Pacific Ocean ENSO cycle a key player in global climate
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.
New findings help sharpen global warming projections
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.
Forecasters nearly certain pattern will persist at least through the end of summer and probably to the end of the year
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.
‘This is a taste of what the ocean will be like in future decades’
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”→
Finding a signal amidst the climate noise isn’t easy
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.
Will global warming intensify extreme weather swings?
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 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.