Category: El Niño

Changing ocean alters food web

Study documents shifts caused by warming seas, other stressors

A chemical analysis of dolphin skin cells helped scientists track changes in the ocean food chain. @bberwyn photo.

Staff Report

Big fish eat little fish is the conventional wisdom of the sea, but it’s not always quite so simple. When Global warming and El Niño combined in 2015 and 2016 to warm the Pacific Ocean to new record-high temperatures, it shifted the food chain significantly, according to scientists with NOAA, the Moss Landing Marine Laboratories and the Scripps Institution of Oceanography.

According to their new study, published in the journal Science Advances,  the food web “changed in response to various natural and anthropogenic related stressors,” said lead author Rocio I. Ruiz-Cooley, formerly of NOAA Fisheries’ Southwest Fisheries Science Center and now at Moss Landing Marine Laboratories. “This tells us that the food web is very dynamic, and reveals changes with the ecosystem around it.” Continue reading “Changing ocean alters food web”

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Mass coral bleaching likely along northern Great Barrier Reef

Extensive stand of severely bleached coral at Lisianski Island in the Papahanaumokuakea Marine National Monument in Hawaii, documented during an August 2014 NOAA research mission. (Credit: NOAA).

Scientists are currently mapping the biological damage caused by global warming

Staff Report

At the end of eastern Australia’s long, hot summer, ocean scientists are once again seeing devastating coral die-backs in the northern reaches of the Great Barrier Reef. Over the next few weeks, they’ll venture underwater to study how the coral communities responded to a second straight year of overheated water.

When temperatures pass a threshold, the coral expels its symbiotic algal partner, leaving underwater wastelands of white-washed reefs. The scientists will also use survey flights above the reef, and even satellite imaging as they mobilize to document one of global warming’s most devastating impacts. There has been a prolonged global mass bleaching under way for the past year, and climate researchers say nearly all the world’s corals will be at risk by mid-century under projected global temperature increases. Continue reading “Mass coral bleaching likely along northern Great Barrier Reef”

Coral bleaching threat persists in Southern Hemisphere

Uptick in tropical cyclones intensifies impacts, hampers recovery

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A recent update from NOAA’s coral watch program shows that many reefs in the Southern Hemisphere face potential bleaching events in the next several months.

Staff Report

Along with the widely reported bleaching threat from over-heated oceans, coral reefs in many parts of the world also may have to cope with intensifying tropical storms, which could make it even more difficult for them to survive the Anthropocene.

New research published in the journal Global Change Biology looked at whether predicted increases in cyclone intensity might change the nature of coral reefs, using the Great Barrier Reef as a test case with reef data going back to 1996, as well as information gathered during recent tropical cycles. The study found that tropical cyclones between 2009 and 2014  caused record destruction of corals. Continue reading “Coral bleaching threat persists in Southern Hemisphere”

USGS study tracks West Coast El Niño erosion

Some of the biggest waves on record took a toll on beaches

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Santa Monica beach during a break from the El Niño storms of 2015-2016. @bberwyn photo.

The  2015-16 El Niño may have been a bust as far as precipitation in California, but it still ended up as one of the strongest episodes of the last 145 years, according to U.S. Geological Survey scientists who studied erosion along the West Coast.

They found that, on average, erosion was  76 percent above normal, with most beaches in California eroded beyond historical extremes. If, as some research suggests, El Niños become stronger in a warming climate, then the West Coast, with its 25 million inhabitants, will become increasingly vulnerable to coastal hazards.

The study covered seasonal changes at 29 beaches from Washington to Southern California. They used 3-D maps and aerial lidar imaging, GPS topographic surveys, and direct measurements of sand levels, combined with wave and water level data to measure the changes.

Winter beach erosion or the removal and loss of sand from the beach is a normal seasonal process, but the extent of erosion can be more severe during El Niño events than in other years.

Continue reading “USGS study tracks West Coast El Niño erosion”

Signs of serious global warming impacts piled up in 2016

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2016 is on track to be the third year in a row with a record-warm average global temperature.

