Friday, April 28, 2017
Sea Floor Erosion Causes Coral Reefs to Sink
Five US coral reefs are sinking beneath the waves due to the erosion of the sea floor, robbing coastal communities of their natural storm barrier.
The world’s coral reefs are not just in hot water and under threat from acid attack; they may even be getting out of their depth. New research around five US coral reefs shows that even as sea levels rise, the sea floor around the reefs is being eroded.
And coral growth simply may not be fast enough to keep up, which means that coastal communities in Florida, the Caribbean, and Hawaii could become increasingly at risk from storms, waves and erosion.
The news comes close after revelations that great tracts of Australia’s Great Barrier Reef, like other coral colonies, have been devastated by bleaching, as ocean temperatures rise above the levels that corals – animals that live in symbiosis with algae – can tolerate, and researchers have warned that this could soon be happening to reefs almost everywhere, every year.
Coral under threat
There is already widespread alarm among marine scientists as the seas become measurably more acidic due to an increase in levels of carbon dioxide in the atmosphere, and this too poses a threat to corals everywhere.
But while researchers in the tropics had monitored the living reefs of the surface waters, hardly anybody had paid attention to the sea floor around the reefs.
Now, scientists of the US Geological Survey report in Biogeosciences that – possibly as a consequence of the degradation of the reefs of the Florida Keys, the US Virgin Islands, and the Hawaiian island of Maui – the sea floor is being scoured of sand and sediments, just as sea levels continue to creep to a predicted rise of up to a meter by 2100.
Around Maui, they report, they measured the loss enough sand, rock and shell to fill the Empire State Building in New York 81 times over.
This means that the seas along those coasts have become unexpectedly deep. Since tropical corals depend for nourishment on light photosynthesized by their algal partners at the surface, this raises yet another hazard: if the sea floor is falling at the same time as the seawater ceiling is going up, can corals grow fast enough to keep up?
“Our measurements show that seafloor erosion has already caused water depths to increase to levels not predicted to occur until near the year 2100,” says Kimberly Yates, a biogeochemist at the USGS’s St Petersburg Coastal and Marine Science Center, who led the research.
“At current rates, by 2100 sea floor erosion could increase water depths by two to eight times more than what has been predicted from sea level rise alone.”
Healthy coral reefs are among the richest and most diverse habitats on the planet. They represent an immediate asset to human communities: they underwrite tourism and fisheries, and they deliver protection against storm surge and tsunami for around 200 million people in low-lying coastal communities.
Sea level rise presents a threat to communities along the coasts of all the inhabited continents, and coastal flooding could by 2100 be costing the world $100 trillion a year.
One group has calculated that money spent on protecting and restoring reefs would represent a bargain, at about one-twentieth the cost of artificial breakwaters.
Read more at Sea Floor Erosion Causes Coral Reefs to Sink
And coral growth simply may not be fast enough to keep up, which means that coastal communities in Florida, the Caribbean, and Hawaii could become increasingly at risk from storms, waves and erosion.
The news comes close after revelations that great tracts of Australia’s Great Barrier Reef, like other coral colonies, have been devastated by bleaching, as ocean temperatures rise above the levels that corals – animals that live in symbiosis with algae – can tolerate, and researchers have warned that this could soon be happening to reefs almost everywhere, every year.
Coral under threat
There is already widespread alarm among marine scientists as the seas become measurably more acidic due to an increase in levels of carbon dioxide in the atmosphere, and this too poses a threat to corals everywhere.
But while researchers in the tropics had monitored the living reefs of the surface waters, hardly anybody had paid attention to the sea floor around the reefs.
Now, scientists of the US Geological Survey report in Biogeosciences that – possibly as a consequence of the degradation of the reefs of the Florida Keys, the US Virgin Islands, and the Hawaiian island of Maui – the sea floor is being scoured of sand and sediments, just as sea levels continue to creep to a predicted rise of up to a meter by 2100.
Around Maui, they report, they measured the loss enough sand, rock and shell to fill the Empire State Building in New York 81 times over.
This means that the seas along those coasts have become unexpectedly deep. Since tropical corals depend for nourishment on light photosynthesized by their algal partners at the surface, this raises yet another hazard: if the sea floor is falling at the same time as the seawater ceiling is going up, can corals grow fast enough to keep up?
“Our measurements show that seafloor erosion has already caused water depths to increase to levels not predicted to occur until near the year 2100,” says Kimberly Yates, a biogeochemist at the USGS’s St Petersburg Coastal and Marine Science Center, who led the research.
