Environmental Engineering Reference
In-Depth Information
SOME CLIMATE CHANGES AND IMPACTS OF NEXT FEW DECADES AND CENTURIES
FOR 1-4°C WARMING
RAIN
• 5-10% less rainfall
per degree
in Mediterranean, SW North America, southern Africa dry seasons
• 5-10% more rainfall
per degree
in Alaska and other high latitude NH areas
• 3-10% more heavy rain
per degree
in most land areas
RIVERS
• 5-10% less streamflow
per degree
in some river basins, including the Arkansas and Rio Grande
FOOD
• 5-15% reduced yield of US corn, African corn, and Indian wheat
per degree
SEA ICE
• 15% and 25% reductions in Arctic sea ice area
per degree
, in the annual average and September (respectively)
FOR 1-2°C WARMING
FIRE
• 200-400% increase in area burned
per degree
in parts of western US
FOR 3°C
COASTS
• Loss of about 250,000 square km of wetlands and drylands
• Many millions more people at risk of coastal flooding
EXTREMES
• About 9 out of 10 summer seasons expected to be warmer than all but
1 summer out of 20 in the last decades of the 20
th
century over
nearly all land areas
FOR 4°C
EXTREMES
• About 9 out of10 summers warmer than the warmest ever
experienced during the last decades of the 20
th
century over
nearly all land areas
FOR 5°C
FOOD
• Yield losses in most regions and
potential doubling of global grain
prices
1600
1400
Transient
Warming
Equilibrium
Warming
1200
1000
800
AND DA
M
AGE TO CORALS
AND SHELL-FORMING MARINE LIFE
DUE TO INCREASED ACIDITY AND WARMING
600
Stabilization
400
0
1
2
3
4
5
6
7
8
Global Average Warming (°C)
FIGURE Syn.3 What impacts can be expected? The report quantifies—per degree of warming—several
anticipated effects and impacts of global warming, including changes in streamflow, wildfires, crop produc-
tivity, extreme hot summers, and sea level rise. The graphical part of the diagram shows how atmospheric
concentrations of carbon dioxide correspond to temperatures—transient, or near-term warming (in blue),
is only a fraction of the total warming (the equilibrium warming) expected to occur (in red).
