Global warming and its effects on endangered species
Greenhouse gases (GHGs), such as carbon dioxide and nitrous oxides, occur naturally in our atmosphere to
trap some of the sun's heat and warm our earth, keeping it at the hospitable average 60°F we are accustomed to.
Without these gases, life as we know it could not exist; the temperatures would be far below freezing. However,
the other extreme can happen as well. If there are too many GHGs in the atmosphere, the earth gets hotter,
adversely affecting many species (EPA 2001).
Since the turn of the century, global mean temperatures have risen about 1°F. Since the beginning of the industrial revolution, the atmospheric concentrations of carbon dioxide has increased 30%, methane concentrations have doubled, and nitrous oxide concentrations have increased 15% (EPA 2001). Coincidence? Unlikely.
If GHG emissions continue to increase as they have, by 2100 global mean temperatures will rise another
2 to 10°F. What does this mean to us? To our species? A lot. As the earth warms, sea levels will rise (they
already have risen four to eight inches). Among other things, this might cause the spread of water-borne
diseases and the loss of crucial coastal habitats. Specifically, estuarine beaches, relied upon by endangered
species such as the least tern (Sterna antillarum), will likely be destroyed; many shore birds rely on these
beaches for food specific to these locations, such as horseshoe crabs. It is uncertain what will happen when
this food supply is lost and habitat is decreased, but the outlook is not good (EPA 2001).
In general, global warming will have unusual consequences for many ecosystems. For example, many wetlands
will dry up and deserts will get rain. Soil moisture will likely decline as temperatures increase and more
water is evaporated. Storm frequency will increase as more water evaporates. Aquatic life may suffer, as ocean
temperatures will increase as well. There are many possible detrimental effects of global warming, and thus it
is necessary to address these problems now. Congress is beginning to recognize this, and several of their proposed
solutions are outlined below.