“At current rates, by 2100 sea floor erosion could increase water depths by two to eight times more than what has been predicted from sea level rise alone.”
Healthy coral reefs are among the richest and most diverse habitats on the planet. They represent an immediate asset to human communities: they underwrite tourism and fisheries, and they deliver protection against storm surge and tsunami for around 200 million people in low-lying coastal communities.
Sea level rise presents a threat to communities along the coasts of all the inhabited continents, and coastal flooding could by 2100 be costing the world $100 trillion a year.
One group has calculated that money spent on protecting and restoring reefs would represent a bargain, at about one-twentieth the cost of artificial breakwaters.
Read more at Sea Floor Erosion Causes Coral Reefs to Sink
The Next March Is All About Climate Change
The march builds on a 2014 landmark event that drew hundreds of thousands to the streets around the globe. Then, the push was for the world to deliver a climate deal, a goal achieved a year later in Paris.
The climate action landscape has changed a lot since then, most notably by the election of President Trump. While some of his policies may be driving people to the streets on Saturday, Paul Getsos, the national march coordinator, said he wasn’t the initial impetus for the march.
“We were ready to be active with the next administration when we thought it was Hillary Clinton,” Getsos said. “Our steering committee was working together (last year) to figure out how to make the next president, who we thought was going to be Clinton, be bigger and bolder on climate.”
Nonetheless, Trump’s election has changed the focus a bit. Organizers and other climate advocates are now trying to prevent the U.S. from backsliding on its recent climate action progress.
The Trump administration has walked back a number of climate policies enacted under President Obama and proposed cutting the budget of a number of climate and energy programs. A number of cabinet members have also expressed views far outside established climate science.
The march is slated for Trump’s 100th day in office. Organizers chose the date because the first 100 days is a measuring stick for the president’s priorities. Executive orders aiming to roll back climate policies are among the few tangible goals Trump can point to.
Read more at The Next March Is All About Climate Change
A New Kind of Street Tree Grows in Newton MA
Along with rising sea levels and increased precipitation, the region is expected to experience more frequent, longer, and hotter heat waves, leading to increased drought risk.
A study released in March by the Woods Hole Research Center predicted that 40 tree species in the eastern United States will not be able to adapt to warming temperatures, including some varieties of birch, maple, fir, and cherry.
Researchers reviewed conditions at national parks and recreational areas in Pennsylvania, New Jersey, Tennessee, and Virginia. While park rangers can fight invasive species and pests, researchers said the underlying causes of climate change need to be addressed.
“We need to cut our fossil fuel emissions and stop warming. There’s no getting around that,” said Woods Hole scientist Brendan Rogers in a statement.
The future of Newton’s urban canopy is being shaped in part nearly 500 miles to the west, at Schichtel’s Nursery in Springville, N.Y. It’s where the city gets many of its trees, and growers there worry that the heat will bring drought, threatening trees like sugar maples, said James Kisker, the nursery’s sales manager.
Kisker said the nursery provides trees for more than 150 American cities, including Milwaukee and Minneapolis, and closer to home, Boston, Lexington, Arlington, and Cambridge.
He compared climate change’s predicted impact on some trees to the harm caused by Dutch elm disease to the American elm decades ago, or the Asian longhorned beetle, which wiped out troves of pines in the United States, including in Worcester.
“We’ve seen this pattern before,” he said.
The nursery has been encouraging city foresters to plant several varieties of trees that can handle drought and pollution, Kisker said. And they should be diverse enough to prevent insects and disease from decimating a community’s trees.
Marc Welch, director of the city’s urban forestry division, said the city’s tree program, which began plantings in 2015, is expected to add a total of 1,100 new trees by the end of 2017.
In addition to beautifying public spaces, he said, they offer shade, clean the air, and reduce stormwater runoff.
Specimens are chosen from among 20 to 30 different varieties, depending on the location. Where trees could bump into power lines, crabapple or cherry are being planted. Taller types — oak, for example — are being added where height won’t be an issue, he said.
“They are one of the few public assets, as they grow, they appreciate in value,” Welch said.
Read more at A New Kind of Street Tree Grows in Newton
Thursday, April 27, 2017
The Clean-Energy Transition Is Powering the U.S. Economy
Companies, states, and cities are all pursuing clean energy and energy efficiency because it makes economic sense. The federal government needs to encourage this innovation, not try to slow it down.
Consider that clean energy is the fastest growing energy sector in the United States. Renewables have accounted for more than half of new U.S. power capacity for the past three years in a row. Thanks to market forces, including falling prices for renewables and relatively low and stable prices for natural gas, the U.S. energy system is getting cleaner.
