Category: El Niño

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.

New surveys confirm Great Barrier Reef damage

Heat-driven coral bleaching continues to take a toll

Staff Report

A new survey of the Great Barrier Reef shows that an ocean heat wave that peaked last March killed up to 95 percent of corals in some parts of the northern reef.  And in the aftermath of the worst coral-bleaching event on record, predatory snails are now taking on toll on the remaining corals.

According to the ARC Centre of Excellence for Coral Reef Studies, researchers recently returned to 83 reefs they surveyed at the height of the bleaching event.

“Millions of corals in the north of the Great Barrier Reef died quickly from heat stress in March and since then, many more have died more slowly,” said Dr. Greg Torda whose team recently returned from re-surveying reefs near Lizard Island. Continue reading “New surveys confirm Great Barrier Reef damage”

How will Antarctica respond to global warming?

Long-term studies show potential impacts of climate change

Antarctic biodiversity is at risk from climate change. Photo by Bob Berwyn.
Antarctic ecosystems are at risk from climate change. @bberwyn photo.

Staff Report

A new set of scientific reports highlights the value of long-term observations in relatively undisturbed ecosystems and also offers a preview of how global warming may change Antarctica in coming decades.

The research shows that a period of unusual warmth in 2001 and 2002, caused by a confluence two natural climate cycles,  accelerated the microbial food chain and shook up the distribution of penguin populations and thinned glaciers according to October issue of the journal BioScience .

The research came out of two long-term ecological research stations, including Palmer Station, on the West Antarctic Peninsula, where scientists study how “changing sea ice extent influences marine ecology and the multilayered food webs of the coastal, nearshore, and continental slope ecosystems.” Other studies were done at the  McMurdo Dry Valleys LTER, in an ice-free polar desert where glacial meltwater plays a huge role in ecosystems. Continue reading “How will Antarctica respond to global warming?”

New study tracks origins of the Pacific ‘ warm blob’

El Niño a key factor, but global warming to increase marine heatwaves

Marine heatwaves are becoming more frequent and widespread.
Marine heatwaves are becoming more frequent and widespread.

Staff Report

A disruptive ocean heatwave in the northeastern Pacific Ocean in 2014 and 2015 was probably a manifestation of El Niño, says a new study by scientists with the Georgia Institute of Technology and the National Oceanic and Atmospheric Administration (NOAA).

Such warm-water events could become more common as heat-trapping pollution continues to increase in the atmosphere, according to the findings published in the journal Nature Climate Change. Continue reading “New study tracks origins of the Pacific ‘ warm blob’”

Bleaching risk on the rise for Great Barrier Reef corals

Global warming is likely to overwhelm corals'
Global warming is likely to overwhelm corals’ built-in thermal tolerance mechanisms within the next few decades, leading to more bleaching and mortality. Photo courtesy Dr. Peter Mumby.

Study identifies bleaching and mortality thresholds for imperiled coral reefs

Staff Report

The steady rise in ocean temperatures projected for the next few decades will put more and more corals at risk of bleaching, as the warm water simply overwhelms their thermal tolerance mechanisms.

Recent research along the Great Barrier Reef shows that corals have been able to survive past bleaching events because they were acclimated to warmer temperatures by being exposed to a pattern of gradually warming waters in the lead up to each episode. But global warming is likely to change that, the scientists said.

Before long, temperature increases of as little as 0.5 degrees Celsius may push many corals over the edge as the warm water causes them to expel the algae-like dinoflagellates that help keep them alive and give them their color.

Lead author Dr. Tracy Ainsworth from Coral CoE said  bleaching is like a marathon for corals.

“When corals are exposed to a pre-stress period in the weeks before bleaching, as temperatures start to climb, this acts like a practice run and prepares the coral. Corals that are exposed to this pattern are then less stressed and more tolerant when bleaching does occur,” Ainsworth said. Continue reading “Bleaching risk on the rise for Great Barrier Reef corals”

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”