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”

Mega-scale El Niña pattern may have big climate impacts

New findings help sharpen global warming projections

Can El Niño last for centuries?

Staff Report

A chemical analysis of cave formations in Indonesia has helped climate researchers identify a large-scale pattern of El Niño shifts in the Pacific Ocean that may play a role in how climate change plays out over the next few decades.

Measuring isotopes in the stalagmites, and comparing it with records from East Asia and the central-eastern equatorial Pacific, enabled the researchers to pinpoint century-scale patterns in Pacific rainfall and temperature, and link them with global climate changes in the past 2000 years. Continue reading “Mega-scale El Niña pattern may have big climate impacts”

Climate: Is this year’s El Niño here to stay?

Forecasters nearly certain pattern will persist at least through the end of summer and probably to the end of the year

Warm sea surface temperatures along the equatorial Pacific show the shape of El Niño.
A classic El Niño sea surface temperature pattern is projected in this map from NOAA.

By Bob Berwyn

FRISCO — A developing Pacific El Niño is already affecting weather patterns across the western U.S. by bringing abundant spring moisture to the region, including late season snow and rain to parts of parched California.

And last week meteorologists with the National Oceanic and Atmospheric Administration said El Niño is likely to stick around for the summer and probably even through the end of the year, perhaps even gaining strength. More on the forecast in this NOAA El Niño blog.
Continue reading “Climate: Is this year’s El Niño here to stay?”

Study eyes Pacific warm water ‘blob’ as drought driver

‘This is a taste of what the ocean will be like in future decades’

Exceedingly high water temperatures in the eastern Pacific have persisted for several years, influencing weather across western North America and beyond.

Staff Report

FRISCO — Climate scientists have long known that the West has experienced significant long-term droughts during past millennia, but they don’t know exactly why. Understanding the cause may be more important now, given the huge impacts of the current drought in California, so researchers have been focusing on a huge mass of warm water hugging the West Coast.

Those conditions may be linked with a relatively unknown decadal weather pattern called the North Pacific Mode, which may be a significant weather driver, along with the El Niño-La Niño oscillation, and the Pacific Decadal Oscillation, according to the University of Washington’s Dennis Hartmann. Continue reading “Study eyes Pacific warm water ‘blob’ as drought driver”

Climate: Does La Niña increase the odds of tornadoes?

Finding a signal amidst the climate noise isn’t easy

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?”

Climate study predicts doubling of extreme La Niñas

Will global warming intensify extreme weather swings?

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”

New series of climate studies aim to pinpoint global warming impacts on key natural resources

Glen Canyon Dam. Photo via U.S. Bureau of Reclamation.

Arizona researchers to focus on Colorado River flows as feds grant $7 million for 50-plus research projects

By Summit Voice

FRISCO — Arizona-based researchers will lead an effort to pinpoint how global warming will affect Colorado River flows in the coming decades, with an eye toward exploring links between Pacific Ocean climate patterns like El Niño/La Niña cycles and the occurrence of extreme wet or dry conditions.

The two-year study will result in a streamflow projection product that better accounts for physical mechanisms of weather and climate on a regional and local scale, that can be directly used by water resource providers.

The research project is one more than 50 studies funded by grants from the U.S. Department of Interior’s regional climate centers as part of President Obama’s Climate Action Plan to reduce carbon pollution, move the economy toward clean energy sources and begin to prepare communities for the impacts of climate change. Continue reading “New series of climate studies aim to pinpoint global warming impacts on key natural resources”