CA is “Extra Vulnerable” to Climate Change

3115732217_d7901f1545_m.jpgClimate change will most likely affect California more dramatically than it does many other places, according to researchers speaking Tuesday at the American Geophysical Union’s annual meeting in San Francisco. The panel featured new research into climate change impacts on sea level rise, agriculture, water evaluation and planning, air pollution, and extreme climate events.

Climate researcher Dan Cayan, from the Scripps Institution of Oceanography, described California as “extra vulnerable” to climate change and gave a broad (and somewhat scary) overview of the reasons why. The state’s temperature increases are expected to be similar to the global average temperature rise in the coming decades, making for hotter summers with longer heat waves. Given the expected increase in population in California’s interior, longer and harsher heat waves could have significant public health implications.

On top of the more intense summers and milder winters, precipitation across the state may well decrease, especially in Southern California. These drier conditions will be compounded by a significant withering of the Sierra snowpack. Even with a moderate increase in temperature (2 degrees C), Cayan says more than half of the historic California snowpack will disappear by 2100, as the mountains get more rain than snow at higher elevations. That can increase flooding and coupled with expected sea rise over the next century, the San Francisco Bay and the Sacramento/San Joaquin Delta may be in for some extreme events.

Fortunately, others are looking into sea level rise and what it’s going to mean for the San Francisco Bay Area and the coast of California. Peter Gleick, president and founder of the Pacific Institute, spoke about a new study currently under review focused on the projected impacts of sea level rise, including flooding and erosion, and the potential responses. The study will evaluate flood and erosion potential, create detailed maps of California’s vulnerable areas, estimate risks to populations and structures, anticipate costs of various adaptation strategies, and make policy recommendations. Gleick cited one immediate need as a catalog of the state’s existing levees and their conditions.

The report’s results should be out in February, which is also when we should see the draft version of the first California Adaptation Strategy, which aims to compile information on expected climate change impacts for the state and provide policymakers and resource managers with strategies for addressing them.