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Water
covers approximately 70% of the earth's surface. But only 3% is potable
(fresh drinking water).
Hydrogen
is the most abundant chemical substance in the universe, constituting
roughly 75 percent of normal matter by mass and more than 90 percent by
number of atoms.
Is this good news?
We
think so. Water is the source of life on planet
earth, without which, humans could not live for more than a few
days. Nor could most wildlife, and flora would not last very much
longer. Even cactus and camels, eventually need water.
WORLD BANK REPORT
A World Bank
report finds that water scarcity, exacerbated by climate
change, could hinder economic growth, spur migration, and
spark conflict. However, most countries can neutralize the adverse
impacts of water scarcity by taking action to allocate and use water
resources more efficiently.
KEY FINDINGS:
- Water scarcity, exacerbated by climate
change, could cost some regions up to 6% of their GDP, spur migration, and spark conflict.
- The combined effects of growing populations, rising
incomes, and expanding cities will see demand for water rising
exponentially, while supply becomes more erratic and uncertain.
- Unless action is taken soon, water will become scarce in
regions where it is currently abundant - such as Central Africa and East
Asia - and scarcity will greatly worsen in regions where water is
already in short supply - such as the Middle East and the Sahel in Africa. These regions could see their growth rates decline by as much as
6% of GDP by 2050 due to water-related impacts on agriculture, health,
and incomes.
- Water insecurity could multiply the risk of conflict. Food
price spikes caused by droughts can inflame latent conflicts and drive
migration. Where economic growth is impacted by rainfall, episodes of
droughts and floods have generated waves of migration and spikes in
violence within countries.
- The negative impacts of climate change on water could be
neutralized with better policy decisions, with some regions standing to
improve their growth rates by up to 6% with better water resource
management.
-
Improved water stewardship pays high economic dividends. When
governments respond to water shortages by boosting efficiency and
allocating even 25% of water to more highly-valued uses, such as more
efficient agricultural practices, losses decline dramatically and for
some regions may even vanish.
- In the world’s extremely dry regions, more far-reaching
policies are needed to avoid inefficient water use. Stronger policies
and reforms are needed to cope with deepening climate stresses.
- Policies and investments that can help lead countries to more water secure and climate-resilient economies include:
* Better planning for water resource allocation
* Adoption of incentives to increase water efficiency, and
* Investments in infrastructure for more secure water supplies and availability.
THE HYDROGEN ECONOMY
Nearly two decades have passed since the US released its Energy
Policy Act of
2005 under President George
Bush. This addressed the hydrogen
economy in the US and triggered a hydrogen boom, beginning in the US and
spreading around the world. Then the 2008 global financial crisis hit;
its fallout created a headache for hydrogen
energy
as significant funding and effort were redirected to more urgent
problems. The hydrogen boom faded away between 2009 and 2010 and many
factors are to blame for this. That the available technology was too
expensive and not mature enough to be applied commercially was another
contributor. Yet, the funding available for research and development of
hydrogen technologies allowed the hydrogen economy to slowly mature in
the following years.
TEN YEARS ON
It took nearly a decade for hydrogen to make a comeback. In that
time, Japan, South Korea and China rapidly emerged as the hydrogen
leaders. In 2017, Japan and South Korea decided to officially support
the hydrogen economy and make it an important part of their energy
security strategies. Meanwhile, Australia began to see renewable
hydrogen and other renewable fuels as a potential new mass export.
The Chinese government sees hydrogen as a viable strategy for
addressing fossil fuel pollution in transportation. It provides many
subsidies, tax incentives and grants to develop hydrogen fuel cell
vehicles and build hydrogen refuelling and energy storage
infrastructure. While big announcements stating that entire countries or
cities can run solely on hydrogen may sound like a dream, the hydrogen
economy is steadily becoming a reality.
Continuous technology development over the last ten years has
allowed the idea of hydrogen-based energy to return stronger than ever.
The Paris Agreement
and announcements made in 2021 by a number of countries to phase out
the use of internal combustion engines in the coming decades further
benefited the hydrogen
economy.
California and Germany already have a number of hydrogen
refuelling stations. Hydrogen
fuel cells can also store surplus energy
produced from renewable resources, such as solar
power, wind
power, or hydropower. Hydrogen finds uses in numerous other industries as well.
