Greenland More Vulnerable to Climate Change than Thought
A new model developed by researchers at the Univ. of Cambridge has shown that despite its apparent stability, the massive ice sheet covering most of Greenland is more sensitive to climate change than earlier estimates have suggested, which would accelerate the rising sea levels that threaten coastal communities worldwide.
In addition to assessing the impact of the increasing levels of melt water created and spilled into the ocean each year as the climate continues to warm, the new model also takes into account the role that the soft, spongy ground beneath the ice sheet plays in its changing dynamics.
Scientists looking at 16 cases of wild weather around the world last year see the fingerprints of man-made global warming on more than half of them.
Researchers found that climate change increased the odds of nine extremes: heat waves in Australia, Europe, China, Japan and Korea, intense rain in parts of the U.S. and India and severe droughts in California and New Zealand. The California drought, though, comes with an asterisk.
Scientists have found amphibians worldwide are breeding earlier because of climate change, but how that affects species is just now being answered.
After warmer winters, wood frogs breed earlier and produce fewer eggs, a Case Western Reserve Univ. researcher has found. Michael Benard, the George B. Mayer Chair in Urban and Environmental Studies and assistant professor of biology, also found that frogs produce more eggs during winters with more rain and snow.
Land ice decay at the end of the last five ice ages caused global sea-levels to rise at rates of up to 5.5 meters per century, according to a new study.
An international team of researchers developed a 500,000-year record of sea-level variability, to provide the first account of how quickly sea-level changed during the last five ice age cycles. The results, published in the latest issue of Nature Communications, also found that more than 100 smaller events of sea-level rise took place in between the five major events.
In a forceful appeal for international cooperation on limiting carbon pollution, President Barack Obama warned starkly that the globe’s climate is changing faster than efforts to address it. “Nobody gets a pass,” he declared. “We have to raise our collective ambition.”
Speaking at a United Nations summit, Obama said the U.S. is doing its part and that it will meet its goal to cut carbon pollution 17 percent from 2005 levels by 2020. He also announced modest new U.S. commitments to address climate change overseas. The summit aims to galvanize support for a global climate treaty to be finalized next year.
Ice in Arctic seas shrank this summer to the sixth lowest level in 36 years of monitoring.
The National Snow and Ice Data Center reported this week that the ice reached its seasonal minimum on Sept. 17 of 1.94 million square miles. That’s down a bit from 2013, but not near as low as the record-setting 2012. It is still 19 percent below average.
Bent and tossed by the wind, a field of soybean plants presents a challenge for an Asian lady bug on the hunt for aphids. But what if the air — and the soybeans — were still?
Rising temperatures and shifting precipitation patterns may get the lion’s share of our climate change attention, but predators may want to give some thought to wind, according to a Univ. of Wisconsin-Madison zoologist’s study, which is among the first to demonstrate the way “global stilling” may alter predator-prey relationships.
Earth’s protective ozone layer is beginning to recover, largely because of the phase-out since the 1980s of certain chemicals used in refrigerants and aerosol cans, a U.N. scientific panel reported in a rare piece of good news about the health of the planet.
Scientists said the development demonstrates that when the world comes together, it can counteract a brewing ecological crisis. For the first time in 35 years, scientists were able to confirm a statistically significant and sustained increase in stratospheric ozone, which shields the planet from solar radiation that causes skin cancer, crop damage and other problems.
With climate change still a political minefield across the nation despite the strong scientific consensus that it’s happening, some community leaders have hit upon a way of preparing for the potentially severe local consequences without triggering explosions of partisan warfare: just change the subject.
Big cities and small towns are shoring up dams and dikes, using roof gardens to absorb rainwater or upgrading sewage treatment plans to prevent overflows. Others are planting urban forests, providing more shady relief from extreme heat. Extension agents are helping farmers deal with an onslaught of newly arrived crop pests.
But in many places, especially strongholds of conservative politics, they’re planning for the volatile weather linked to rising temperatures by speaking of “sustainability” or “resilience,” while avoiding no-win arguments with skeptics over whether the planet is warming or that human activity is responsible.
