Climate change and aspects of earth system

2. Parts of the Earth System
Air Water Life Land Ice
• The atmosphere (air) extends from the Earth surface for several hundred km.
• The hydrosphere (water) includes the ocean, rivers, lakes, groundwater, vapor.
• The biosphere (life) includes bacteria, plants, and animals.
• The geosphere (land) includes minerals, rocks, molten rock, sediments, soils.
• The cryosphere (ice) includes snow, glaciers, and sea ice.

3. Earth System is designed to act in a conjoined manner. The
Elements that we can think off are all inter-connected! The
Earth System interacts with the Atmosphere in the following
ways:

4. The Earth System interacts with the Biosphere in the following
ways:

5. The Earth System interacts with the Hydrosphere in the following
ways:

6. The Earth System interacts with the Geosphere in the following
ways:

7. The Earth System interacts with Cryosphere in the following ways:

8. Earth system science is the study of how scientific
data stemming from various fields of research, such
as the atmosphere, oceans, land ice and others, fit
together to form the current picture of our planet
as a whole, including its changing climate.
Climate scientists separate factors that affect
climate change into three categories: forcings,
feedbacks, and tipping points.
Forcings: The initial drivers of climate.
 Solar Irradiance: Solar radiation is the source of heat for planet Earth. Scientists also
use evidence from proxy measurements, such as sunspot counts going back centuries
and ancient tree rings, to measure the amount of Sun that reaches Earth’s surface. The
Sun has an 11-year sunspot cycle, which causes about 0.1% of the variation in the
Sun’s output The solar cycle is incorporated into climate models.

9.  Greenhouse gas emissions: Since the industrial
revolution, concentrations of greenhouse gases such
as carbon dioxide (CO2), methane (CH4), and
nitrous oxide (N2O) have risen in the atmosphere.
Burning fossil fuels such as coal, oil and gas has
increased the concentration of atmospheric carbon
dioxide (CO2) from 280 parts per million to 393
parts per million. These greenhouse gases absorb
and then re-radiate heat in Earth’s atmosphere,
which causes increased warming.
 Aerosols, dust, smoke, and soot: Very small airborne particles come from both
human and natural sources and have various effects on climate. Sulfate aerosols,
which result from burning coal, biomass, and volcanic eruptions, tend to cool the
Earth. Other kinds of particles such as black carbon have a warming effect. The
global distribution of aerosols is being tracked from the ground and from satellites.
Total Greenhouse gas emission of Bangladesh

10. Climate feedbacks: processes that can either amplify or diminish the effects of climate
forcings. A feedback that increases an initial warming is called a "positive feedback." A
feedback that reduces an initial warming is a "negative feedback."
 Clouds: Clouds have an enormous impact on Earth's
climate, reflecting about one-third of the total
amount of sunlight that hits the Earth's atmosphere
back into space. Even small changes in cloud
amount, location and type could have large
consequences. A warmer climate could cause more
water to be held in the atmosphere, leading to an
increase in cloudiness and altering the amount of
sunlight that reaches the surface of the Earth. Less
heat would get absorbed, which could slow the
increased warming.
 Precipitation: Global climate models show that
precipitation will generally increase due to the
increased amount of water held in a warmer
atmosphere, but not in all regions. Some regions will
dry out instead. Changes in precipitation patterns, such
as increased water availability, may cause an increase
in plant growth, which in turn could potentially remove
more carbon dioxide from the atmosphere.

11.  Greening of the forests: Natural processes, such as
tree growth, remove about half of human carbon
dioxide emissions from the atmosphere every year.
Scientists are currently studying where this carbon
dioxide goes. The delicate balance between the
absorption and release of carbon dioxide by the
oceans and the world’s great forested regions is the
subject of research by many scientists. There is some
evidence that the ability of the oceans or forests to
continue absorbing carbon dioxide may decline as the
world warms, leading to faster accumulation in the
atmosphere.
 Ice albedo: Ice is white and very reflective, in
contrast to the ocean surface, which is dark and
absorbs heat faster. As the atmosphere warms
and sea ice melts, the darker ocean absorbs more
heat, causes more ice to melt, and makes the
Earth warmer overall. The ice-albedo feedback is
a very strong positive feedback.