Oil and gas and the food industry rely on hydrogen for crude oil and food processing respectively.
COMPETING USES FOR WATER
Producing hydrogen from renewable resources involves the electrolysis
of water, where an electric charge splits water molecules into hydrogen
and oxygen. In an era of increasing water security issues, rapidly
progressing
climate change and droughts, however, water scarcity has become an urgent problem globally. A
growing world population
only worsens the water scarcity problem. Many have questioned whether
using hydrogen for energy storage and transportation fuel will force
industries, such as the energy sector and agriculture, to compete for water resources.
Once hydrogen is combusted with oxygen to release energy, it
becomes water. This in return, opens up a unique opportunity, where
countries with water scarcity could not only import energy, but also
address their water shortages through hydrogen.
DESERT AND ISLAND NATIONS
Only nine of the 135 countries, in a World Economic Forum
study, would require an increase in their current freshwater withdrawal
of over 10% to completely transition to hydrogen-based energy, whereas
62 countries would need to increase their freshwater withdrawal by less
than 1%. There is a visible trend among the countries with a significant
increase in water withdrawal to transition to hydrogen. These countries
are either desert countries with little annual precipitation, such as
Qatar, Israel, Kuwait or Bahrain, or small island states, such as
Singapore, Trinidad and Tobago or Malta, which would also struggle due
to limited freshwater reservoirs.
Singapore, which relies highly on neighbouring Malaysia for
freshwater resources, tops the list. It would have to increase the water
it uses to convert to hydrogen-based energy by about 46.4%. On the
other hand, Tajikistan, being at the very bottom of the list, would
require an increase of only 0.056%. The average value for all 135
countries is 3.3%.
The hydrogen economy also opens up interesting prospects for
countries that are already experiencing water shortages, including
Singapore and Qatar. It is unlikely that these two states will produce
their own hydrogen, they will rely on imported hydrogen. This allows
them to capture water produced from the
re-conversion of hydrogen back into energy, either via combustion or fuel-cell technology, and then reuse this high-purity water locally.
It is clear that the shift to a hydrogen-based economy for most
will not negatively impact water security or other water-heavy
industries. While hydrogen can gain a significant share of the
transportation market, other energy-related sectors will most likely
experience a mix of different technologies, which lowers the percentage
of water used for hydrogen. In addition, when hydrogen is burned or
converted with atmospheric oxygen in the fuel
cell, water is formed,
which can be captured and reused to produce more hydrogen. With more
countries making hydrogen part of their energy agenda, the hydrogen
economy could soon arrive in our households, providing clean, efficient
and carbon-free solutions for transportation, electricity generation,
central heating and even cooking.
CIRCULARITY
It should be remembered that splitting water to obtain hydrogen, then re-combining it with
oxygen in a fuel cell, takes us back to water.
It does not need to be captured, to find its way back into the Water
Cycle.
CHEMISTRY
Water
(chemical formula H2O) is an inorganic, transparent, tasteless,
odorless, and nearly colorless chemical substance, which is the main
constituent of Earth's hydrosphere and the fluids of all known living
organisms (in which it acts as a solvent). It is vital for all known
forms of life, despite providing neither food, energy, nor organic
micronutrients. Its chemical formula, H2O, indicates that each of its
molecules contains one oxygen and two hydrogen atoms, connected by
covalent bonds. The hydrogen atoms are attached to the oxygen atom at an
angle of 104.45°. "Water" is also the name of the liquid state of H2O
at standard temperature and pressure.
WATER CYCLE
The water cycle (known scientifically as the hydrologic cycle)
refers to the continuous exchange of water within the hydrosphere,
between the atmosphere, soil water, surface water, groundwater, and
plants.
Water moves perpetually through each of these regions in the water cycle consisting of the following transfer processes:
- evaporation from oceans and other water bodies into the air
and transpiration from land plants and animals into the air.
- precipitation, from water vapor condensing from the air and falling to the earth or ocean.
- runoff from the land usually reaching the sea.
