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Pacific pattern provides early heat wave warning

Image: Heat map
A color-coded map shows how hot temperatures got on June 29, 2012, with the reddest region indicating temperatures above 100 degrees Fahrenheit. A model based on Pacific sea surface temperatures could predict such a heat wave up to seven weeks in advance. (Credit: NWS Weather Prediction Center)

Meteorologists say they’ve found a pattern in Pacific Ocean sea surface temperatures that could help authorities prepare for heat waves in the eastern United States up to 50 days in advance.

Now that the pattern has been found, forecasters will start keeping track of the heat wave indicators in May. But don’t expect the 50-day forecast to show up in the nightly weather report.

“Most seasonal predictions, including this one, are probabilistic rather than deterministic,” lead author Karen McKinnon, a climate scientist at the National Center for Atmospheric Research in Colorado, explained in an email. “For example, we can predict an increase in the odds in favor of having a hot day in the Eastern U.S. from about 1 in 6, to 1 in 2, at lead times of 40 days if the Pacific Extreme Pattern is particularly strong.”

She said the indicators are most likely to come into play during preparations for the peak of the summer.

“For example, city leaders could ensure they have sufficient cooling rooms for the elderly or those without air conditioning; farmers could alter their management tactics to prevent crop loss; businesses could be prepared for increased demand of air conditioners and fans; and utilities could ensure they have sufficient power options available to bring online quickly in case of a spike in demand,” she said.

The research was published today by Nature Geoscience. One of the authors, Andy Rhines, is a climate scientist at the University of Washington.

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Scientists trace link between the moon and rain

Image: TRMM
Readings from the Tropical Rainfall Measuring Mission, shown in this artist’s conception, provided evidence to support a link between lunar tides and rainfall patterns. (Credit: NASA)

When the moon is high in the sky, its gravitational pull warps the atmosphere enough to reduce rainfall ever so slightly. At least that’s the conclusion that researchers from the University of Washington reached after reviewing 15 years of detailed rainfall data.

The evidence is laid out in a paper to be published in Geophysical Research Letters.

Readings from the U.S.-Japanese Tropical Rainfall Measuring Mission, collected between 1998 and 2012, suggest that rainfall is reduced by about 1 percent if the precipitation falls when the moon is directly overhead or underfoot.

Those findings are in sync with a 2010 study that laid out a similar link between phases of the moon and precipitation. Both papers show that lunar tides have an effect on the atmosphere.

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Inside the flying lab that’s probing rain clouds

Image: DC-8 view
The view out the window during NASA’s DC-8 flight on Saturday. (GeekWire photo by Alan Boyle)

JOINT BASE LEWIS-McCHORD, Wash. – I’ve looked at clouds from both sides now – from below, on the receiving end of an all-day rain; and from above, where NASA’s flying laboratory is dissecting those rain clouds.

For more than six hours on a rainy Saturday, I rode along as a DC-8 jet bristling with electronic gear took radar and microwave measurements of the clouds hanging over the Olympic Peninsula. The flight is part of a months-long campaign called the Olympic Mountain Experiment, or OLYMPEX, which is being conducted by NASA and the University of Washington.

OLYMPEX is aimed at fine-tuning the algorithms that scientists use to translate the data coming from on-the-ground weather installations and satellites like the recently launched Global Precipitation Measurement Mission Core Observatory into weather and climate projections.

In the process, they’re addressing a scientific problem we’ve known about since Judy Collins first sang about clouds in the ’60s: We really don’t know clouds at all.

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Rain-measuring mission gets a good, soggy start

Image: DC-8
Members of a NASA Social group at Joint Base Lewis-McChord get ready to tour a DC-8 plane that NASA is using to document rainfall on the Olympic Peninsula. (GeekWire photo: Alan Boyle)

JOINT BASE LEWIS-McCHORD, Wash. — The weather forecast for the Olympic Peninsula is dark and rainy, and that’s putting the scientists behind NASA’s OLYMPEX campaign in a sunny mood.

“The really exciting thing that everyone’s talking about is, there’s this huge rain event that’s coming in,” says Rachael Kroodsma, an atmospheric scientist from NASA’s Goddard Space Flight Center, helping to get a specially outfitted DC-8 plane ready to fly into the storm this week. “There’s a lot of buzz about that. … It’s a good start to the campaign.”

Usually, bad weather is bad news.

Not for OLYMPEX, the Olympic Mountain Experiment.

Under the leadership of NASA and the University of Washington, the months-long effort is using aerial observations as well as a bevy of radars and rain gauges to validate orbital data from the Global Precipitation Measurement satellite, also known as GPM. The $3 million campaign is the latest of several field studies aimed at making sure the satellite readings reflect ground truth.

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Forbes

Scientists raise alarm over Persian Gulf climate

Image: Hajj
Hundreds of thousands of Muslim pilgrims pray outside the Namira Mosque near Mecca on Sept. 23 during this year’s hajj pilgrimage in Saudi Arabia. (AP file photo by Mosa’ab Elshamy)

Climate researchers say that summertime conditions in some parts of the Persian Gulf region could become intolerable by the end of the century – and that the annual hajj pilgrimage, a core observance for Muslims, is ”likely to become hazardous to human health.”

“The main day of the pilgrimage involves worshiping at a site outside Mecca from sunrise to sunset in an outdoor setting. … That’s the kind of ritual that could be quite limited,” said Elfatih Eltahir, a climatologist at the Massachusetts Institute of Technology who is one of the authors of a report published today by Nature Climate Change.

Eltahir and his co-author, Jeremy Pal of Loyola Marymount University, base their projections on an analysis of the potential regional effects from global climate change under two of the scenarios laid out by the Intergovernmental Panel on Climate Change. One scenario assumes “business as usual” and a steady rise in greenhouse gas emissions. The other, known as the RCP4.5 scenario, assumes the rise in emissions can be stabilized.

The analysis suggests that if current trends continue, summertime heat and humidity would occasionally rise beyond the limit of human endurance in Abu Dhabi and Dubai; in Qatar’s capital, Doha; in the Saudi city of Dhahran and the Iranian port of Bandar Abbas. Temperatures in Mecca wouldn’t hit the threshold by the end of the century, but they’d come close.

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Hurricane Patricia looks scary from space

VIIRS view of Hurricane Patricia
An infrared image from the Suomi NPP satellite’s VIIRS instrument shows the well-defined eye of Hurricane Patricia as of 9:20 GMT Friday. (Credit: NASA / NOAA / CIMSS)

Even the International Space Station’s commander is worried about Hurricane Patricia, the strongest storm ever tracked by the National Hurricane Center.

NASA astronaut Scott Kelly, who is currently heading the station’s crew during his yearlong tour of orbital duty, passed along a picture showing the monstrous whirl of white clouds as it approached Mexico today:

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