12. Climate tipping points: When Earth’s climate abruptly moves between relatively stable
states
 Ocean circulation: As Arctic sea ice and the
Greenland ice sheet melt, ocean circulation in
the Atlantic may divert the Gulf Stream. This
and/or other changes would significantly
change regional weather patterns. A change in
the Gulf Stream could lead to a significant
cooling in Western Europe. This highlights the
importance of ocean circulation in maintaining
regional climates.
 Ice loss: Due to the strong positive feedback of the
ice albedo, if enough ice melts, causing Earth’s
surface to absorb more and more heat, then we
may hit a point of no return. Shrinking ice sheets
contribute to sea level rise. Many hundreds of
millions of people live near a coast, so our ability to
predict sea level rise over the next century has
substantial human and economic ramifications.

13.  Rapid release of methane: Deposits of frozen methane, a potent greenhouse gas,
and carbon dioxide lie beneath permafrost in Arctic regions. About a quarter of the
Northern hemisphere is covered by permafrost. As the environment warms and the
permafrost thaws, these deposits can be released into the atmosphere and present
a risk of enhanced warming.
Gas-hydrate deposits by sectorPotential Methane release in the Eastern
Siberian Arctic Shelf

14. We’ll focuses more on the cycles of the Earth system in which
elements of the living and nonliving parts are discussed.
We will expand the idea;
• The water cycle
• The carbon cycle

15.  What is Water Cycle?
“The water cycle is the path that all water follows as it moves around
Earth in different states. Liquid water is found in oceans, rivers, lakes
and even underground. The water cycle is the path that all water
follows as it moves around our planet.”
“The water cycle is called the hydrologic
cycle. In the hydrologic cycle, water from
oceans, lakes, swamps, rivers, plants, and
even you, can turn into water vapor.
Water vapor condenses into millions of
tiny droplets that form clouds. Clouds
lose their water as rain or snow, which is
called precipitation.”

16. Important of The Water Cycle :
The hydrologic cycle is important because it is how water reaches
plants, animals and us! Besides providing people, animals and plants
with water, it also moves things like nutrients, pathogens and
sediment in and out of aquatic ecosystems.
Movement and Storage of Water
The water cycle includes…
•Water at the surface
•Water underground
•Water vapor in the atmosphere
•Snow and ice – although often considered to be the cryosphere,
snow and ice are also part of the water cycle.

17. Components of the water cycle:
• Atmosphere
• Condensation
• Evaporation
• Evapotranspiration
• Freshwater lakes and rivers
• Groundwater flow
• Groundwater storage
• Ice and snow
• Infiltration
• Oceans
• Precipitation
• Snowmelt
• Springs
• Streamflow
• Sublimation
• Surface runoff

18. Precipitation is a vital component of how water
moves through Earth’s water cycle, connecting
the ocean, land, and atmosphere. Knowing
where it rains, how much it rains and the
character of the falling rain, snow or hail allows
scientists to better understand precipitation’s
impact on streams, rivers, surface runoff and
groundwater. Frequent and detailed
measurements help scientists make models of
and determine changes in Earth’s water cycle.
The water cycle describes how water evaporates from the surface of the earth, rises into
the atmosphere, cools and condenses into rain or snow in clouds, and falls again to the
surface as precipitation. The water falling on land collects in rivers and lakes, soil, and
porous layers of rock, and much of it flows back into the oceans, where it will once more
evaporate. The cycling of water in and out of the atmosphere is a significant aspect of
the weather patterns on Earth.

