Tag: La Niña

Emerging La Niña likely to end streak of record-warm years

Pacific Ocean ENSO cycle a key player in global climate

La Niña
Cooler water welling up along the coast of South America and moving west suggests the start of La Niña in the Pacific Ocean.

By Bob Berwyn

The shift from a powerful El Niño to the cooler La Niña phase of Pacific Ocean temperatures will temporarily end the planet’s recent record streak of record-warm years, according to climate scientists who see the cyclical ocean changes as a key factor in the long-term global climate change equation.

Nearly all record-warm global years since 1950 (when accurate records start) have come during during El Niños, when the Pacific Ocean releases heat to the atmosphere and  intensifies global warming caused by heat-trapping greenhouse gas pollution. The 2015-16 El Niño was one of the strongest on record, but it has now ended, according to the National Oceanic and Atmospheric Administration, which says sea surface temperatures in the central and equatorial Pacific have cooled to average in the past few weeks. Continue reading “Emerging La Niña likely to end streak of record-warm years”

Study eyes coastal impacts of El Niño cycles

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If climate change intensifies El Niño and La Niña, it could have big impacts on coastal erosion. @bberwyn photo.

Coastal Pacific areas seen as vulnerable to intensifying storms

Staff Report

If global warming strengthens the cycle of El Niño and La Niña events — as projected by some studies — it could lead to an increase in storm events bringing extreme coastal flooding and erosion in populated regions across the Pacific Ocean, according to a multi-agency study published today in Nature Geoscience.

“This study significantly advances the scientific knowledge of the impacts of El Niño and La Niña,” said Patrick Barnard, USGS coastal geologist and the lead author of the study. “Understanding the effects of severe storms fueled by El Niño or La Niña helps coastal managers prepare communities for the expected erosion and flooding associated with this climate cycle.” Continue reading “Study eyes coastal impacts of El Niño cycles”

Climate: When good ozone goes bad

Western U.S. Counties Violating Current and Proposed Ozone Air Quality Standards.
Western U.S. counties violating current and proposed ozone air quality standards. Map courtesy Jeremy Nichols/ClimateWest blog.

La Niña weather pattern found to contribute to spikes in western ozone levels

Staff Report

FRISCO — Spring ozone formation in parts of the western U.S. appear to be linked with the hemispheric La Niña weather pattern, when the path of the jet stream forces high altitude ozone down to ground level.

After discovering the link, a team of researchers say their findings may help forecast harmful ozone episodes well in advance, which could have implications for attaining the national ozone standard. Continue reading “Climate: When good ozone goes bad”

Climate: Does La Niña increase the odds of tornadoes?

Finding a signal amidst the climate noise isn’t easy

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Does La Niña increase the odds of tornadoes?
A new NOAA study tracks the occurrence of seasonal tornadoes across the U.S.
Study finds links between ENSO and tornado frequency in the Southern U.S. Photo courtesy NOAA.

Staff Report

FRISCO — Teasing out a link between large-scale atmospheric patterns and specific weather events isn’t easy against the backdrop of natural variability.

But a new study of the El Niño-La Niña cycle in the Pacific Ocean suggests that La Niña — the cool phase of the cycle — increases the frequency of tornadoes and hail storms in some of the most susceptible regions of the United States.

During La Niña, both vertical wind shear and surface warmth and moisture increase significantly in the southern states, making conditions favorable to severe storm occurrence.

The study, published in the current issue of the journal Nature Geoscience, may help provide more information for medium- and long-range extreme weather forecasts. Continue reading “Climate: Does La Niña increase the odds of tornadoes?”

More climate clues from ancient corals

Mapping coral diseases is helping researchers determine the cause. Photo courtesy NOAA.
Coral reefs near Panama stopped growing during an exstended phase of La Niña-like conditions in the Pacific Ocean. Photo courtesy NOAA.

‘It’s possible that anthropogenic climate change may once again be pushing these reefs towards another regional collapse …’

Staff Report

FRISCO — Past climate shifts resulting in La Niña-like conditions off the coast of Panamá resulted in a 2,500-year shutdown in coral reef growth, scientists said this week, warning that human-caused global warming could lead to similar conditions in the coming decades.

“We are in the midst of a major environmental change that will continue to stress corals over the coming decades, so the lesson from this study is that there are these systems such as coral reefs that are sensitive to environmental change and can go through this kind of wholesale collapse in response to these environmental changes,” said Kim Cobb, an associate professor in the School of Earth and Atmospheric Sciences at the Georgia Institute of Technology. Continue reading “More climate clues from ancient corals”

Climate study predicts doubling of extreme La Niñas

Will global warming intensify extreme weather swings?

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How will climate change affect ENSO?

Staff Report

FRISCO — Global warming could increase the frequency of extreme La Niña events in the Pacific Ocean, with more droughts in southwestern United States, floods in the western Pacific regions and increased Atlantic hurricane activity.

The international study, published in Nature Climate Change, used advanced modeling to show how increased land-area heating, combined with more frequent El Niños, will feed a cycle of extreme La Niñas. Continue reading “Climate study predicts doubling of extreme La Niñas”

Climate: Is the Southwest ‘stuck’ in a drought pattern?

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NOAA’s winter outlook offers little relief for Arizona, New Mexico

By Bob Berwyn

FRISCO — Drought conditions may persist across the southwestern U.S. this winter and may redevelop across the Southeast, according to the seasonal outlook from NOAA’s Climate Prediction Center.

“Even though we don’t have La Niña, the atmosphere across the Pacific seems to be stuck in a La Niña mode … It’s been quite surprising to us, how persistent the pattern is,” said Mike Halpert, acting director of the Climate Prediction Center.

Parts of the Southwest, especially New Mexico, have been experiencing one of the driest periods on record, and Halpert said there is “decent agreement” in the CPC’s models on the climate signal that has resulted in the persistent trend. Continue reading “Climate: Is the Southwest ‘stuck’ in a drought pattern?”