New insights into predicting future droughts in California: Natural cycles, sea surface temperatures found to be main drivers in ongoing event

According to a new NOAA-sponsored study, natural oceanic and atmospheric patterns are the primary drivers behind California's ongoing drought. A high pressure ridge off the West Coast (typical of historic droughts) prevailed for three winters, blocking important wet season storms, with ocean surface temperature patterns making such a ridge much more likely. Typically, the winter season in California provides the state with a majority of its annual snow and rainfall that replenish water supplies for communities and ecosystems.

Further studies on these oceanic conditions and their effect on California's climate may lead to advances in drought early warning that can help water managers and major industries better prepare for lengthy dry spells in the future.

"It's important to note that California's drought, while extreme, is not an uncommon occurrence for the state. In fact, multi-year droughts appear regularly in the state's climate record, and it's a safe bet that a similar event will happen again. Thus, preparedness is key," said Richard Seager, report lead author and professor with Columbia University's Lamont Doherty Earth Observatory.

This report builds on earlier studies, published in September in the Bulletin of the American Meteorological Society, which found no conclusive evidence linking human-caused climate change and the California drought. The current study notes that the atmospheric ridge over the North Pacific, which has resulted in decreased rain and snowfall since 2011, is almost opposite to what models project to result from human-induced climate change. The report illustrates that mid-winter precipitation is actually projected to increase due to human-induced climate change over most of the state, though warming temperatures may sap much of those benefits for water resources overall, while only spring precipitation is projected to decrease.

The report makes clear that to provide improved drought forecasts for California, scientists will need to fully understand the links between sea surface temperature variations and winter precipitation over the state, discover how these ocean variations are generated, and better characterize their predictability.

This report contributes to a growing field of science-climate attribution-where teams of scientists aim to identify the sources of observed climate and weather patterns.

"There is immense value in examining the causes of this drought from multiple scientific viewpoints," said Marty Hoerling, report co-author and researcher with NOAA's Earth System Research Laboratory. "It's paramount that we use our collective ability to provide communities and businesses with the environmental intelligence they need to make decisions concerning water resources, which are becoming increasingly strained."

To view the report, visit:?http://cpo.noaa.gov/MAPP/californiadroughtreport.

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Billion-Dollar Disasters 'Harbinger' of Future Extreme Weather: NOAA (LiveScience.com)

SAN FRANCISCO — The 12 $1-billion-plus disasters that hit the United States this year are most likely not simply a matter of the stars aligning against us, according to the head of the National Oceanic and Atmospheric Administration (NOAA), who implicated climate change as a contributor. 

Climate change, caused by carbon dioxide and other greenhouse gases humans have emitted, is expected to increase certain types of extreme weather, leading to more disasters, according to a report being assembled by the Intergovernmental Panel on Climate Change (IPCC).

"The report that was released by the IPCC on extreme events suggests that what we are seeing this year is not just an anomalous year, but a harbinger of things to come for at least a subset of the extreme events we are tallying,"said Jane Lubchenco, NOAA's administrator, during a press conference held here this week at the annual American Geophysical Union meeting.

A summary of the report released in November predicts an increase in certain types of extreme weather, including daily high temperatures, heat waves, heavy precipitation and droughts, in some places. [Photos of Devastating Texas Drought]

Costly disasters

With this increase in extreme weather there will likely be an associated uptick in costs. Earlier Wednesday (Dec. 7) the agency announced that this year, so far, had broken the record for costly, weather-related disasters,including drought, wildfire, tornados, flooding, a blizzard and a hurricane. She noted that the agency is still tallying costs related to Tropical Storm Lee and the unseasonable snowstorm in the Northeast that occurred over Halloween weekend.

"I believe there are probably four reasons why we are seeing an increase," said Lubchenco, referring to the number of costly events. "One is there are more extreme events, period, but it is more complicated than that," Lubchenco said, adding that the country now has more people, who have more stuff to lose in disasters, and more people and their stuff now reside in harm's way, such as along the coasts. More people also have insurance that pays for their losses, magnifying the costs associated with a disaster.  

The previous record, for nine $1-billion-or-more weather-related disasters was set in 2008.

Climate-change connection

Of the types of extremes that battered the country this year, only certain large-scale phenomena among them —such as heat waves, droughts and heavy precipitation —have links to climate change.

"We are likely to see more and more of them down the road as climate continues to change," she said.

The connection between small-scale extreme events, such as a localized hailstorm or a tornado, and climate change is less understood, she said.

