ocean warming

Record Siberian Heat | Earth Wise

July 24, 2020 By EarthWise Leave a Comment

Siberia has been experiencing unprecedented high temperatures in recent months. May was the hottest May on record and temperatures in Siberia have stayed well above average for the past year.

On June 20, temperatures in the small Siberian town of Verkhoyansk hit 100.4 degrees Fahrenheit, which is a record-high temperature in one of the fastest-warming places in the world. Average high temperatures in June reach 68 degrees. Verkhoyansk sits on the Yana River in the Arctic Circle and, during the winter, is one of the world’s coldest towns. In 1892, its temperature dropped to -90 degrees Fahrenheit. And now there is hundred-degree heat above the Arctic Circle.

Siberia tends to experience large temperature swings month-to-month and year-to year. But it is very unusual for temperatures to stay well over average over an extended period of time as they have for the past year. According to climate scientists, the kind of temperature swings seen recently would only happen once in 100,000 years if it were not for climate change.

Siberia has seen raging wildfires and structural damage from thawing permafrost as its temperatures have stayed warmer than normal. The prolonged Siberian heatwave is an alarming situation.

The Arctic is warming twice as fast as the rest of the Earth because of a process known as Arctic amplification. The acceleration of the Arctic ice melt leads to a seasonal snow cover that isn’t as white. It therefore absorbs more sunlight, which then leads to more warming.

The amplified warming of the Arctic with its increased melting of ice leads to higher sea levels, and not just in the Arctic Ocean. With less Arctic ice to reflect sunlight, the world’s oceans continue to warm.

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Temperatures in an Arctic Siberian town hit 100 degrees, a new high

Photo, posted December 7, 2014, courtesy of Olga Dudenko via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Climate Change And Global Fisheries

April 12, 2019 By EarthWise Leave a Comment

A Rutgers University-led study published in the journal Science has shown that climate change has taken a toll on many of the world’s fisheries and that over fishing has magnified the problem.

Seafood has become an increasingly important source of nourishment as the global population grows, especially in coastal, developing countries where it provides as much as half of the animal protein eaten. More than 50 million people worldwide work in the fisheries industry or subsist on fisheries.

Scientists at Rutgers and the National Oceanic and Atmospheric Administration studied the impact of ocean warming on 235 populations of 124 species in 38 ecological regions around the world. Species included fish, crustaceans such as shrimp, and mollusks such as scallops. They combined data on fisheries with ocean temperature maps to estimate temperature-driven changes in the sustainable catch over 8 decades. The data covered about one-third of the global catch.

According to the study, ocean warming has led to an estimated 4.1% drop in sustainable catches, on average around the world, for many species of fish and shellfish from 1930 to 2010. In five regions that include the East China Sea and the North Sea, the estimated decline was 15 to 35%.

The researchers recommend that fisheries managers eliminate over fishing, rebuild fisheries, and account for climate change in fisheries management decisions. Over fishing provides a one-two punch to fisheries facing warming waters. It not only makes fisheries more vulnerable to ocean warming but continued warming will also hinder efforts to rebuild over fished populations.

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Climate Change Shrinks Many Fisheries Globally, Rutgers-Led Study Finds

Photo, posted April 23, 2011, courtesy of Derek Keats via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

2018 Was A Wet Year

March 20, 2019 By EarthWise Leave a Comment

Recent news reports noted that 2018 was the fourth hottest year on record. But the changing climate is not just about temperature. 2018 was also the third-wettest year since 1895, when steady record-keeping began.

Overall, the U.S. recorded 4.68 inches more precipitation in 2018 than the 20th century average. But all that rain and snow was nothing like evenly distributed. The eastern half of the country – especially in places like North Carolina and Virginia – saw record amounts of precipitation, while most of the West remained stuck in drought.

The warming climate leads to precipitation extremes at both ends, meaning that wet places are likely to get wetter and dry places drier. There has been a marked upward trend in short-duration extreme events. For example, Cyclone Mekunu dumped almost 13 inches of rain on Salalah, Oman in 36 hours, more than double its annual average rainfall.

In the southeast and eastern U.S., the trend toward stronger storm events is mostly driven by strong warming of the oceans that fringe their shores. Warm oceans evaporate more water into the air and warm air holds more water than cooler air. Warmer, moisture-laden air acts like a blanket over the land, keeping heat trapped near the ground. Many of the states that had their wettest-ever years also set records for high minimum temperatures – their coldest temperatures were less cold than in the past.

Air temperatures are projected to warm up even further in the coming years and, as a result, many scientists are anticipating that extreme precipitation events will only get more extreme. The pattern of drought in the west and wetness in the east is likely to stay.

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2018 was the U.S.’s third-wettest year on record—here’s why

Photo, posted August 18, 2018, courtesy of Jim Lukach via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Fewer Snowbird Sharks

April 23, 2018 By EarthWise Leave a Comment

Blacktip sharks are snowbirds, to use a cross-species metaphor. At least, they usually are. The males of the species swim south to southern Florida during the coldest months of the year and head back north to North Carolina in the spring to mate with females.

Could Coral Reefs Be Wiped Out?

August 8, 2017 By EarthWise

A new study warns that coral reefs are in danger of disappearing forever. According to U.N. research, the world’s coral reefs could die out completely by mid-century unless carbon emissions are reduced enough to slow ocean warming.

Threats To Coral Reefs

May 12, 2017 By EarthWise

There has been much news recently about the growing bleaching events going on in the world’s coral reefs associated with ocean warming and acidification. The massive damage to Australia’s Great Barrier Reef is an ongoing tragedy.

Bleached And Dying

February 23, 2017 By EarthWise

Climate change is posing a major threat to the future of coral reefs. According to a recent United Nations-backed study, if swift action is not taken to curb greenhouse gas emissions, annual coral bleaching events will affect nearly all of the world’s coral reefs. And coral bleaching can result in serious coral mortality – as Australia’s Great Barrier Reef has recently illustrated.

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Locked In A Pattern Of Arctic Ice Loss

November 5, 2015 By EarthWise

There is no dry land at the North Pole and under much of the Arctic ice pack. There, the ocean is covered with sea ice. When this ice melts, it does not cause a rise in sea level, the same way ice cubes melting in your water glass don’t cause it to overflow.