Most water vapors found mostly in the ocean returns to it, but
winds carry water vapor over land at the same rate as runoff into the
sea, about 47 Tt per year whilst evaporation and transpiration happening
in land masses also contribute another 72 Tt per year. Precipitation,
at a rate of 119 Tt per year over land, has several forms: most commonly
rain, snow, and hail, with some contribution from fog and dew. Dew is
small drops of water that are condensed when a high density of water
vapor meets a cool surface. Dew usually forms in the morning when the
temperature is the lowest, just before sunrise and when the temperature
of the earth's surface starts to increase. Condensed water in the air
may also refract sunlight to produce rainbows.
Water runoff often collects over watersheds flowing into rivers.
Through erosion, runoff shapes the environment creating river valleys
and deltas which provide rich soil and level ground for the
establishment of population centers. A flood occurs when an area of
land, usually low-lying, is covered with water which occurs when a river
overflows its banks or a storm surge happens. On the other hand,
drought is an extended period of months or years when a region notes a
deficiency in its water supply. This occurs when a region receives
consistently below average precipitation either due to its topography or
due to its location in terms of latitude.
SEAWATER & TIDES
Seawater contains about 3.5% sodium chloride on average, plus
smaller amounts of other substances. The physical properties of seawater
differ from fresh water in some important respects. It freezes at a
lower temperature (about −1.9 °C (28.6 °F)) and its density increases
with decreasing temperature to the freezing point, instead of reaching
maximum density at a temperature above freezing. The salinity of water
in major seas varies from about 0.7% in the Baltic Sea to 4.0% in the
Red Sea. (The Dead Sea, known for its ultra-high salinity levels of
between 30 and 40%, is really a salt lake.)
Tides are the cyclic rising and falling of local sea levels
caused by the tidal forces of the Moon and the Sun acting on the oceans.
Tides cause changes in the depth of the marine and estuarine water
bodies and produce oscillating currents known as tidal streams. The
changing tide produced at a given location is the result of the changing
positions of the Moon and Sun relative to the Earth coupled with the
effects of Earth rotation and the local bathymetry. The strip of
seashore that is submerged at high tide and exposed at low tide, the
intertidal zone, is an important ecological product of ocean
tides.
LIFE SUPPORT
From a biological standpoint, water has many distinct properties
that are critical for the proliferation of life. It carries out this
role by allowing organic compounds to react in ways that ultimately
allow replication. All known forms of life depend on water. Water is
vital both as a solvent in which many of the body's solutes dissolve and
as an essential part of many metabolic processes within the body.
Metabolism is the sum total of anabolism and catabolism. In anabolism,
water is removed from molecules (through energy requiring enzymatic
chemical reactions) in order to grow larger molecules (e.g., starches,
triglycerides, and proteins for storage of fuels and information). In
catabolism, water is used to break bonds in order to generate smaller
molecules (e.g., glucose, fatty acids, and amino acids to be used for
fuels for energy use or other purposes). Without water, these particular
metabolic processes could not exist.
Water is fundamental to photosynthesis and respiration.
Photosynthetic cells use the sun's energy to split off water's hydrogen
from oxygen. Hydrogen is combined with CO2 (absorbed from air or water)
to form glucose and release oxygen. All living cells use such fuels and
oxidize the hydrogen and carbon to capture the sun's energy and reform
water and CO2 in the process (cellular respiration).
CIVILIZATIONS
Civilization has historically flourished around rivers and major
waterways; Mesopotamia, the so-called cradle of civilization, was
situated between the major rivers Tigris and Euphrates; the ancient
society of the Egyptians depended entirely upon the
Nile. The early Indus Valley civilization (c. 3300 BCE to
1300 BCE) developed along the Indus River and tributaries that flowed
out of the Himalayas. Rome was also founded on the banks of the Italian
river Tiber. Large metropolises like Rotterdam, London, Montreal, Paris,
New York City, Buenos Aires, Shanghai, Tokyo, Chicago, and Hong Kong
owe their success in part to their easy accessibility via water and the
resultant expansion of trade. Islands with safe water ports, like
Singapore, have flourished for the same reason. In places such as North
Africa and the Middle East, where water is more scarce, access to clean
drinking water was and is a major factor in human development.
HUMAN HEALTH & WASTEWATER POLLUTION
Water fit for human consumption is called drinking water or
potable water. Water that is not potable may be made potable by
filtration or distillation, or by a range of other methods. More than
660 million people do not have access to safe drinking water.
