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01.31.12 By Alan Buis, Jet Propulsion Laboratory Two years ago, scientists at the National Center for Atmospheric Research in Boulder, Colo., released a study claiming that inconsistencies between satellite observations of Earth's heat and measurements of ocean heating amounted to evidence of "missing energy" in the planet's system. Where was it going? Or, they wondered, was something wrong with the way researchers tracked energy as it was absorbed from the sun and emitted back into space? An international team of atmospheric scientists and oceanographers, led by Norman Loeb of NASA's Langley Research Center in Hampton, Va., and including Graeme Stephens of NASA's Jet Propulsion Laboratory in Pasadena, Calif., set out to investigate the mystery. They used 10 years of data—spanning 2001 to 2010—from NASA Langley's orbiting Clouds and the Earth's Radiant Energy System Experiment (CERES) instruments to measure changes in the net radiation balance at the t...

02.01.12 By Adam Voiland, NASA's Earth Science News Team A new NASA study underscores the fact that greenhouse gases generated by human activity—not changes in solar activity—are the primary force driving global warming. The study offers an updated calculation of the Earth's energy imbalance, the difference between the amount of solar energy absorbed by Earth's surface and the amount returned to space as heat. The researchers' calculations show that, despite unusually low solar activity between 2005 and 2010, the planet continued to absorb more energy than it returned to space. A prolonged solar minimum left the sun's surface nearly free of sunspots and accompanying bright areas called faculae between 2005 and 2010. Total solar irradiance declined slightly as a result, but the Earth continued to absorb more energy than it emit throughout the minimum. An animation of a full solar cycle is available here. Credit: NASA Goddard's Scientific Visualization Studio Jame...

The doors are open on NASA's Suomi NPP satellite and the newest version of the Clouds and the Earth's Radiant Energy System (CERES) instrument is scanning Earth for the first time, helping to assure continued availability of measurements of the energy leaving the Earth-atmosphere system. The CERES results help scientists to determine the Earth's energy balance, providing a long-term record of this crucial environmental parameter that will be consistent with those of its predecessors. Thick cloud cover tends to reflect a large amount of incoming solar energy back to space (blue/green/white image), but at the same time, reduce the amount of outgoing heat lost to space (red/blue/orange image). Contrast the areas that do not have cloud cover (darker colored regions) to get a sense for how much impact the clouds have on incoming and outgoing energy. Credit: NASA/NOAA/CERES Team *** Click either image to enlarge it *** In the longwave image, heat energy radiated from Earth (in w...

02.08.12 By Alan Buis, Jet Propulsion Laboratory Steve Cole, NASA Headquarters In the first comprehensive satellite study of its kind, a University of Colorado at Boulder-led team used NASA data to calculate how much Earth's melting land ice is adding to global sea level rise. Using satellite measurements from the NASA/German Aerospace Center Gravity Recovery and Climate Experiment (GRACE), the researchers measured ice loss in all of Earth's land ice between 2003 and 2010, with particular emphasis on glaciers and ice caps outside of Greenland and Antarctica. The total global ice mass lost from Greenland, Antarctica and Earth's glaciers and ice caps during the study period was about 4.3 trillion tons (1,000 cubic miles), adding about 0.5 inches (12 millimeters) to global sea level. That's enough ice to cover the United States 1.5 feet (0.5 meters) deep. "Earth is losing a huge amount of ice to the ocean annually, and these new results will help us answer important q...

02.09.12 By Cynthia O'Carroll, NASA Goddard Space Flight Center, John Leslie, National Oceanic and Atmospheric Administration A powerful new infrared instrument, flying on NASA's newest polar-orbiting satellite, designed to give scientists more refined information about Earth's atmosphere and improve weather forecasts and our understanding of climate, has started sending its data back to Earth. The Cross-track Infrared Sounder (CrIS) joins four other new instruments aboard the Suomi National Polar-orbiting Partnership (NPP) satellite, which NASA launched on Oct. 28, 2011 from Vandenberg Air Force Base in California. The Suomi NPP mission is the bridge between NOAA's Polar Operational Environmental Satellite (POES) and NASA's Earth Observing System satellites and the next-generation Joint Polar Satellite System (JPSS). Since it reached orbit, Suomi NPP and its suite of five instruments are undergoing extensive checkouts before starting regular science observations. S...