The drive for clean energy and sustainability is also putting Americans to work. The latest U.S. Department of Energy report shows the solar workforce increased by 25 percent to about 374,000 in 2016, while wind employment increased by 32 percent to about 102,000. Almost 2 million Americans are employed in the design, installation, and manufacture of energy-efficiency products and services. The U.S. nuclear industry directly employs about 50,000, and growing global demand could generate thousands of U.S. industry jobs.
Read more at The Clean-Energy Transition Is Powering the U.S. Economy
American Climate Refugees Could Flee Inland
The population of inland American cities will alter drastically if predictions of dramatic sea level rises by 2100 are correct, new report suggests.
If humans go on burning ever greater volumes of fossil fuel, then dramatic rises in sea levels could turn 13 million US citizens into climate refugees and send them fleeing inland – many of them to Atlanta, Houston, and Phoenix.
This latest study, in Nature Climate Change, builds on an earlier assessment of what could happen in 319 American coastal counties if sea levels rise 1.8 meters by 2100.
American refugees
The calculation at the time was that overall sea level rise could threaten the properties of 13.1 million people. This raised the question: where could they all go?
“We typically think about sea level rise as a coastal issue, but if people are forced to move because their houses become inundated, the migration could affect many landlocked communities as well,” says the study’s author, Mathew Hauer, a population scientist in the Department of Geography at the University of Georgia. He also led the original county-by-county estimates of the numbers at risk.
Worldwide, around 1 billion people live in low-lying coastal zones, and an estimated 180 million are at risk. The latest study is claimed as the first attempt to use mathematical simulations to calculate not just the attrition on the coasts, but the long-term consequences for landlocked communities, which will have to accommodate a new class of incomer: the climate refugee.
In December 2015, more than 195 nations agreed in Paris to attempt to contain global warming to 1.5°C by drastically reducing fossil fuel emissions. But even if such promises are fulfilled, European cities could face sea level rises of more than 50cm (1.6 ft) by 2100, enough to put properties and lives at risk in cases of extreme storms and tidal surges.
Richer populations are assumed to be more likely to invest in coastal defenses and some coastal communities will be less at risk than others, yet the cost of what Dr Hauer calls “adaptive infrastructure” in the US could reach $1 trillion.
But population change is inevitable. Miami, in Florida, could lose 2.5 million residents, and, altogether, nine states could see a population decline in response to a sea level rise of 1.8 meters (5.9 ft). Texas, however, could gain 1.5 million citizens, demonstrating, says Dr Hauer, “that the sheer magnitude of places affected could alter the US population landscape”.
Read more at American Climate Refugees Could Flee Inland
This latest study, in Nature Climate Change, builds on an earlier assessment of what could happen in 319 American coastal counties if sea levels rise 1.8 meters by 2100.
American refugees
The calculation at the time was that overall sea level rise could threaten the properties of 13.1 million people. This raised the question: where could they all go?
“We typically think about sea level rise as a coastal issue, but if people are forced to move because their houses become inundated, the migration could affect many landlocked communities as well,” says the study’s author, Mathew Hauer, a population scientist in the Department of Geography at the University of Georgia. He also led the original county-by-county estimates of the numbers at risk.
Worldwide, around 1 billion people live in low-lying coastal zones, and an estimated 180 million are at risk. The latest study is claimed as the first attempt to use mathematical simulations to calculate not just the attrition on the coasts, but the long-term consequences for landlocked communities, which will have to accommodate a new class of incomer: the climate refugee.
In December 2015, more than 195 nations agreed in Paris to attempt to contain global warming to 1.5°C by drastically reducing fossil fuel emissions. But even if such promises are fulfilled, European cities could face sea level rises of more than 50cm (1.6 ft) by 2100, enough to put properties and lives at risk in cases of extreme storms and tidal surges.
Richer populations are assumed to be more likely to invest in coastal defenses and some coastal communities will be less at risk than others, yet the cost of what Dr Hauer calls “adaptive infrastructure” in the US could reach $1 trillion.
But population change is inevitable. Miami, in Florida, could lose 2.5 million residents, and, altogether, nine states could see a population decline in response to a sea level rise of 1.8 meters (5.9 ft). Texas, however, could gain 1.5 million citizens, demonstrating, says Dr Hauer, “that the sheer magnitude of places affected could alter the US population landscape”.
Read more at American Climate Refugees Could Flee Inland
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