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.
NASA to Investigate Impacts of Arctic Sea Ice Loss
A new NASA field campaign will begin flights over the Arctic this summer to study the effect of sea ice retreat on Arctic climate. The Arctic Radiation IceBridge Sea and Ice Experiment (ARISE) will conduct research flights Aug. 28 through Oct. 1, covering the peak of summer sea ice melt.
ARISE is NASA’s first Arctic airborne campaign designed to take simultaneous measurements of ice, clouds and the levels of incoming and outgoing radiation, the balance of which determines the degree of climate warming. The campaign team will fly aboard NASA’s C-130 aircraft from Thule Air Base in northern Greenland the first week and from Eielson Air Force Base near Fairbanks, Alaska, through the remainder of the campaign.
More than two-thirds of the recent rapid melting of the world’s glaciers can be blamed on humans, a new study finds.
Scientists looking at glacier melt since 1851 didn’t see a human fingerprint until about the middle of the 20th century. Even then only one-quarter of the warming wasn’t from natural causes. But since 1991, about 69 percent of the rapidly increasing melt was man-made, said Ben Marzeion, a climate scientist at the Univ. of Innsbruck.
A group from the Univ. of Alcalá in Spain has defined the landscape of forest fires on a nationwide scale over the course of 42 years. The research has found that the abandonment of agricultural land and higher temperatures have contributed to intensifying the fires.
For the very first time, research has shown how forest fires in Spain have evolved over recent years from 1968 to 2010. The research has been published in the journal Environmental Science and Policy.
The study’s main findings reflect the fact that, in broad terms, an increase in both the number of fires and the burned area was recorded in the 1970s. In 1990 there was a drop in the Mediterranean region that spread to the rest of the territory in the vegetative season, from May to November.
Dusty air blowing across the Pacific from Asia and Africa plays a critical role in precipitation patterns throughout the drought-stricken western U.S. Today, a scientist is presenting new research suggesting that the exact chemical make-up of that dust, including microbes found in it, is the key to how much rain and snow falls from clouds throughout the region. This information could help better predict rain events, as well as explain how air pollution from a variety of sources influences regional climate in general.
She will present a talk on how aerosols impact clouds and climate at the 248th National Meeting & Exposition of the American Chemical Society (ACS).
Kellogg announced today that it will step up efforts to reduce planet-warming emissions in its supply chain as part of a broader initiative designed to be more environmentally friendly.
Under the plan, the Battle Creek-based food products manufacturer will require key suppliers such as farms and mills to measure and publicly disclose their greenhouse gas outputs and targets for reducing them. The company said it will report annually on those emissions and include climate and deforestation policies in the company’s code of conduct for suppliers.
Top environmental regulators for four Republican presidents told Congress this week what many Republican lawmakers won’t: action is needed on global warming.
In a congressional hearing organized to undermine Republican opposition to President Barack Obama’s environmental proposals, Senate Democrats asked the heads of the Environmental Protection Agency for Richard Nixon, George H.W. Bush, George W. Bush and Ronald Reagan to discuss the risks from climate change and what should be done about it. Some Republicans dispute the science of climate change and have worked to unravel Obama’s steps to address it.
Action on Capitol Hill — where even a bland, bipartisan energy efficiency bill couldn’t get passed in May — has been in a deep freeze.
A study of how penguin populations have changed over the last 30,000 years has shown that between the last ice age and up to around 1,000 years ago penguin populations benefited from climate warming and retreating ice. This suggests that recent declines in penguins may be because ice is now retreating too far or too fast.
An international team, led by scientists from the Universities of Southampton and Oxford, has used a genetic technique to estimate when current genetic diversity arose in penguins and to recreate past population sizes. Looking at the 30,000 years before human activity impacted the climate, as Antarctica gradually warmed, they found that three species of penguin; Chinstrap, Adélie and southern populations of Gentoo penguins increased in numbers. In contrast, Gentoo penguins on the Falkland Islands were relatively stable, as they were not affected by large changes in ice extent.