Figure 1. CO 2 Level Increase over Time.
Source: (NASA 2008)One such effect of this warming is a rise in the glob-
al sea level. Since 1993, the global sea level rose 3mm
per year— nearly doubling the previous rate of 1.7mm
per year experienced during most of the 20th century.
The rise in sea level has varied drastically around the
globe, however, as sea levels along the U.S. Mid-At-
lantic and Gulf Coasts rose 5-6 inches more than the
global average due to subsiding of coastal lands (EPA
2011).
Temperature and precipitation changes vary
across the planet, with some changes in ecosystems
occurring at a vastly larger rate and magnitude than
scientists previously anticipated. For example, the
temperatures in the Arctic are rising at almost dou-
ble the overall global rate, whereas in general, tem-
peratures are rising faster over land masses than over
open oceans (IPCC 2007b). Over the last hundred
years, land masses north of 30 degrees latitude have
experienced more precipitation while the tropics have
experienced less since the 1970s (IPCC 2007b). Other
evidence of climate change is demonstrated in the
thawing of the northern latitude permafrost and an