Tag: sea level

What’s the tipping point for Antarctica’s ice sheets?

New study suggests rapid meltdown during post-ice age warming

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How long will it take for Antarctica’s ice sheets to melt? @bberwyn photo.

Staff Report

After taking a close look at rocks from West Antarctica’s dramatic Ellsworth Mountains, climate researchers say there’s a chance that ice sheets in the region could melt quickly as the planet warms, potentially causing sea level to rise by  six to eight feet.

The new study, published in Nature Communications, took a close look at Antarctic climate change about 21,000 years ago during a period of warming after the coldest point of the most recent Ice Age. They found that  the West Antarctic Ice Sheet reached a tipping point, after which it thinned relatively quickly, losing 400m of thickness in 3,000 years. Continue reading “What’s the tipping point for Antarctica’s ice sheets?”

Annual atmospheric CO2 increase the biggest on record

Far, far away from 350 ppm …

Atmospheric carbon dioxide in February 2016 measured at Mauna Loa.
Atmospheric carbon dioxide in February 2016 measured at Mauna Loa.

Staff Report

The goal of limiting atmospheric carbon dioxide to 350 parts per million — considered the environmentally “safe” level, just moved a little farther away. Scientists tracking concentrations of the heat-trapping pollutant at a mountaintop lab in Hawaii said last week that CO2 concentrations jumped by the largest annual amount recorded since measurements began 56 years ago.

The reading comes from NOAA’s Mauna Loa Observatory, and researchers said the latest increase was the fourth year in a row that CO2 concentrations grew by more than 2 parts per million, according to a press release from NOAA.

“Carbon dioxide levels are increasing faster than they have in hundreds of thousands of years,” said Pieter Tans, lead scientist of NOAA’s Global Greenhouse Gas Reference Network. “It’s explosive compared to natural processes.” Continue reading “Annual atmospheric CO2 increase the biggest on record”

Climate: Land areas storing more water, slowing sea level rise

Study pinpoints changes in global hydrological cycle
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Some low lying coastal areas are already facing more frequent floods as global sea level rises. @bberwyn photo.
This graph shows cumulative changes in sea level for the world’s oceans since 1880, based on a combination of long-term tide gauge measurements and recent satellite measurements. Graph courtesy EPA.
This graph shows cumulative changes in sea level for the world’s oceans since 1880, based on a combination of long-term tide gauge measurements and recent satellite measurements. Graph courtesy EPA.

Staff Report

As crucial as it is for the future of humanity, calculating the rate of sea level rise has never been easy, and new measurements by NASA satellites have added a new twist to the equation. Careful study of the data from NASA’s twin NASA’s Gravity Recovery and Climate Experiment (GRACE) satellites helped show how climate-driven increases of liquid water storage on land have affected the rate of sea level rise.

In the past decade, Earth’s land masses have soaked up an extra 3.2 trillion tons of water in soils, lakes and underground aquifers, temporarily slowing the rate of sea level rise by about 20 percent, according to the new study published in Science.  But that doesn’t mean it’s time to stop worrying — by most projections, rising seas will swamp many coastal cities where millions of people live in the near future. Continue reading “Climate: Land areas storing more water, slowing sea level rise”

Climate: One more thing to worry about?

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Ongoing studies are detailing how melting ice sheets will affect sea level.

Eastern Greenland changes could threaten critical ocean current

By Bob Berwyn

The global climate agreement reached late last year in Paris isn’t going to stop the Greenland Ice Sheet from melting anytime soon. Even with an immediate halt to greenhouse gas emissions. there may be centuries more melting ahead, according to climate scientists.

And the meltdown could be more widespread than previously thought, according to National Snow and Ice Data Center scientist Lora Koenig, who gave an update on the latest research during this week’s Glen Gerberg Weather and Climate Summit in Breckenridge. Continue reading “Climate: One more thing to worry about?”

Climate: Howling Antarctic winds found to ‘eat’ snow

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New data is changing the understanding of the water cycle in Antarctica. @bberwyn photo.

Climate models may need revamping after scientists measure snow loss

Staff Report

Winds howling across the vast, frozen Antarctic plateaus are scouring the region of moisture by vaporizing most of the airborne snow, scientists said in a new study that could shift estimates of how much the ice-covered continent is contributing to sea level rise. Continue reading “Climate: Howling Antarctic winds found to ‘eat’ snow”

Study IDs Gulf Coast ecosystems at risk

Sea turtles as most vulnerable species

Gulf Coast sunset.
Rising sea level and warming ocean temps are putting Gulf Coast ecosystems at risk, according to a new study. @bberwyn photo.

Staff Report

Sea turtles breeding along the Gulf Coast are among the species deemed most vulnerable to climate change and rising sea level, the U.S. Fish and Wildlife Service concluded in a new vulnerability assessment that looked at four Gulf ecosystems and 11 species dependent on them.

The ecosystems are mangrove, oyster reef, tidal emergent marsh and barrier islands. The species are roseate spoonbill, blue crab, clapper rail, mottled duck, spotted seatrout, eastern oyster, American oystercatcher, red drum, black skimmer, Kemp’s ridley sea turtle and Wilson’s plover.

Kemp’s ridley sea turtle is thought to be the most vulnerable species across the Gulf Coast. The report identified the main threat as loss of nesting habitat to sea level rise, erosion, and urbanization. Continue reading “Study IDs Gulf Coast ecosystems at risk”

Pacific islands face extreme sea level changes

Study tracks El Niño shifts

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How will climate change affect Pacific atolls? Photo via NASA.

Staff Report

Climate change will likely subject many low-lying Pacific island nations to more extreme fluctuations in sea level from year to year, in synch with more intense El Niño cycles. Some years, high sea level will lead to bigger floods, while in other years, big drops in sea level will leave coral reefs exposed, according to researchers based in Hawaii and Australia. Continue reading “Pacific islands face extreme sea level changes”