Since about 1970, NOAA's Climate Extreme Index —which tracks the percentage of the country affected by climate extremes over time —has shown an upward trend that is notably different than the activity in earlier decades, she told an audience of scientists at a talk earlier in the day.

This trend is driven by daily highs and lows, availability of water and heavy precipitation in a single day. Most notably, since 1970, more of the country is experiencing unusually warm nights, with less of the country experiencing unusually cool nights. This particular shift is significant, she said: "Warm overnight lows are related to heat stress in both people, and plants and animals; they never get a chance to cool off."

Likewise, while the country has had periods of severe drought, such as during the Dust Bowl of the 1930s, it has never become drier and wetter at the same time, as has happened in the last decade, she said.

You can follow LiveScience senior writer Wynne Parry on Twitter @Wynne_Parry. Follow LiveScience for the latest in science news and discoveries on Twitter @livescience and on Facebook.

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Weather Satellites Vital to NASA's Future (ContributorNetwork)

As the space shuttle program comes to a close, NASA will look to the future with robotic probes of other planets. Another major part of the space agency's mission will be to launch weather satellites to observe the Earth's always-changing weather patterns.

There are several satellites in orbit now that help scientists determine how and when weather will change on our planet.

GOES/POES

The Geostationary Operational Environmental Satellite (GOES) program has satellites that stay in one particular spot in orbit over the Earth. This system uses infrared and visual photographs of the Earth's atmosphere to help scientists spot incoming weather from over the oceans.

Another system of satellites is called the Polar Operational Environmental Satellites (POES) and are in polar orbits over the Earth. As such, satellites go over both the North and South Poles on a regular basis and take pictures and measurements.

Both satellite systems are run by the National Atmospheric and Oceanic Administration. Weather photos are downloaded to the NASA website on a regular basis for anyone to observe. Dozens of satellites are in orbit to help monitor weather from above the planet and give a bird's-eye view of atmospheric conditions.

NPP

A set of polar-orbiting satellites are preparing for launch in the near future. As a transition from older satellites to ones with newer sensing equipment, NASA will launch the NPOESS Preparatory Project (NPP) to get ready for the next generation of climate-observing vehicles.

A series of environmental satellites will be used to detect climatological changes in the Earth. Earlier models involved two satellites called Terra and Aqua. The launch of the NPP satellite in late 2011 will provide a bridge until the launch of the Joint Polar Satellite System in 2015.

At 512 miles above the Earth , these satellites with also have polar orbits. Their main goal is to take pictures and measurements of the Earth's atmosphere in order to better understand climate change. The Earth Observing System (EOS) will also be able to measure ocean temperatures and will be able to view changes to land and ocean with more sensitive equipment and better technology than ever before.

Observing the Earth is one mission NASA has been developing since the mid-1960s with the launch of the Tiros and Nimbus series. When NASA focuses more on robotic and Earth science with the completion of the space shuttle program, weather satellites will be more important to the future of mankind on Earth.

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Future of levee blown to save Illinois town unclear, Corps says (Reuters)

SIKESTON, Mo (Reuters) – The federal government has not decided whether it will rebuild the Mississippi River levee intentionally destroyed last month to relieve flooding in Cairo, Illinois and other towns, an official said on Thursday.

Jim Pogue, a spokesman for the Memphis District of the Army Corps of Engineers, told Reuters a final decision on the future of the Birds Point-New Madrid levee near here would not come "for months."

Pogue said the Corps was studying the performance of the whole system of levees and floodways along the Mississippi after this spring's record flooding and any decision on Birds Point-New Madrid would be made as part of that larger study.

He said it has been a "challenge" to find money to replace levees along the river and the Corps had been working with Congress to identify possible revenue sources.

The levee at Birds Point-New Madrid was deliberately destroyed by the Corps on May 2, flooding over 100,000 acres of prime farmland in Missouri. Some farmers sued the Corps over the decision to blow the embankment, which lowered the water level on the Mississippi by allowing water to rush into a spillway that had not been used since 1937.

A snowy winter and rainy spring have caused record flooding on the Ohio, Mississippi and Missouri Rivers this year.

To cope with Mississippi water levels that approached or beat records set in 1927, the Corps also opened up the Morganza and Bonnet Carre spillways last month. It was the first time that all three floodways were opened in the same year.

(By Barton Lorimor; Writing by James B. Kelleher and Mary Wisniewski; Editing by Jerry Norton)

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