02.09.12 By Laura Rocchio, NASA Goddard Space Flight Center Over dinner on R.V. Calypso while anchored on the lee side of Glover’s Reef in Belize, Jacques Cousteau told Phil Dustan that he suspected humans were having a negative impact on coral reefs. Dustan — a young ocean ecologist who had worked in the lush coral reefs of the Caribbean and Sinai Peninsula — found this difficult to believe. It was December 1974. Reef environments provide habitat for hundreds of fish species including the queen angelfish shown here in the Florida Keys National Marine Sanctuary. Credit: Chris Huss. But Cousteau was right. During the following three-plus decades, Dustan, an ocean ecologist and biology professor at the College of Charleston in South Carolina, has witnessed widespread coral reef degradation and bleaching from up close. In the late 1970s Dustan helped build a handheld spectrometer, a tool to measure light given off by the coral. Using his spectrometer, Dustan could look at light reflected ...

02.15.12 By Alan Buis, NASA Jet Propulsion Laboratory While NASA's fleet of Earth science spacecraft — its "eyes on the Earth" — continues to monitor the pulse of our home planet, 2012 is also shaping up to be an extraordinary time for NASA's Airborne Science Program and its Earth system science research initiatives. Multiple aircraft and specialized instruments, including several from JPL, will operate in the United States, Europe, Asia and South America this year in support of studies conducted by NASA and the Earth science community, improving scientists' understanding of our planet. The program maintains a fleet of highly modified aircraft and specialized instruments that can be deployed all over the world for Earth science missions. Researchers use these aircraft and sensors to obtain high-resolution measurements of local phenomena and processes, such as ice sheet thicknesses, precipitation and air quality. These measurements are often combined with global sa...

02.21.12 By Alan Buis, Jet Propulsion Laboratory A NASA-led science team has created an accurate, high-resolution map of the height of Earth's forests. The map will help scientists better understand the role forests play in climate change and how their heights influence wildlife habitats within them, while also helping them quantify the carbon stored in Earth's vegetation. Scientists from NASA's Jet Propulsion Laboratory, Pasadena, Calif.; the University of Maryland, College Park; and Woods Hole Research Center, Falmouth, Mass., created the map using 2.5 million carefully screened, globally distributed laser pulse measurements from space. The light detection and ranging (lidar) data were collected in 2005 by the Geoscience Laser Altimeter System instrument on NASA's Ice, Cloud and land Elevation Satellite (ICESat). Accurate measurements of the height of Earth's forests can improve global efforts to monitor how much carbon they contain, while benefitting studies of f...

02.22.12 By Alan Buis, NASA Jet Propulsion Laboratory Earth's clouds got a little lower — about one percent on average — during the first decade of this century, finds a new study based on NASA satellite data. The results have potential implications for future global climate. Scientists at the University of Auckland in New Zealand analyzed the first 10 years of global cloud-top height measurements (from March 2000 to February 2010) from the Multi-angle Imaging SpectroRadiometer (MISR) instrument on NASA's Terra spacecraft. The study, published recently in the journal Geophysical Research Letters, revealed an overall trend of decreasing cloud height. Global average cloud height declined by around one percent over the decade, or by around 100 to 130 feet (30 to 40 meters). Most of the reduction was due to fewer clouds occurring at very high altitudes. Data from NASA's MISR instrument on NASA's Terra spacecraft show that global average cloud height declined by about 1 perc...

Scientists have come up with an entirely new way to monitor the health of Earth’s plants from space. In work published in Geophysical Research Letters [1], researchers working at NASA’s Jet Propulsion Laboratory (JPL) and in Germany and Japan report on how measurements taken from space can open a whole new window onto the planet’s carbon cycle. Carbon is a building block of life. It is also a key component of our climate. Carbon dioxide — a gas that exists naturally in the air, but is also produced by humans when we burn fossil fuels, drive cars and chop down trees — acts as a thermostat that controls the temperature of the planet. As a “greenhouse gas,” it acts like a blanket that traps heat close to the surface of the Earth. The more carbon dioxide we emit, the more the warming. Since the beginning of the industrial age, carbon dioxide levels have gone up by nearly 40 percent, and the world’s average temperature has risen by about 0.5 degrees Celsius (nearly 1 degree Fahrenheit) as a...