e16.    What do computer models of greenhouse changes show?

Global warming could cause the mean temperatures to rise 1.5^o-5.5^oC by 2050. Northern Hemisphere could warm more and sooner because of the concentration of landmass. Temperatures at middle and high latitudes could increase 2 to 3 times faster than the global average. Soil could be drier in the middle latitudes in the Northern Hemisphere and more areas could have forest fires, brush fires, and heat waves. Average sea level could rise 2 to 4 cm per decade. Air pollution from volcanoes and burning fossil fuels may put sufficient particles into the atmosphere to keep heat out. Extra CO₂ may cause photosynthesis to speed up; however, if the land has been cleared, there may be still be very few food crops that can sustain civilizations because of the rinsing population. Arctic tundra, if it thaws, could release more methane into the atmosphere, increasing global warming. These changes will effect food production. Water is the limiting factor; plant-growing areas would shift northward at a rate of 150 meters per 1^oC rise. Forests move toward the poles IF they can keep up with the rate of change, typically 0.9 km per year. See Figure 07. Climate Zones for current conditions in the United States.

g01.    What was the second atmosphere like?

g02.    What was the primitive atmosphere like?

g03.    How did the atmosphere change after the Precambrian?

g08.    What are the spheres that make up the earth?

g13.    What makes up earth's climate?

g19.    Where do you find air pollution?

m07.    Why is there stress on National Parks?

m18.  To whom are rainforests important?

m21.    Why is there controversy over old-growth deforestation?

m28.    How is biomass used for energy?

m29.    How is oil recovered?

m30.    How is natural gas used?

m34.    How could food production affect the environment?

m36.    How could human health be affected by weather extremes?

m37.    What are some methods to slow global warming?

m35.    How can global warming affect biodiversity?  

m39.    How does ozone affect life?  

m40.    What are some solutions to the problem of disappearing ozone?  

m65.    What can cause biological hazards?