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Study: Ancient El Niño just as strong as today’s

Archaeologists, ocean scientists team up on detailed study of historic climate cycles in Pacific Ocean

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Study offers new clues to past and future El Niños.

Staff Report

FRISCO — Today’s climate models may not do a very good job of predicting changes in the Pacific Ocean El Niño-La Niña cycle, an international team of  scientists said after studying old seashells that display a distinct history of climate variations.

Understanding how El Niño responds to global warming is significant because the undulating rhythm of warming and cooling waters in the equatorial Pacific is a key driver of weather patterns around the world. Some modeling studies have suggested that ancient El Niños may have been weaker than today’s but the new research suggests they were as strong and as frequent as they are now, at least going back about 10,000 years. Continue reading

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Morning photo: Waves

Seashore thrills …

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A gentle Gulf of Mexico breaker rolls ashore under a setting sun.

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Living in the small side-house to the barn-like fog signal building at Pt. Montara, California gave me a deep appreciation of ocean waves.

FRISCO — In the early 1980s I lived at the Pt. Montara Lighthouse, about 20 miles south of San Francisco. While we renovated the Victorian lighthouse keeper’s quarters, I stayed in the watchroom of the fog signal building, just 10 yards from the edge of a bluff overlooking a rocky headland that juts far into the Pacific. As it turned out, the first winter I lived there was a big El Niño year. Endless storms crashed ashore from November through May, coating my oceanfront window with salt spray and, at times, making the cliffs shake. It’s hard to describe the size and scope of these breakers, but if you’ve seen the movie “Chasing Mavericks,” it’ll give you an idea of the 30- to 40-foot walls of water that were commonplace that year. I already was a big fan of waves before that, but the experience gave me a whole new appreciation for the power of the sea. I don’t have any digital images of that winter, but I probably do have some old slides tucked away in a shoebox. I was tempted to try and find them, but I’ll save that for another time. Continue reading

Climate: For El Niño, timing is everything

Study identifies wind patterns that could lead to better El Niño forecasts

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El Niño affects global weather patterns.

By Summit Voice

SUMMIT COUNTY — Climate researcher say they’ve discovered an atmospheric pattern that helps explain why El Niño often peaks during the first part of winter and usually fades away in late winter and early spring.

El Niño phases are part of a cycle when sea surface temperatures in the equatorial Pacific Ocean are warmer than average. The various phases of the so-called ENSO can have pronounced impacts on weather around the globe, spurring droughts in some areas and flooding in others.

The new study from the University of Hawai’i at Manoa Meteorology Department and International Pacific Research Center identified an unusual wind pattern that straddles the equatorial Pacific during strong El Niño events and swings back and forth with a period of 15 months as a key driver in the annual cycle. The findings were reported in the May 26 online issue of Nature Geoscience. Continue reading

Study: Sea level changes may affect tropical rainfall patterns

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How will global warming affect global atmospheric circulation and precipitation patterns? Photo courtesy NASA’s Blue Marble collection.

At lower sea levels, exposed land masses could affect convection

By Summit Voice

FRISCO — Even though scientists are continuously fine-tuning their global warming models, climate change is likely to dish up some big surprises in the decades ahead.

In one recent study, researchers with the University of Hawaii and Woods Hole Oceanographic Institution found evidence that past changes in sea level rise had a somewhat unexpected influence across the center of the Indo-Pacific warm pool — a vast region of warm ocean waters in the western Pacific region that is the main source of heat and moisture to Earth’s atmosphere. Continue reading

Fukushima ocean radiation panel to be live-streamed

Experts to discuss concerns about radioactive dispersion; viewers can ask questions via Twitter during May 9 session

FRISCO — More than two years have passed since a 9.0 earthquake and a 50-foot tsunami catastrophically damaged the Fukushima Dai-ichi nuclear power plant on Japan’s northeast coast, but questions still linger about the long-term impacts of radioactive pollution in the ocean.

The quake and tsunami killed about 20,000 people, and some coastal Japanese fisheries are still closed due to concern about the radiation. Next week, an international panel of scientists will discuss the accident and potential impacts to the environment and human health in a web-streamed session at the Woods Hole Oceanographic Institution.

The panel will be held on May 9, 2013, from 6:30 to 9:30 p.m. EDT and simulcast on the Web (http://www.whoi.edu/fukushima). Online viewers are encouraged to participate and send questions for the panel discussion via Twitter. The event hashtag is #WHOIfukushima. Questions during the discussion can also be sent via email to cmer@whoi.edu. Continue reading

New research may help pinpoint Asian monsoon

Regional pressure fluctuations the key to unraveling monsoon mysteries

The first week of August 2010 brought extreme flooding and landslides to many parts of Asia. By August 11, floods in the Indus River basin had become Pakistan’s worst natural disaster to date, leaving more than 1,600 people dead and disrupting the lives of about 14 million people, reported Reuters. Across the border in northeast India, flash floods killed 185 with 400 still missing, reported BBC News. Floods in North Korea and northeast China buried farmland and destroyed homes, factories, railroads, and bridges. And in northwest China, rain triggered a massive landslide that left 702 dead with 1,042 missing, reported China’s state news agency, Xinhua. All of these disasters occurred as a result of unusually heavy monsoon rains, depicted in this image.

The first week of August 2010 brought extreme flooding and landslides to many parts of Asia. By August 11, floods in the Indus River basin had become Pakistan’s worst natural disaster to date, leaving more than 1,600 people dead and disrupting the lives of about 14 million people, reported Reuters. Across the border in northeast India, flash floods killed 185 with 400 still missing, reported BBC News. Floods in North Korea and northeast China buried farmland and destroyed homes, factories, railroads, and bridges. Photo courtesy NASA Earth Observatory.

By Summit Voice

FRISCO — Hawaii-based scientists say that tracking hemispheric climate patterns can help develop more accurate forecasts for the critical Asian monsoon season, which is critical to  the agriculture, economy, and people in the region.

Better monsoon forecasts have been a sort of Holy Grail for meteorologists, but season  seasonal predictions of these two types of weather phenomena are still poor. But the research done at the International Pacific Research Center, University of Hawaii at Manoa, shows the strength of the East Asian summer monsoon and  storm activity in the western North Pacific depend on fluctuations in the western Pacific Subtropical High, a major atmospheric circulation system in the global subtropics centered over the Philippine Sea.

When this system is strong in summer, then monsoon rainfall tends to be greater than normal over East Asia, and in the western North Pacific there tend to be fewer tropical storms that make landfall. Continue reading

New coral data traces 7,000 years of El Niño history

20th century oscillations show intensification that may be linked with global warming

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A NOAA graphic showing early January 2012 ocean surface temperature anomalies.

By Summit Voice

SUMMIT COUNTY — Atmospheric scientists say they’ve used coral records to trace the history of El Niño cycles going back about 7.000 years, showing that 20th century oscillations  are much stronger than those captured in the fossil record.

But the study also showed large natural variations in past ENSO strength, making it difficult to attribute the 20th century intensification of ENSO to rising carbon dioxide levels. Such large natural fluctuations in ENSO activity are also apparent in multi-century climate model simulations, but the 20th century intensification stands out as statistically significant and could be linked with global warming.

The new information will help assess the accuracy of climate model projections for 21st century climate change in the tropical Pacific. Continue reading

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