Download Module 7-section2* 50 points

Module 7-section2*
50 points
Potential Climate Impacts
By CA-07 Class
* Module 7 - section1 is the sources of global temperature measurements
section that I did in the class.
Global Warming
• Temperature of the Earth Increasing!
• Global Warming is not Uniform.
• Why?
Ice-Albedeo Feedback
• Ice-Albedo feedback : high latitude warmer
than the low latitude (3-5 0C)
• However, permafrost is just a little bit
different.
• Permafrost = frozen soil.
• When it melts, it becomes an active zone.
• The water and heat from these active zones
can become so strong that it could make holes
in frozen lakes, causing more global warming.
Green house gases
• Warming is more intense in cold parts of
earths surface
• Land is hotter than water because water
evaporates and carries heat away
• Green house heat waves are very intense. In
Europe 2003, 35k people were killed.
Emergent Effects
• Changes in global temp. rearranges weather
patterns and water supply
• A warmer world would increase rainfall, buy
would not be efficiently distributed.
Hadley Circulation
• The equator heats up causing water vapor to
rise and form rain clouds
• As the water vapor warms it causes rainfall at
the equator and drought in the subtropics (30
degrees North or South)
Higher latitude storms
• Global warming will cause the ice sheets to
melt pushing massive amounts of water vapor
into the air.
• The increase in temp will create massive
storms due to the high temp and water vapor
being pushed into the air.
Monsoons
• Monsoons are driven by temperature
difference
• Different temperatures drive the winds to
blow in different ways that dump the water as
rainfall.
• Monsoons are sensitive to change in
temperature that drive them and make them
stronger that tend to vary year to year.
Droughts
• Continental interiors are expected to dry out.
• Areas on earth that are dry today, are expected to
get drier; increasing likelihood of drought.
• Droughts are driven by changes in the water
cycle.
• Drought is probably a more significant danger to
agriculture than heat alone.
• American southwest, Mediterranean, and
Australia are already undergoing drought
conditions.
Plants Transpiration
• Transpiration is essentially evaporation of
water from plants leaves.
• Water is necessary for plants, but only small
amount, which is taken up by the roots is used
for growth and metabolism.
Glaciers
• Are melting during summer, this increases the
sea level.
• Creates social problems- water supply.
Water Vapor
•
•
•
•
Warmer air equals more water vapor
More water vapor equals more energy
More energy equals more rain
Stronger storms as a result of this
Tropical cyclones
• Hurricanes may get more intense and prevalent
in a warmer world.( a warmer world would be
stormier)
• Every year there are about 90 tropical storms, 40
of them become cyclones.
• Storms grow from combinations of winds and
pressures which is serve as seeds for storm.
• The seeds of storm are determined by the
structure of winds in the air, whether they blow
in the same directions or in different directions at
different altitudes.
Hurricanes
• Hurricanes draw their power from water vapor
and warm air over oceans
• They will not form if the Surface Sea Temperature
is below 26 degrees Celsius
• Their birth and growth is affected by subtleties in
the atmosphere and oceans
• A warmer world would lead to more frequent
and more powerful hurricanes
• Cyclones gain power from high winds drawing
cold water from the ocean and warm air together
Storm surge
• Storm surge equals a rise in sea level
• Low pressure in the center of the storm pulls
water up
• Winds blow water up in a pile
• New Orleans was flooded because of this
Ice and Sea Level
• Why does the sea level rise?
-Thermal expansion: when water gets
warmer it expands
- Land ice melting (sea ice, glaciers, mice
sheets, ice shelves)
Ice and Sea Level
• Archimedes’ Principle- ice already in sea does
not raise sea levels, it displaces its own weight
in the water. Ice on land increases sea levels
• Greenland and Antarctica ice sheets hold most
of the water.
• Mountain glaciers respond quickly to climate
• Greenland Ice sheets-air at the base is close to
melting temp. if 2 Celsius warmer, would raise
sea level by 7 m
Ice and Sea Level (cont)
• IPCC forecast sea level to rise from 0.1 to .5m
by end of the century
• It would take thousands of years to melt
Antarctica and Greenland
• Scientists still are not fully sure on all the
factors that cause ice to melt
Ice and Sea Level (cont)
• Sea level depends on the total volume of water in the
ocean
• Also depends on geological movement
• As a result of melting ice sheets
• Isostasy- the earths crust floats on the mantle
• Subtract the melted ice weight & crust will float higher
• Vertical motion in other parts of the world
• Rise in vertical motion
• Bangladesh is being swept away
Human Impacts
• Warming climate due to changes in water
availablility
• Climate changes affect crop yeilds because
corn is sensitive to heat spikes
– Less corn per season
• Increasing CO2 helps plants deal with water
stress
• Farmers will have to plant different crops in
the future
Human Impacts
• Number of species on Earth is decreasing due
to human land use
• Climate change contributes to extinction
because it forces natural ecosystems to
relocate
• This is due to human land use and
industrializing their habitats
Human impact
• Rising temperatures are widening the areas
that tropical diseases are able to effect
• Tropical disease has a significant impact but is
not the most important reason to combat
global warming
• The impact of global warming is more likely to
effect tropical and third world countries where
there are less resources to buffer set backs.
HW-6: Due Oct 29th
1) Explain briefly why Global warming is not
globally uniform (Include 5 factors in your
discussion).
2) What is the role of vegetation in a drought?
3) Why do some kinds of ice on Earth change
the sea level when they melt and other kinds
do not?