extreme weather


California’s Farm Belt Didn’t Dodge the Summer Heat Wave

Abnormally warm summer temperatures were felt across much of interior California

By Nicholas Christen and Craig Miller

Even tomatoes can only take so much heat. A belt from Bakersfield to the northern Sacramento Valley produces a third of the nation's canning tomatoes.

Autumn is here, so says the calendar. Living on the coast, it might be easy to think that California escaped the heat wave suffered by much of the nation this summer. While that may be true for most of the large coastal population centers, it was a different story for much of the state’s interior farm belt.

Throughout June and July, even Central Valley spots escaped much of the heat felt by the Great Plains, though Cal Expo officials blamed the heat, in part, for tamping down attendance at the state fair. Then things heated up quickly — especially in the Sacramento and San Joaquin Valleys — through August and into September.  Valley towns including Redding, Red Bluff, Sacramento, Merced, Madera, Fresno, and Bakersfield, have been on the order of three-to-five degrees above normal for the duration of August and September. Continue reading

Heat Wave: California Takes its Turn

Forecast for inland temperatures to stay in the triple-digits this week

High temperatures in the Central Valley are expected to last through the end of the week.

America’s heat wave has caught up with California — at least the inland areas.

Sacramento has had six consecutive days above 100 degrees; an excessive heat warning is in effect from Merced to Bakersfield; and on Saturday Modesto tied its record for highest temperature for the date, at 105 degrees.

“In general, we’re about ten-to-fifteen degrees above normal for this time of year,” Holly Osborne, a meteorologist with the National Weather Service in Sacramento told me. “Today will be our sixth day of 100 or above in Sacramento, and we’re looking at temperatures being 100 or above for the rest of the week.” Osborne expects things to cool off, “moving into the weekend.” Continue reading

Understanding the U.S. Drought and Heatwave: Five Good Visuals

As the drought drags on, these graphics and interactives explain what’s happening

1. “Drought’s Footprint”The New York Times

In June, more than half of the U.S. was experiencing moderate to extreme drought. How does that compare to other years? The Times’ graphic lays it out.

2. “Dried Out: Confronting the Texas Drought” — NPR, KUT and KUHF

The drought began in Texas in October of last year. Watch it grow over time, and explore a timeline that explains the root causes of the drought and how communities are responding.

3. “Flash Drought in U.S. Explained in 14 Seconds”Climate Central

Watch an animation showing the spread of the drought, from Texas and Georgia in March, to most of the Midwest and West by June.

4. Drought Impact Reporter — The National Drought Mitigation Center

This is “the nation’s first comprehensive database of drought impacts.” Submit reports of how the drought affects you, and search for drought impacts by state, whether they’re to agriculture, industry, public health or wildlife.

5. “Historic heat wave in hindsight: Hottest on record in Washington D.C., hotter than 1930”Washington Post

From the Post’s weather blog, a local, numbers-heavy analysis of the heatwave that hit Washington. With stats like “Longest period at or above 100: 7 hours on July 7 (tie with July 6, 2010 and July 21, 1930),” it’s like a Guinness Book of World Records for D.C.’s summer, and holds my usually California-focused attention.

Drought Has Ties to La Niña, with Global Warming Assist

La Niña has been linked to historical droughts, including the Dust Bowl


A cow feeds in a drought-damaged pasture as temperatures climb near 100 degrees on July 17, 2012 near Princeton, Indiana.

Driven by a combination of natural climate variability, manmade global warming, and plain old bad luck, drought conditions are so widespread in the U.S. that it’s possible to take a cross-country flight from Washington, D.C. to San Francisco — a distance of approximately 2,400 miles — without once overflying an unaffected area. With about 81 percent of the lower 48 states experiencing at least abnormally dry conditions, and 63 percent mired in moderate-to-exceptional drought, it’s becoming harder and harder to find an oasis. And the dog days of August are yet to come.

The National Oceanic and Atmospheric Administration (NOAA) already ranks this drought as one of the worst on record, comparable to the drought events of the 1950s. The last time there were such widespread drought conditions in the corn-growing region of the country was in 1988, and that drought cost at least $40 billion.

Given this summer’s punishing 1-2 punch of dry weather and heat, this drought is also being compared to the Dust Bowl era of the 1930s. Continue reading

Dry Weather Boosts Odds of Extreme Heat

A new study finds that drought in one month increases the likelihood of heat in the next


As soil dries, more of the sun’s energy goes into heating the air directly, rather than evaporating moisture from the ground.

Droughts such as the one currently gripping a majority of the U.S. may dramatically increase the odds of extremely hot days, a new study found. The study, published in Proceedings of the National Academy of Sciences, explores a dynamic that is playing out right now across the country, particularly in the Great Plains, where the severe drought is priming the atmosphere in favor of an above-average number of extremely hot days.

