While the debate goes on as to whether there really is a phenomenon called global warming, a number of leading environmental and scientific organizations have come together to map the signs that global warming is already affecting our planet.
A new map showing the early warning signs of global warming has been published as a joint effort of the following organizations: Environmental Defense Fund, Natural Resources Defense Council, Sierra Club, Union of Concerned Scientists, U.S. Public Interest Research Group, Work Resources Institute, and the World Wildlife Fund.
The map marks events that are direct manifestations of the long-term trend toward global warming (the "fingerprints"), and events that foreshadow the types of impacts likely to become more widespread with global warming (the "harbingers"). While the indicators are most heavily concentrated in North America and Europe, they show that the problem is clearly a global one as the climate changes around the world.
Learning about the Problem
Global warming will impact the world in many ways. One impact is an expected change in the geographic distribution of species as average temperatures of their habitats change. This effect will be strongly felt in streams, rivers, and lakes. See the activity Biology Explorer: Global Warming to see how a rise in water temperature may affect two species of fish.
Thinking about the Problem
Changes in average temperature can have an impact on all species, including humans. Make a list of some of the ways that extreme temperatures affect humans. Consider food and water supplies, long heat waves or cold spells, diseases, etc.
For the Teacher: Extending the Problem
Global warming will continue to be in the news. There are a significant number of Web sites dealing with the scientific, political, and economic impact of global warming. The following sites have an educational focus:
Students who want to see how global warming affects various animal species can check some of the following articles: