Climate Change and its Impact on Water and Agriculture

At the "Climate Change: Its Impact on Water Resources and Agriculture" lecture on Tuesday, Sept. 30, part of the distinguished scientists lecture series, two things were clear: the Earth is warming, and humans are causing it. Dr. Jeremy Pal, an assistant professor of civil engineering and environmental science at Loyola Marymount University, and a member of the Intergovernmental Panel on Climate Change (IPCC), presented a comprehensive summary of current facts on climate change compiled by the world's top scientists and assessed by the IPCC, which along with former U.S. Vice President Al Gore, received a Nobel Peace Prize for its achievements in 2007.

Pal has gone a long way to end up with IPCC. In high school, he said his goal was "to become a motorcycle racer." After graduation he enrolled at Santa Monica College, and was soon on academic probation. His course changed when he took an ecology class, and inspired by his professor, decided to study environmental science and help protect the environment. "The best professors you're going to get are here," Pal said about SMC.

The greatest value of the Pal's lecture lies in the fact that it offered the most up-to-date research and modeling data on human impact on climate, more than enough to dispel doubt or discredit any critic of the existence of the anthropogenic climate change. Pal said that due to greater evidence in the most current report (AR4, in 2007) the IPCC states that the warming of the planet is due to the increase of greenhouse gas concentration, something previous reports could not say confidently.

According to Pal and the ICC there is also "no debate that [the warming] is due to human activity." To emphasize that there really is not much controversy in the climate change controversy, Pal showed in his presentation that among 928 peer-review papers, zero had disagreed with the consensus view. In contrast, out of 636 newspaper articles 53 percent gave "roughly equal treatment" to the opposing view, that humans are not responsible for altering the planet's climate.

A good part of Pal's presentation focused on models and future projections of climate change. Pal showed graphs of temperature and carbon dioxide content in the atmosphere according to a "conservative" model and one he called "business as usual" model. According to the former model (which Pal classified as highly unrealistic) CO2 levels could rise by nearly 40 percent by 2100, or by over 150 percent according to the latter more realistic model. The temperature could rise by three to 11 degrees Fahrenheit.

The affects of climate change cannot be certain, but it will definitely have a broad impact on public health, agriculture, water resources, and biodiversity. The most likely scenario for changing climate patterns is the increase of frequency and intensity of extreme weather event.
The increase of those such as record hot or cold days, heat waves, and extreme precipitation is very likely or virtually certain. Majority of the warming takes place in high latitudes, providing some possible benefits, like higher agricultural productivity.
However tropical regions, such as Africa, will suffer more drought and decreased productivity. The early snow melt associated with warmer temperatures could present water management problems for places like California, which relies on much of its water supply from snow melt.
According to the IPCC models the low latitude regions, which already house many impoverished regions would have a greater negative impact from anthropogenic climate change than many industrialized nations, located in high latitudes.
Ironically, those nations account for almost half of carbon emissions, and only 20 percent world population. "Climate change does not have political boundaries...but unfortunately it is a political issue," Pal said. To solve this problem "we need to think not just as Americans, but in a global sense."