
the obliquity can alter by as much as 45°. Jacques Laskar, of France's
National Centre for Scientific Research, argues that the effects of
these periodic climate changes can be seen in the layered nature of the
ice cap at the Martian north pole. Current research suggests that Mars is in a warm interglacial period which has lasted more than 100,000 years.
Because the Mars Global Surveyor
was able to observe Mars for 4 Martian years, it was found that Martian
weather was similar from year to year. Any differences were directly
related to changes in the solar energy that reached Mars. Scientists
were even able to accurately predict dust storms that would occur during
the landing of Beagle 2. Regional dust storms were discovered to be closely related to where dust was available.
Evidence for recent climatic change
Pits in south polar ice cap (MGS 1999, NASA)
There have been regional changes around the south pole (Planum Australe) over the past few Martian years. In 1999 the Mars Global Surveyor
photographed pits in the layer of frozen carbon dioxide at the Martian
south pole. Because of their striking shape and orientation these pits
have become known as swiss cheese features.
In 2001 the craft photographed the same pits again and found that they
had grown larger, retreating about 3 meters in one Martian year.
These features are caused by the sublimation of the dry ice layer,
thereby exposing the inert water ice layer. More recent observations
indicate that the ice at Mars' south pole is continuing to sublimate.
The pits in the ice continue to grow by about 3 meters per Martian year.
Malin states that conditions on Mars are not currently conducive to the
formation of new ice. A NASA press release indicates that "climate change [is] in progress" on Mars.
In a summary of observations with the Mars Orbiter Camera, researchers
speculated that some dry ice may have been deposited between the Mariner 9 and the Mars Global Surveyor mission. Based on the current rate of loss, the deposits of today may be gone in a hundred years.
Elsewhere on the planet, low latitude areas have more water ice than they should have given current climatic conditions.
Mars Odyssey "is giving us indications of recent global climate change
in Mars", said Jeffrey Plaut, project scientist for the mission at
NASA's Jet Propulsion Laboratory, in non-peer reviewed published work in
2003.
Attribution theories
Polar changes
Colaprete
et al. conducted simulations with the Mars General Circulation Model
which show that the local climate around the Martian south pole may
currently be in an unstable period. The simulated instability is rooted
in the geography of the region, leading the authors to speculate that
the sublimation of the polar ice is a local phenomenon rather than a
global one.
The researchers showed that even with a constant solar luminosity the
poles were capable of jumping between states of depositing or losing
ice. The trigger for a change of states could be either increased dust
loading in the atmosphere or an albedo change due to deposition of water
ice on the polar cap. This theory is somewhat problematic due to the lack of ice depositation after the 2001 global dust storm.
Another issue is that the accuracy of the Mars General Circulation
Model decreases as the scale of the phenomenon becomes more local.
It has been argued that "observed regional changes in south polar
ice cover are almost certainly due to a regional climate transition,
not a global phenomenon, and are demonstrably unrelated to external
forcing." Writing in a Nature
news story, Chief News and Features Editor Oliver Morton said "The
warming of other solar bodies has been seized upon by climate sceptics.
On Mars, the warming seems to be down to dust blowing around and
uncovering big patches of black basaltic rock that heat up in the day."
Habitability
Though at its current state, Mars is unhabitable to humans, many people have suggested terraforming Mars to change the climate to make it more habitable to humans. Notably, Elon Musk has suggested detonating nuclear weapons on the ice caps of Mars to release water vapor and carbon dioxide,
which could warm the planet significantly enough to possibly make it
habitable for humans, though it has been disputed by recent research.
Climate zones
Terrestrial Climate zones first have been defined by Wladimir Köppen
based on the distribution of vegetation groups. Climate classification
is furthermore based on temperature, rainfall, and subdivided based upon
differences in the seasonal distribution of temperature and
precipitation; and a separate group exists for extrazonal climates like
in high altitudes. Mars has neither vegetation nor rainfall, so any
climate classification could be only based upon temperature; a further
refinement of the system may be based on dust distribution, water vapor
content, occurrence of snow. Solar Climate Zones can also be easily defined for Mars.
Current missions
The 2001 Mars Odyssey
is currently orbiting Mars and taking global atmospheric temperature
measurements with the TES instrument. The Mars Reconnaissance Orbiter
is currently taking daily weather and climate related observations from
orbit. One of its instruments, the Mars climate sounder is specialized for climate observation work.
The MSL was launched in November 2011 and landed on Mars on August 6, 2012. Orbiters MAVEN, Mangalyaan, and TGO are currently orbiting Mars and studying its atmosphere.
