1 Review Why is the ozone layer important to living things Explain What are the major types of physical and biological evidence for climate change Propose a Solution Suggest one solution for the fisheries problem. Your solution can be at the international, national, regional, or individual level. Explain how it would help, and what challenges you see in implementing it. 2 Interdependence Refer back to the carbon cycle. Describe how extensive burning of fossil fuels is affection other reservoirs of carbon in the atmosphere.

Ch 6 Humans in the Biosphere 6.4 Meeting Ecological Challenges

Ecological Footprint Total area of land and water needed both to provide the resources and to absorb the wastes Used to estimate the biosphere’s carrying capacity.

Footprint Limitations Calculating actual numbers for ecological footprints is complicated There is no universally accepted way to calculate footprint size Footprint in America is almost twice that in England, more than twice that in Japan, and almost six times that in China.

Ecological Footprint

North Atlantic Fisheries From 1950 to 1997, the annual world seafood catch grew from 19 million tons to more than 90 million tons due to larger boats and fish finding electronics Recent dramatic declines in commercial fish populations showed the fish supply is not an endless.

North Atlantic Fisheries

Researching the Cause: Overfishing Gathered data including age structure and growth rates Analysis of these data showed that fish populations were shrinking Fish were being caught faster than they could be replaced by reproduction.

Changing Behavior: Regulation of Fisheries U.S. National Marine Fisheries Service created guidelines for commercial fishing 1996- Sustainable Fisheries Act closed certain areas to fishing until stocks recover and others seasonally to breed and spawn.

Changing Behavior: Regulation of Fisheries Aquaculture Farming of aquatic animals Progress in restoring fish populations has been slow Regulations only apply to territorial waters.

Climate Change Global Warming Increase in average temperature.

Physical Evidence: Changes in Sea Ice and Changes in Sea Level

Biological Evidence Ranges (habitat) of organisms changing Hibernation length is shorter.

Researching the Cause: Models and Questions

How Much Change? Results of models predict the average global temperatures will rise between 2°C to as much as 6.4°C by the end of the twenty-first century.

Changing Behavior: The Challenges Ahead Nations of the world have begun holding international climate summits, at which they attempt to work out agreements to protect the atmosphere and climate.