Water that is not fit for drinking but is not harmful to humans
when used for swimming or bathing is called by various names other than
potable or drinking water, and is sometimes called safe water, or "safe
for bathing". Chlorine is a skin and mucous membrane irritant that is
used to make water safe for bathing or drinking. Its use is highly
technical and is usually monitored by government regulations (typically 1
part per million (ppm) for drinking water, and 1–2 ppm of chlorine not
yet reacted with impurities for bathing water). Water for bathing may be
maintained in satisfactory microbiological condition using chemical
disinfectants such as chlorine or ozone or by the use of ultraviolet
light.
Water reclamation is the process of converting wastewater (most
commonly sewage, also called municipal wastewater) into water that can
be reused for other purposes. There are 2.3 billion people who reside in
nations with water scarcities, which means that each individual
receives less than 1 700 m3 of water annually. 380 billion m3 of
municipal wastewater are produced globally each year.
Freshwater is a renewable resource, recirculated by the natural
hydrologic cycle, but pressures over access to it result from the
naturally uneven distribution in space and time, growing economic
demands by agriculture and industry, and rising populations. Currently,
nearly a billion people around the world lack access to safe, affordable
water. In 2000, the United Nations established the Millennium
Development Goals for water to halve by 2015 the proportion of people
worldwide without access to safe water and sanitation. Progress toward
that goal was uneven, and in 2015 the UN committed to the Sustainable
Development Goals of achieving universal access to safe and affordable
water and sanitation by 2030. Poor water quality and bad sanitation are
deadly; some five million deaths a year are caused by water-related
diseases. The World Health Organization estimates that safe water could
prevent 1.4 million child deaths from diarrhoea each year.
In developing countries, 90% of all municipal wastewater still
goes untreated into local rivers and streams. Some 50 countries, with
roughly a third of the world's population, also suffer from medium or
high water scarcity and 17 of these extract more water annually than is
recharged through their natural water cycles. The strain not only
affects surface freshwater bodies like rivers and lakes, but it also
degrades groundwater resources.
AGRICULTURE
The most substantial human use of water is for agriculture,
including irrigated agriculture, which accounts for as much as 80 to 90
percent of total human water
consumption. In the United States, 42% of freshwater withdrawn
for use is for irrigation, but the vast majority of water "consumed"
(used and not returned to the environment) goes to agriculture.
Access to fresh water is often taken for granted, especially in
developed countries that have built sophisticated water systems for
collecting, purifying, and delivering water, and removing wastewater.
But growing economic, demographic, and climatic pressures are increasing
concerns about water issues, leading to increasing competition for
fixed water resources, giving rise to the concept of peak water. As
populations and economies continue to grow, consumption of water-thirsty
meat expands, and new demands rise for biofuels or new water-intensive
industries, new water challenges are likely.
An assessment of water management in agriculture was conducted
in 2007 by the International Water Management Institute in Sri Lanka to
see if the world had sufficient water to provide food for its growing
population. It assessed the current availability of water for
agriculture on a global scale and mapped out locations suffering from
water scarcity. It found that a fifth of the world's people, more than
1.2 billion, live in areas of physical water scarcity, where there is
not enough water to meet all demands. A further 1.6 billion people live
in areas experiencing economic water scarcity, where the lack of
investment in water or insufficient human capacity make it impossible
for authorities to satisfy the demand for water. The report found that
it would be possible to produce the food required in the future, but
that continuation of today's food production and environmental trends
would lead to crises in many parts of the world. To avoid a global water
crisis, farmers will have to strive to increase productivity to meet
growing demands for food, while industries and cities find ways to use
water more efficiently.
Water scarcity is also caused by production of water intensive
products. For example, cotton: 1 kg of
cotton - equivalent of a pair of jeans - requires 10.9 cubic
meters (380 cu ft) water to produce. While cotton accounts for 2.4% of
world water use, the water is consumed in regions that are already at a
risk of water shortage. Significant environmental damage has been
caused: for example, the diversion of water by the former Soviet Union
from the Amu Darya and Syr Darya rivers to produce cotton was largely
responsible for the disappearance of the Aral Sea.
DRINKING WATER
The human body contains from 55% to 78% water, depending on body
size. To function properly, the body requires between one and seven
liters (0.22 and 1.54 imp gal; 0.26 and 1.85 U.S. gal) of water per day
to avoid dehydration; the precise amount depends on the level of
activity, temperature, humidity, and other factors. Most of this is
ingested through foods or beverages other than drinking straight water.
