• Gardeners know the frustration of a false spring. Coaxed outside by warm weather, some people plant their gardens in the spring only to see a sudden late frost strike at the plants with a killer freezer burn. Grumbling green thumbs, along with farmers and water supply managers, would benefit from more accurate predictions of the first and last frosts of the season.

    Such timing is in flux, however. The frost-free season in North America is approximately 10 days longer now than it was a century ago. In a new study, published today in Nature Communications, researchers from the University of Utah and the U.S. Geological Survey parse the factors contributing to the timing of frost in the United States. Atmospheric circulation patterns, they found, were the dominant influence on frost timing, although the trend of globally warming temperatures played a part as well.

  • A team of researchers from four American universities says the key to reducing harmful greenhouse gases (GHG) in the short term is more likely to be found on the dinner plate than at the gas pump.

    The team, headed by Loma Linda University (LLU) researcher Helen Harwatt, PhD, suggests that one simple change in American eating habits would have a large impact on the environment: if Americans would eat beans instead of beef, the United States would immediately realize approximately 50 to 75 percent of its GHG reduction targets for the year 2020.

  • Over the week of May 15, extreme rainfall drenched northeastern Australia and NASA data provided a look at the record totals.

    The rainfall was the heaviest rainfall in that area since tropical cyclone Debbie hit Queensland Australia in late March. Much of the recent extremely heavy rainfall was due to storms associated with a trough or elongated area of low pressure slowly moving over northeastern Queensland from the Coral Sea. More than 100 millimeters or 3.9 inches of rain in 24 hours was reported near Townsville. A trough of low pressure that moved eastward from central Australia was also encroaching into western Queensland.   

  • Falling sulfur dioxide emissions in the United States are expected to substantially increase rainfall in Africa’s semi-arid Sahel, while bringing slightly more rain to much of the U.S., according to a new study in the Journal of Geophysical Research: Atmospheres.

    Pollution filters placed on coal-fired power plants in the United States starting in the 1970s have dramatically cut emissions of sulfur dioxide, a toxic gas that contributes to acid rain and premature deaths from respiratory and cardiovascular diseases. If U.S. sulfur dioxide emissions are cut to zero by 2100, as some researchers have projected, rainfall over the Sahel could increase up to 10 percent from 2000 levels, computer simulations published in the study suggest.

  • The wildfire that has raged across more than 150,000 acres of the Okefenokee Swamp in Georgia and Florida has sent smoke billowing into the sky as far as the eye can see. Now, new research published by the Georgia Institute of Technology shows how that smoke could impact the atmosphere and climate much more than previously thought.

    Researchers have found that carbon particles released into the air from burning trees and other organic matter are much more likely than previously thought to travel to the upper levels of the atmosphere, where they can interfere with rays from the sun – sometimes cooling the air and at other times warming it.

  • A NASA-funded field campaign getting underway in Florida on May 25 has a real shot at improving meteorologists' ability to answer some of the most fundamental questions about weather: Where will it rain? When? How much?

    Called the Convective Processes Experiment (CPEX), the campaign is using NASA's DC-8 airborne laboratory outfitted with five complementary research instruments designed and developed at NASA. The plane also will carry small sensors called dropsondes that are dropped from the plane and make measurements as they fall. Working together, the instruments will collect detailed data on wind, temperature and humidity in the air below the plane during the birth, growth and decay of convective clouds -- clouds formed by warm, moist air rising off the subtropical waters around Florida.

  • Although computer models of archaeological sites are commonly used to yield insights which contribute to the protection of heritage materials, scientists often question their credibility, calling for these long-term trends be 'ground truthed' in order to ensure that calculated rates of change reflect observed phenomena ‘in the field’.  This is particularly true in areas which tend to experience more pronounced and cumulative impacts of modern climate change.

    A recent study by Michael J. E. O’Rourke from the University of Toronto, published in Open Archaeology, provides a new perspective on the severe impacts of escalating climate change on the heritage resources of Canadian Arctic.  Referring to the application of Geographic Information System (GIS) analytical methods in assessing the threat of shoreline erosion to archaeological sites in the Canadian Arctic, it details steps taken to review the quality of the GIS model in light of a discrepancy with rates observed during annual survey visits.

  • The frequency and severity of coastal flooding throughout the world will increase rapidly and eventually double in frequency over the coming decades even with only moderate amounts of sea level rise, according to a new study released today in “Nature Scientific Reports.”

    This increase in flooding will be greatest and most damaging in tropical regions, impairing the economies of coastal cities and the habitability of low-lying Pacific island nations. Many of the world's largest populated low-lying deltas (such as the Ganges, Indus, Yangtze, Mekong and Irrawaddy Rivers), also fall in or near this affected tropical region.

  • A new study from researchers at UCLA and the University of Houston reveals estimates of significant groundwater loss in California’s Central Valley during the recent drought and sparks questions of sustainability for the important agricultural area.

  • Growing plants and then storing the CO2 they have taken up from the atmosphere is no viable option to counteract unmitigated emissions from fossil fuel burning, a new study shows. The plantations would need to be so large, they would eliminate most natural ecosystems or reduce food production if implemented as a late-regret option in the case of substantial failure to reduce emissions. However, growing biomass soon in well-selected places with increased irrigation or fertilization could support climate policies of rapid and strong emission cuts to achieve climate stabilization below 2 degrees Celsius.