19. Warming causes increased rate of
evaporation which causes warming.
•Warming climate leads to an increased
evaporation rate.
•More water vapor in the atmosphere.
•Water vapor is a greenhouse gas so
causes even more warming.
The effect of clouds on climate is complicated…
How clouds will affect climate depends on;
•Whether the amount of clouds changes as
climate changes.
•How proportions of cloud types change as
climate changes.
•Whether clouds become higher or lower in the
atmosphere.
Warming clouds : High
cirrus clouds keep sunlight
from radiating away from
Earth into space.
Cooling clouds : Low level
clouds block sunlight from
getting to Earth’s surface.

20. Projected Precipitation Change by 2100
 Blue/green: wetter
 Yellow/red: drier
 Top image - precipitation change during
December, January, and February.
 Bottom - precipitation change during June,
July, and August.
Where will there be MORE precipitation?
Relatively Cool Period:December, January, and
February
Blue/green: wetter, Yellow/red: drier
Relatively Warm Period: June, July, and August
Where will there be LESS precipitation?
Relatively Cool Period: December, January, and
February
Blue/green: wetter ,Yellow/red: drier
Relatively Warm Period: June, July, and August

21. What is the Carbon Cycle?
“The carbon cycle is the process in which carbon travels from the
atmosphere into organisms and the Earth and then back into the
atmosphere. Plants take carbon dioxide from the air and use it to
make food. Animals then eat the food and carbon is stored in their
bodies or released as CO2 through respiration.”
Movement and storage of carbon (C)
through the atmosphere, hydrosphere,
and biosphere of the Earth system
The carbon cycle is often divided into;
(a) “fast carbon cycle”
(b) “slow carbon cycle”.

22.  Greenhouse gases
 Carbon dioxide (CO2)
 Released from burning fossil fuels,
from respiration, and volcanoes
 Taken out of the atmosphere by
plants during photosynthesis
 Methane (CH4)
 Released from farm animals,
manure, landfills, and part of
natural gas deposits
 Methane is about 25 times more
powerful a greenhouse gas than
CO2
 Used as an energy source: burning it
releases CO2

23. The “fast carbon cycle” includes primarily carbon moving
between the atmosphere, biosphere, and hydrosphere.
However, most carbon is in deep storage (as limestone, coal, oil,
and gas) moving through the Earth system on long timescales – the
“slow carbon cycle”.
Today, burning fossil fuels releases deep storage carbon into
the “fast carbon cycle”.

24. Recent Changes in the Carbon Cycle: Carbon Dioxide in the Atmosphere
Recent Changes to the Carbon Cycle
 Forests act as carbon sinks, taking
carbon out of the atmosphere via
photosynthesis.
 In Brazil, a population boom is created
by inexpensive land for farming caused
land use change.
Deforestation

25. Carbon dioxide, dissolved into the
ocean, forms carbonic acid,
lowering the pH of seawater.
Since the start of the Industrial
Revolution, pH of seawater has
dropped about 0.1. In the next
century it is expected to drop
another 0.1-0.35.
More acidic waters make it
difficult for marine life such as
corals to build their CaCO3
skeletons.
This can impact marine ecosystems.
NOAA sensor collecting data about ocean
acidification in coral reef environments. Image:
Bernadette Charpentier

26. The oceans modulate Earth's climate,
influencing crop production on the
continents, the health of fisheries, and
ultimately the quality of life on the planet.
The oceans regulate climate in part by
absorbing and storing carbon dioxide, a
greenhouse gas. Gas exchange between
the atmosphere and the oceans removes
carbon dioxide (CO2) and sequesters
some of it for long periods of time in the
deep sea. The oceans are thought to have
absorbed 30 to 50% of the CO2
produced by the dramatic increase in
burning fossil fuels since the beginning of
the industrial era 200 years ago. Without
this process, CO2 levels in the atmosphere
would be much higher.
Some carbon at the ocean surface is utilized
by phytoplankton and zooplankton to make
calcium carbonate shells or is consumed and
then ejected as fecal pellets that fall and are
buried on the seafloor. This so-called
"biological pump" helps transport carbon
from the ocean surface to the deep ocean.