It is not clear how much water intake is needed by healthy people,
though the British Dietetic Association advises that 2.5 liters of total
water daily is the minimum to maintain proper hydration, including 1.8
liters (6 to 7 glasses) obtained directly from beverages. Medical
literature favors a lower consumption, typically 1 liter of water for an
average male, excluding extra requirements due to fluid loss from
exercise or warm weather.
Healthy kidneys can excrete 0.8 to 1 liter of water per hour,
but stress such as exercise can reduce this amount. People can drink far
more water than necessary while exercising, putting them at risk of
water intoxication (hyperhydration), which can be fatal. The popular
claim that "a person should consume eight glasses of water per day"
seems to have no real basis in science. Studies have shown that extra
water intake, especially up to 500 milliliters (18 imp fl oz; 17 U.S. fl
oz) at mealtime was associated with weight loss. Adequate fluid intake
is helpful in preventing constipation.
An original recommendation for water intake in 1945 by the Food
and Nutrition Board of the U.S. National Research Council read: "An
ordinary standard for diverse persons is 1 milliliter for each calorie
of food. Most of this quantity is contained in prepared foods." The
latest dietary reference intake report by the U.S. National Research
Council in general recommended, based on the median total water intake
from US survey data (including food sources): 3.7 liters (0.81 imp gal;
0.98 U.S. gal) for men and 2.7 liters (0.59 imp gal; 0.71 U.S. gal) of
water total for women, noting that water contained in food provided
approximately 19% of total water intake in the survey.
Specifically, pregnant and breastfeeding women need additional
fluids to stay hydrated. The US Institute of Medicine recommends that,
on average, men consume 3 liters (0.66 imp gal; 0.79 U.S. gal) and women
2.2 liters (0.48 imp gal; 0.58 U.S. gal); pregnant women should
increase intake to 2.4 liters (0.53 imp gal; 0.63 U.S. gal) and
breastfeeding women should get 3 liters (12 cups), since an especially
large amount of fluid is lost during nursing. Also noted is that
normally, about 20% of water intake comes from food, while the rest
comes from drinking water and beverages (caffeinated included). Water is
excreted from the body in multiple forms; through urine and feces,
through sweating, and by exhalation of water vapor in the breath. With
physical exertion and heat exposure, water loss will increase and daily
fluid needs may increase as well.
Humans require water with few impurities. Common impurities include metal salts and oxides, including
copper,
iron,
calcium
and
lead, and/or harmful bacteria, such as Vibrio. Some solutes are
acceptable and even desirable for taste enhancement and to provide
needed electrolytes.
THE WATER SUPPLY & TREATMENT INDUSTRY
The water industry provides drinking water and wastewater
services (including sewage treatment) to households and industry. Water
supply facilities include water wells, cisterns for rainwater
harvesting, water supply networks, and water purification facilities,
water tanks, water towers, water pipes including old aqueducts.
Atmospheric water generators are in development.
Drinking water is often collected at springs, extracted from
artificial borings (wells) in the ground, or pumped from lakes and
rivers. Building more wells in adequate places is thus a possible way to
produce more water, assuming the aquifers can supply an adequate flow.
Other water sources include rainwater collection. Water may require
purification for human consumption. This may involve the removal of
undissolved substances, dissolved substances and harmful microbes.
Popular methods are filtering with sand which only removes undissolved
material, while chlorination and boiling kill harmful microbes.
Distillation does all three functions. More advanced techniques exist,
such as reverse osmosis. Desalination of abundant seawater is a more
expensive solution used in coastal arid climates.
The distribution of drinking water is done through municipal
water systems, tanker delivery or as bottled water. Governments in many
countries have programs to distribute water to the needy at no charge.
Reducing usage by using drinking (potable) water only for human
consumption is another option. In some cities such as Hong Kong,
seawater is extensively used for flushing toilets citywide in order to
conserve freshwater resources.
