The Northeast Pacific's largest marine heatwave on record was at least in part caused by El Niño climate patterns. And unusually warm water events in that ocean could potentially become more frequent with rising levels of greenhouse gases.
That's the findings of a new study by researchers from Georgia Institute of Technology and the National Oceanic and Atmospheric Administration. They linked the 2014-2015 marine heatwave - often referred to as the "warm blob" - to weather patterns that started in late 2013. The heatwave caused marine animals to stray far outside of their normal habitats, disrupting ecosystems and leading to massive die-offs of seabirds, whales and sea lions.
The study, which was published July 11 in journal Nature Climate Change, was sponsored by the National Science Foundation.
"We had two and a half years of consistent warming, which translated to a record harmful algal bloom in 2015 and prolonged stress on the ecosystem," said Emanuele Di Lorenzo, a professor in Georgia Tech's School of Earth and Atmospheric Sciences. "What we do in the study is ask whether this type of activity is going to become more frequent with greenhouse gases rising."
The researchers traced the origin of the marine heat wave to a few months during late 2013 and early 2014, when a ridge of high pressure led to much weaker winds that normally bring cold Artic air over the North Pacific. That allowed ocean temperatures to rise a few degrees above average.
Then, in mid-2014 the tropical weather pattern El Niño intensified the warming throughout the Pacific. The warm temperatures lingered through the end of the year, and by 2015 the region of warm water had expanded to the West Coast, where algal blooms closed fisheries for clams and Dungeness crab.
"The bottom line is that El Niño had a hand in this even though we're talking about very long-distance influences," said Nate Mantua, a research scientist at NOAA Fisheries' Southwest Fisheries Science Center and a coauthor of the study.
The researchers used climate model simulations to show the connection between increasing greenhouse gas concentrations and the impact on the ocean water temperatures. The study found that these extreme weather events could become more frequent and pronounced as the climate warms.
"This multi-year event caused extensive impacts on marine life," Di Lorenzo said. "For example, some salmon populations have life cycles of three years, so the marine heatwave has brought a poor feeding, growth and survival environment in the ocean for multiple generations. Events like this contribute to reducing species diversity."
And the effects of the "warm blob" could linger.
"Some of these effects are still ongoing and not fully understood because of the prolonged character of the ocean heatwave," Di Lorenzo said. "Whether these multi-year climate extremes will become more frequent under greenhouse forcing is a key question for scientists, resource managers and society."
This material is based upon work supported by the National Science Foundation under Grant Nos. OCE 1356924 and OCE 1419292. Any opinions, findings, and conclusions or recommendations expressed in this material are those of the authors and do not necessarily reflect the views of the National Science Foundation.
CITATION: Emanuele Di Lorenzo and Nathan Mantua, "Multi-year persistence of the 2014/15 North Pacific marine heatwave," (Nature Climate Change, July 2016).
Josh Brown | EurekAlert!
Greenland ice flow likely to speed up: New data assert glaciers move over sediment, which gets more slippery as it gets wetter
17.08.2017 | Swansea University
Climate change: In their old age, trees still accumulate large quantities of carbon
17.08.2017 | Universität Hamburg
Whether you call it effervescent, fizzy, or sparkling, carbonated water is making a comeback as a beverage. Aside from quenching thirst, researchers at the University of Illinois at Urbana-Champaign have discovered a new use for these "bubbly" concoctions that will have major impact on the manufacturer of the world's thinnest, flattest, and one most useful materials -- graphene.
As graphene's popularity grows as an advanced "wonder" material, the speed and quality at which it can be manufactured will be paramount. With that in mind,...
Physicists at the University of Bonn have managed to create optical hollows and more complex patterns into which the light of a Bose-Einstein condensate flows. The creation of such highly low-loss structures for light is a prerequisite for complex light circuits, such as for quantum information processing for a new generation of computers. The researchers are now presenting their results in the journal Nature Photonics.
Light particles (photons) occur as tiny, indivisible portions. Many thousands of these light portions can be merged to form a single super-photon if they are...
For the first time, scientists have shown that circular RNA is linked to brain function. When a RNA molecule called Cdr1as was deleted from the genome of mice, the animals had problems filtering out unnecessary information – like patients suffering from neuropsychiatric disorders.
While hundreds of circular RNAs (circRNAs) are abundant in mammalian brains, one big question has remained unanswered: What are they actually good for? In the...
An experimental small satellite has successfully collected and delivered data on a key measurement for predicting changes in Earth's climate.
The Radiometer Assessment using Vertically Aligned Nanotubes (RAVAN) CubeSat was launched into low-Earth orbit on Nov. 11, 2016, in order to test new...
A study led by scientists of the Max Planck Institute for the Structure and Dynamics of Matter (MPSD) at the Center for Free-Electron Laser Science in Hamburg presents evidence of the coexistence of superconductivity and “charge-density-waves” in compounds of the poorly-studied family of bismuthates. This observation opens up new perspectives for a deeper understanding of the phenomenon of high-temperature superconductivity, a topic which is at the core of condensed matter research since more than 30 years. The paper by Nicoletti et al has been published in the PNAS.
Since the beginning of the 20th century, superconductivity had been observed in some metals at temperatures only a few degrees above the absolute zero (minus...
16.08.2017 | Event News
04.08.2017 | Event News
26.07.2017 | Event News
18.08.2017 | Life Sciences
18.08.2017 | Physics and Astronomy
18.08.2017 | Materials Sciences