Depictions of animals in ancient Egyptian artifacts have helped scientists assemble a detailed record of the large mammals that lived in the Nile Valley over the past 6,000 years. A new analysis of this record shows that species extinctions, probably caused by a drying climate and growing human population in the region, have made the ecosystem progressively less stable.
The study, published in PNAS, found that local extinctions of mammal species led to a steady decline in the stability of the animal communities in the Nile Valley. When there were many species in the community, the loss of any one species had relatively little impact on the functioning of the ecosystem, whereas it is now much more sensitive to perturbations, according to first author Justin Yeakel, who worked on the study as a graduate student at UC Santa Cruz, and is now a postdoctoral fellow at the Santa Fe Institute.
One of the most visible signs of climate change in recent years was not even visible at all until a few decades ago. The sea ice cap that covers the Arctic Ocean has been changing dramatically, especially in the last 15 years. Its ice is thinner and more vulnerable – and at its summer minimum now covers more than 1 million fewer square miles than in the late 1970s. That’s enough missing ice to cover Alaska, California and Texas.
A key part of the story of how the world was able to witness and document this change centers on meticulous work over decades by a small group of scientists at NASA’s Goddard Space Flight Center. Late nights in mainframe rooms, double- and triple-checking computer printouts, processing and re-processing data – until the first-ever accurate atlases of the world’s sea ice were published.
Genetic Signatures May Help Predictive Climate Models
One aspect of the climate change models researchers have been developing looks at how plant ranges might shift, and how factors such as temperature, water availability and light levels might come into play. Forests creeping steadily north and becoming established in the thawing Arctic is just one of the predicted effects of rising global temperatures.
A recent study published in Nature Genetics offers a more in-depth, population-based approach to identifying such mechanisms for adaptation, and describes a method that could be harnessed for developing more accurate predictive climate change models. For the U.S. Department of Energy, which is developing biomass crops for biofuels production, this knowledge could determine which genotypes – genetic makeup of an organism – of biomass crop may thrive better than others in certain environments.
Deep in the hilly grasslands of remote Inner Mongolia, twin smoke stacks rise more than 200 feet into the sky, their steam and sulfur billowing over herds of sheep and cattle. Both day and night, the rumble of this power plant echoes across the ancient steppe, and its acrid stench travels dozens of miles away.
This is the first of more than 60 coal-to-gas plants China wants to build, mostly in remote parts of the country where ethnic minorities have farmed and herded for centuries. Fired up in December, the multibillion-dollar plant bombards millions of tons of coal with water and heat to produce methane, which is piped to Beijing to generate electricity.
It’s part of a controversial energy revolution China hopes will help it churn out desperately needed natural gas and electricity while cleaning up the toxic skies above the country’s eastern cities. However, the plants will also release vast amounts of heat-trapping carbon dioxide, even as the world struggles to curb greenhouse gas emissions and stave off global warming.
A new study from Lund Univ. has, for the first time, reconstructed solar activity during the last ice age. The study shows that the regional climate is influenced by the sun and offers opportunities to better predict future climate conditions in certain regions.
For the first time, a research team has been able to reconstruct the solar activity at the end of the last ice age, around 20,000–10,000 years ago, by analyzing trace elements in ice cores in Greenland and cave formations from China. During the last glacial maximum, Sweden was covered in a thick ice sheet that stretched all the way down to northern Germany and sea levels were more than 100 meters lower than they are today, because the water was frozen in the extensive ice caps. The new study shows that the sun’s variation influences the climate in a similar way regardless of whether the climate is extreme, as during the Ice Age, or as it is today.
Model Predicts Water Scarcity, Climate Change in 2095
What will a global water scarcity map look like in 2095? Radically different, according to scientists at Pacific Northwest National Laboratory, depending on the type and the stringency of the climate mitigation policies chosen to reduce carbon pollution.
In a first of its kind comprehensive analysis, the researchers, working at the Joint Global Change Research Institute, used a unique modeling capability that links economic, energy, land-use and climate systems to show the effects of global change on water scarcity. When they incorporated water use and availability in this powerful engine and ran scenarios of possible climate mitigation policy targets, they found that without any climate policy to curb carbon emissions, half the world will be living under extreme water scarcity. Some climate mitigation policies, such as increasing growth of water-hungry biofuels, may exacerbate water scarcity.