Polluting water may be the biggest single misuse of water; to
the extent that a pollutant limits other uses of the water, it becomes a
waste of the resource, regardless of benefits to the polluter. Like
other types of pollution, this does not enter standard accounting of
market costs, being conceived as externalities for which the market
cannot account. Thus other people pay the price of water pollution,
while the private firms' profits are not redistributed to the local
population, victims of this pollution. Pharmaceuticals consumed by
humans often end up in the waterways and can have detrimental effects on
aquatic life if they
bioaccumulate and if they are not biodegradable.
Municipal and industrial wastewater are typically treated at
wastewater treatment plants. Mitigation of polluted surface runoff is
addressed through a variety of prevention and treatment techniques.
POLITICS
Water politics is politics affected by water and water
resources. For this reason, water is a strategic resource in the globe
and an important element in many political conflicts. It causes health
impacts and damage to biodiversity.
Access to safe drinking water has improved over the last decades
in almost every part of the world, but approximately one billion people
still lack access to safe water and over 2.5 billion lack access to
adequate sanitation. However, some observers have estimated that by 2025
more than half of the world population will be facing water-based
vulnerability. A report, issued in November 2009, suggests that by 2030,
in some developing regions of the world, water demand will exceed
supply by 50%.
1.6 billion people have gained access to a safe water source
since 1990. The proportion of people in developing countries with access
to safe water is calculated to have improved from 30% in
1970 to 71% in 1990, 79% in 2000 and 84% in 2004.
A 2006 United Nations report stated that "there is enough water
for everyone", but that access to it is hampered by mismanagement and
corruption. In addition, global initiatives to improve the efficiency of
aid delivery, such as the Paris Declaration on Aid Effectiveness, have
not been taken up by water sector donors as effectively as they have in
education and health, potentially leaving multiple donors working on
overlapping projects and recipient governments without empowerment to
act.
The authors of the 2007 Comprehensive Assessment of Water
Management in Agriculture cited poor governance as one reason for some
forms of water scarcity. Water governance is the set of formal and
informal processes through which decisions related to water management
are made. Good water governance is primarily about knowing what
processes work best in a particular physical and socioeconomic context.
Mistakes have sometimes been made by trying to apply 'blueprints' that
work in the developed world to developing world locations and contexts.
The Mekong river is one example; a review by the International Water
Management Institute of policies in six countries that rely on the
Mekong river for water found that thorough and transparent cost-benefit
analyses and environmental impact assessments were rarely undertaken.
They also discovered that Cambodia's draft water law was much more
complex than it needed to be.
The UN World Water Development Report (WWDR, 2003) from the
World Water Assessment Program indicates that, in the next 20 years, the
quantity of water available to everyone is predicted to decrease by
30%. 40% of the world's inhabitants currently have insufficient fresh water for minimal
hygiene. More than 2.2 million people died in 2000 from
waterborne diseases (related to the consumption of contaminated water)
or drought. In 2004, the UK charity WaterAid reported that a child dies
every 15 seconds from easily preventable water-related diseases; often
this means lack of sewage disposal.
Organizations concerned with water protection include the
International Water Association (IWA), WaterAid, Water 1st, and the
American Water Resources Association. The International Water Management
Institute undertakes projects with the aim of using effective water
management to reduce poverty. Water related conventions are United
Nations Convention to Combat Desertification (UNCCD), International
Convention for the Prevention of Pollution from Ships,
United Nations Convention on the Law of the Sea
(UNCLOS)
and Ramsar Convention. World Day for Water takes place on 22 March and World Oceans Day on 8 June.
PLASTIC POLLUTION - MARINE LITTER
Marine
Litter in the oceans continues to accumulate, without very
much in the way of intervention. One study reveals that at the present
rate, there will be more plastic in the sea than fish by 2050. Plastic
attracts toxins, making it an
unattractive bio-accumulative carcinogenic proliferation, in the
present
circumstances.
WATER IN SPACE
Much of the universe's water is produced as a byproduct of star
formation. The formation of stars is accompanied by a strong outward
wind of gas and dust. When this outflow of material eventually impacts
the surrounding gas, the shock waves that are created compress and heat
the gas. The water observed is quickly produced in this warm dense gas.
On 22 July 2011, a report described the discovery of a gigantic
cloud of water vapor containing "140 trillion times more water than all
of Earth's oceans combined" around a quasar located 12 billion light
years from Earth. According to the researchers, the "discovery shows
that water has been prevalent in the universe for nearly its entire
existence".
