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Intensification of Heat Waves

From: Our Changing Climate: Assessing the Risks to California (pdf)

One important aspect of climate change is how the amount of warming may differ from season to season and how it will play out over the California landscape. Summer temperatures are likely to increase more than those in winter, and the amount of projected warming varies throughout the state. While much is reported about the average changes in temperature, it is more the projected increase in extreme conditions, which pose the most severe health related risks.

Historically, most of our heat waves have occurred in July and August, but as climate warming arises, these events will likely begin to appear earlier in the season and could continue through the Fall period, while summer events become more frequent and more intense. And, within a given heat wave, there is an increasing tendency for multiple hot days in succession – heat waves last longer. Especially important may be the lack of nighttime cooling that has characterized recent heat waves in California, and the projection that the occurrence of events having durations of 5 days or longer will become much more prevalent by the last decades of the 21st Century, putting huge strains on our health and utility infrastructure.

By 2100, if temperatures rise to the higher warming range, there could be up to 100 more days per year with temperatures above 90°F in Los Angeles and above 95°F in Sacramento. As  temperatures rise, Californians could face greater risk of death  from dehydration, heat stroke/exhaustion, heart attack, stroke, and respiratory distress caused by extreme heat. By mid century, extreme heat events in urban  centers such as Sacramento, Los Angeles, and San Bernardino could cause two to three times more heat-related deaths than occur today.

Post last edited on: 2011 April 13

Tags: extreme heat, temperature

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1 Sarah Van Wart says...

this is a test comment.

Posted at 5:39 p.m. on April 13, 2011


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