There wasn’t any relief from a wave of worrisome global warming news in the spring of 2016, including a study from Harvard showing how rising temperatures will send ozone levels surging to dangerous highs across parts of the U.S.

“In the coming decades, global climate change will likely cause more heat waves during the summer, which in turn could cause a 70 to 100 percent increase in ozone episodes, depending on the region,” said Lu Shen, first author and graduate student at Harvard’s John A. Paulson School of Engineering and Applied Sciences.

Even if the president-elect follows through on his threat to cut funding for Earth observation programs, there are other international science agencies that will continue to monitor climate change impacts, including the European Space Agency. In April, data from ESA ice-observing instruments showed that the meltdown of Antactic ice shelves may be irreversible at this point. The thick shelves of ice that sit at the edge of the continent act as breaks on inland glaciers. If the ice shelves vanish, it could mark a point of no return for Antarctica’s ice, the ESA reported. Continue reading “Signs of serious global warming impacts piled up in 2016”

October ends up as 3d-warmest for Earth

Year-to-date still on record-breaking pace

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Record warmth has spanned the globe in 2016.

Staff Report

The average global temperature for October 2016 was 1.31 degrees Fahrenheit above the 20th century average, putting the month in a tie with 2003 for the third-warmest October on record.

Including 2016, the past three Octobers have been the three warmest in the historical record, but with the globe cooling down slightly from an El Niño heat surge, the monthly anomaly was the lowest deparature from average since Nov. 2014, according to the latest global monthly state of the climate report from the NOAA National Centers for Environmental Information. Continue reading “October ends up as 3d-warmest for Earth”

Global hot streak continues in October

No let up in global warming spiral, especially in the Arctic

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Surface air temperature anomaly for October 2016 relative to the October average for the period 1981-2010. Source: ERA-Interim. (Credit: ECMWF, Copernicus Climate Change Service)

Staff Report

The average global temperature for October 2016 was 0.57 degrees Celsius above the 1981 to 2010 average, continuing a spell of “exceptional global warmth that has now lasted more than a year, according to the European Climate Change Service.

Global temperature anomalies topped out in February with the peak of El Niño, then declined in spring and rose again in summer, declining only slightly in September. The October departure from normal was only slightly lower in October,  just 0.07 degrees Celsius under the all-time record for the month, set just last year.

With the exception of June, each month from October 2015 to October 2016 has been more extreme than January 2007, which was previously the month with the warmest anomaly. Each month from August 2015 to September 2016 successively became the warmest on record for that particular month.

October 2016 was cooler than the 1981-2010 average over much of Europe, but warmer than average in the far north of the continent and over the Iberian Peninsula and Mediterranean.  Well-above normal temperatures also occurred over the USA and parts of Africa. Temperatures were most above normal over much of the Arctic and Antarctic, with record-low sea extent in both regions.

Temperatures were below average along the equator over the eastern Pacific Ocean, indicating weak La Niña conditions, over some oceanic regions of the southern hemisphere and over part of the North Atlantic. Other land areas with below-average temperatures include most of Australia, western and north-eastern Canada and much of the southern half of South America. The zone of below-average temperatures bounded north and south by above-average temperatures extended eastwards across Asia.

Averaging over twelve-month periods smooths out the shorter-term variations. Globally, the warmest twelve-month period on record is from October 2015 to September 2016, with a temperature 0.64 degrees Celsius above the 1981-2010 average.

Uncertainty in the global value is relatively high for the year 2005, but there is agreement between various datasets regarding:

  • the exceptional warmth of 2016, and to a lesser extent 2015;
  • the overall rate of warming since the late 1970s;
  • the sustained period of above-average values from 2001 onwards.

There is more variability in average European temperatures, but values are less uncertain because observational coverage of the continent is relatively dense. Twelve-month averages for Europe have been at a persistently high level for the last three years or so. They are nevertheless lower than the averages from around the middle of 2006 to the middle of 2007.