Water has been detected in interstellar clouds within the Milky
Way. Water probably exists in abundance in other galaxies, too, because
its components, hydrogen, and oxygen, are among the most abundant
elements in the universe. Based on models of the formation and evolution
of the Solar System and that of other star systems, most other
planetary systems are likely to have similar ingredients
The Earth is located in the habitable zone of the Solar
System; if it were slightly closer to or farther from the
Sun (about 5%, or about 8 million kilometers), the conditions which
allow the three forms to be present simultaneously would be far less
likely to exist. We are lucky SOBs. We should not muck it up.
Earth's gravity allows it to hold an atmosphere. Water vapor and
carbon dioxide in the atmosphere provide a temperature buffer
(greenhouse effect) which helps maintain a relatively steady surface
temperature. If Earth were smaller, a thinner atmosphere would allow
temperature extremes, thus preventing the accumulation of water except
in polar ice caps (as on Mars).
The surface temperature of Earth has been relatively constant
through geologic time despite varying levels of incoming solar radiation
(insolation), indicating that a dynamic process governs Earth's
temperature via a combination of greenhouse gases and surface or
atmospheric albedo. This proposal is known as the Gaia
hypothesis.
The state of water on a planet depends on ambient pressure,
which is determined by the planet's gravity. If a planet is sufficiently
massive, the water on it may be solid even at high temperatures,
because of the high pressure caused by gravity, as it was observed on
exoplanets Gliese 436 b and GJ 1214 b.
AQUARIANS
- ASTROLOGY
Aquarians
have the star sign dates between January 21st and February 19th, and
belong to the Air element of the zodiac (along with Gemini and Libra -
who they have the most romantic compatibility with, FYI). Aquarians are
ruled by Uranus, which is the planet of invention, innovation, space
travel and aerodynamics. Aquarians not only want to save the world, but
they’ve got the engineering and intellectual smarts to actually have a
plan on how to do it too.
Aquarius’s symbol is the water bearer, which many believe
represents the gifts of truth and pure intentions that they bring to the
world. Aquarians are very upfront people, and they don’t do shenanigans
or shady business. They’ll tell you how it is and feel no two ways
about it if you don’t like it. Some people find them aloof or cold, but
they just keep their emotions more buttoned down than most.
The world is their oyster. They care what happens on our planet
(and beyond). There is a deep sense of justice, liberalness and fairness
in all Aquarians. They just don't "do" petty shit. This leads them,
more often than not, into alternative lifestyles, campaigning, charity
and green politics.
AQUANAUTS
n
aquanaut is any person who remains underwater, breathing at the ambient
pressure for long enough for the concentration of the inert components
of the breathing gas dissolved in the body tissues to reach equilibrium,
in a state known as saturation. Usually this is done in an underwater
habitat on the seafloor for a period equal to or greater than 24
continuous hours without returning to the surface. The term is often
restricted to scientists and academics, though there were a group of
military aquanauts during the SEALAB program. Commercial divers in
similar circumstances are referred to as saturation divers. An aquanaut
is distinct from a submariner, in that a submariner is confined to a
moving underwater vehicle such as a
submarine
that holds the water pressure out. Aquanaut derives from the Latin word
aqua ("water") plus the Greek nautes ("sailor"), by analogy to the
similar construction "astronaut".
The first human aquanaut was Robert Sténuit, who spent 24 hours
on board a tiny one-man cylinder at 200 feet (61 m) in September 1962
off Villefranche-sur-Mer on the French Riviera. Military aquanauts
include Robert Sheats, author Robin Cook, and astronauts Scott Carpenter
and Alan Shepard. Civilian aquanaut Berry L. Cannon died of carbon
dioxide poisoning during the U.S. Navy's SEALAB III project. Scientific
aquanauts include Sylvia Earle, Jonathan Helfgott, Joseph B. MacInnis,
Dick Rutkowski, Phil Nuytten, and about 700 others, including the crew
members (many of them astronauts) of NASA's NEEMO missions at the
Aquarius underwater laboratory.
In
fiction, Captain
Nemo and his crew were aquanauts, in 20,000
Leagues Under the Sea.
LINKS
https://www.worldbank.org/en/topic/water/publication/high-and-dry-climate-change-water-and-the-economy
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