This occurs because of feedbacks between the ground and the air: as the soil and vegetation dry, more of the sun’s energy is able to go into heating the air directly, rather than going into evaporating moisture from plants and the soil.

With drought conditions intensifying during mid-summer, the study suggests that the U.S. may be in for particularly brutal Dog Days of August. Continue reading

Why Hasn’t California Been Hit With This Summer’s Extreme Heat?

As the rest of the country roasts, California has enjoyed a moderate summer

California has not experienced the extreme heat much of the rest of the country has this summer.

For more than a week, record-breaking temperatures have been baking the Midwest and East Coast. But while cities in other parts of the country broke and tied records for the hottest Fourth of July, in San Francisco I bundled-up in a couple sweaters and watched the fireworks through the fog. Which is typical. Overall, it’s been an average summer here in California, at least temperature-wise.

“At June around the state, most places were fairly close to normal, or a degree and a half below normal, so not any real extremes,” Jan Null, a meterologist with Golden Gate Weather Services, told me. “We’ve stayed in the mild, in-between area. It was not a particularly cold winter, and not a particularly hot summer.” Continue reading

Crazy Weather? You Might Be Able to Blame the Arctic

Arctic warming is altering weather patterns, study shows

By Andrew Freedman

Path of the jet stream on March 21, 2012.

By showing that Arctic climate change is no longer just a problem for the polar bear, a new study may finally dispel the view that what happens in the Arctic, stays in the Arctic.

The study, by Jennifer Francis of Rutgers University and Stephen Vavrus of the University of Wisconsin-Madison, ties rapid Arctic climate change to high-impact, extreme weather events in the U.S. and Europe.

The study shows that by changing the temperature balance between the Arctic and mid-latitudes, rapid Arctic warming is altering the course of the jet stream, which steers weather systems from west to east around the hemisphere. The Arctic has been warming about twice as fast as the rest of the Northern Hemisphere, due to a combination of human emissions of greenhouse gases and unique feedbacks built into the Arctic climate system.

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Belief in Climate Change Depends on Which Way the Wind Blows

More people think the climate is changing, and many say the weather convinced them

People cited their experience of warmer temperatures as a major influence in their views of climate change.

Most Americans now say that the climate is changing, according to the National Survey of American Public Opinion on Climate Change (PDF). Nearly two out of three people (62%) answered “yes” to the question, “Is there solid evidence that the average temperature on Earth has been getting warmer over the past four decades?” The primary reasons they gave for that answer? About one in four said it’s because they’ve observed warmer temperatures, and an identical 24% because they’ve observed weather changes — and the survey was taken last fall, before this year’s generally mild winter in the U.S. had entered the national chatter (we recall a recent tweet from NOAA saying that Midland, TX had logged more snowfall this winter than New York, Boston and Philadelphia combined). Continue reading

This is Your Atmosphere on Drugs

A new report on extreme weather compares climate change to steroids

The tornado that tore through Joplin, MO in May was one of the worst of last year's extreme weather events. But tornadoes have one of the more tenuous connections to climate change.

As we’ve noted before, last year was packed with extreme weather events, but it’s difficult to out-and-out blame any particular one of them on climate change. Explanations are often along the lines of, “This is the kind of thing that could become the norm in the future.” The science just isn’t quite there to able to pinpoint any single event and say exactly what caused it.

To try to sort out what we know from what we don’t, the University Corporation for Atmospheric Research (UCAR), a consortium of universities doing earth science research, has a new feature on its website, “In Depth: Weather on Steroids,” about that science: the science of attribution, as in, what can we attribute to climate change?

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Insurance Industry Awakening to Climate Risks

California will require all major insurers to survey and report climate risks

Insurers in California, Washington, and New York will be required to describe the steps they're taking to address climate change.

Insurance commissioners in three states, including California, are now requiring that insurers report on how they’re preparing for climate change. Insurers will fill out a survey, which was adopted by The National Association of Insurance Commissioners (NAIC) in 2009, but was never implemented by commissioners in all fifty states. Instead, it’s been a piecemeal approach. California administered the survey in 2009 and ’10, requiring all insurers that met a minimum size requirement and that were headquartered in the state to fill it out. Now California is expanding the initiative: all insurers that write premiums worth more than $300 million and do business in the state–not just those based here–will be required to fill out the survey. New York and Washington are doing the same.

The Climate Risk Survey covers general questions: does the company have a climate change policy with respect to risk management and investment management, has the company considered the impact of climate change on its investment portfolio, does the insurer have a plan to assess or mitigate its own emissions?  Continue reading