April Climate Science Roundup

The first 100 days of the Trump administration saw unprecedented attacks on science, including — and especially — climate science. But researchers continue to work diligently to understand the risks and effects of climate change. This month’s climate science roundup seeks to arm us all with accurate, effective information so that we can work together to save our planet.

March and year to date were 2nd warmest on record for world

Data from NOAA’s National Centers for Environmental Information show that March 2017 was the second hottest March in the 1880-2018 record, behind last year. This also marks the second-highest first-quarter of the year on record, behind 2016. March also hit several other climate benchmarks, with the average Arctic sea ice extent 7.5 percent below the 1981-2010 average, and the average Antarctic sea ice extent 34.2 percent below that average. The globally-averaged land and sea surface temperatures were also the second highest March temperatures on record, at 3.56 degrees F and 1.28 degree F above average, respectively.

Two-thirds of Great Barrier Reef hit by back-to-back mass coral bleaching

For the second time in 12 months, scientists have recorded severe coral bleaching along the Great Barrier Reef. In 2016, bleaching was most severe in the northern third of the reef, while this year the middle third has experienced the most intense coral bleaching. When stressed by factors like overly-warm water, corals eject the symbiotic algae that provide them with their bright colors and with nutrients. While bleached corals are not necessarily dead, if stressors remain in place for too long, they can die.

The Arctic is warming twice as fast as the rest of the planet

A report compiled by more than 90 scientists documents the myriad changes under way across the Arctic because of climate change. The assessment suggests that the Arctic is warming twice as fast as the rest of the planet, and sea ice and snow cover continue to decline.

Global plant growth surging alongside carbon dioxide

A study published in Nature concludes that as carbon dioxide emissions have increased since the beginning of the 20th century, plants around the world are utilizing 30 percent more carbon dioxide. This has prompted increased plant growth. Tracking this information will help scientists better predict the biosphere’s response to continued greenhouse gas emissions.

Glacier shape influences susceptibility to melting

A NASA-funded study in Nature Geoscience has identified which glaciers in West Greenland are most susceptible to thinning in the coming decades. The Greenland Ice Sheet is the second largest ice sheet on Earth and has been melting due to our warming climate. However, predicting which glacier will melt and when has proven difficult, which in turn makes it challenging to predict the impact of future sea-level rise. By identifying glaciers by shape, including thickness and surface slope, scientists are better able to predict the rate of melting.

Migration induced by sea-level rise could reshape the US population landscape

A new study published in Nature Climate Change models the future of climate change refugees within the United States. The study finds that unmitigated sea-level rise will likely reshape the U.S. population distribution, potentially stressing landlocked areas unprepared to accommodate sudden growth.

Climate change could destroy far more Arctic permafrost than previously thought

A study in Nature Climate Change estimates that climate change could cause 1.5 million square miles of permafrost to disappear with every additional degree Celsius of warming. That’s an area nearly half the size of the United States. This loss of permafrost would likely trigger further warming: as permafrost thaws, it releases methane, a highly potent greenhouse gas that would trap further heat. Thawing permafrost could also damage roads and buildings.

California will need mountains of sand to save its beaches

Without human intervention, many of Southern California’s beaches may disappear by 2100 as sea levels rise. Forecast modeling by researchers from University of Illinois at Chicago and the U.S. Geological Survey predicts that a third to two-thirds of beaches will effectively disappear by the end of the century even if California continues to add sand to the beaches at the current rate. Beaches play an important role in California’s $40 billion annual coastal and ocean economy, and also protect coastal communities from flooding and storms.

California drought may be the worst dry spell in nearly 450 years

October 2011 to September 2015 was the driest four-year period in California since 1895. But not only that; a new study by NOAA’s National Centers for Environmental Information suggests the southern Central Valley and South Coast saw their worst dry spell in nearly 450 years. The study also shows that California’s hardest-hit areas will likely need several decades for their long-term average precipitation to recover back to normal levels. If temperatures continue to rise as they have, this may become the new normal, with the U.S. Southwest facing “megadroughts” by the second half of this century.

Edited by Elizabeth Weinberg. Have a climate science tip? Send it to climate-science@350pdx.org.