If global warming is a reality, as most now agree it is, then its consequences must be considered. The possible consequences of global warming are controversial and difficult to predict. However, most of the scientists who study the atmosphere agree that the following are likely results of increased global warming, although the extent to which each of these phenomena may manifest itself is debatable.
- Oceans may warm and release more carbon dioxide due to the reduced solubility of gases in warm water. This would increase warming even more and exacerbate the problem. However, warmer oceans might allow more phytoplankton to grow, which could consume more carbon dioxide.
- Solid, frozen methane deposits at the bottom of the oceans may become gaseous as the ocean warms, and the gaseous methane would be released into air. This would increase warming even more.
- Ice and snow cover may decrease significantly in parts of the world. This would cut down on reflected light so Earth would absorb even more radiation and warm up at an accelerated rate.
- Ocean levels may rise as ice and snow at the polar caps melt. The consequences for islands and low-lying areas along coasts could be disastrous. There is already evidence of this occurring. Ice shelves that have been frozen for thousands of years are breaking away. The Arctic Climate Impact Assessment, a study by over 300 scientists released in late 2004, suggested that, among other consequences of such warming, polar bears could become extinct by 2099.
- More water might evaporate from the oceans as they warm. This could increase global warming because water is a greenhouse gas. However, this could be offset by the reflective effect that additional cloud cover might have on incoming solar radiation.
- Warming of the oceans could cause major shifts in ocean currents, leading to unpredictable influences on weather, fisheries, etc.
- Rainfalls would become much heavier in some areas as a result of increased evaporation. This would lead to increased flooding.
- The tree line would move farther north, causing trees to grow over a broader region. This could consume more carbon dioxide.
- Deserts and arable regions of the world could shift location and change size as a function of shifts in areas of rainfall. The consequences are difficult to predict.
- Tropical diseases might become more prevalent and widespread as Earth warms.
- The intensity of storms and weather systems would probably increase.
- Increased heat may mean worsened air pollution, damaged crops, and depleted resources in some areas.
- Some scientists have speculated that when a certain atmospheric concentration of greenhouse gases is reached, it may trigger a relatively rapid and cataclysmic climate system reorganization.
- Possibly, nothing of consequence, that is, nothing we can’t handle, will happen.
Excerpted from the book
Joesten, M., et al. The World of Chemistry Essentials, 4th edition, Thomson, Brooks/Cole, 2007.
