Results for: Fact Sheets
The Carbon Cycle
June 16, 2011Carbon flows between the atmosphere, land, and ocean in a cycle that encompasses nearly all life and sets the thermostat for Earth's climate. By burning fossil fuels, people are changing the carbon cycle with far-reaching consequences. Read more
Aerosols: Tiny Particles, Big Impact
November 2, 2010Tiny aerosol particles can be found over oceans, deserts, mountains, forests, ice sheets, and every ecosystem in between. They drift in the air from the stratosphere to the surface. Despite their small size, they have major impacts on our climate and our health. Read more
The Water Cycle
October 1, 2010Landscape sculptor. Climate driver. Life supporter. Water is the most important molecule on our planet. Read more
What are Phytoplankton?
July 16, 2010Microscopic plant-like organisms called phytoplankton are the base of the marine food web, and they play a key role in removing carbon dioxide from the air. Read more
Global Warming
June 3, 2010Global warming is happening now, and scientists are confident that greenhouse gases are responsible. To understand what this means for humanity, it is necessary to understand what global warming is, how scientists know it's happening, and how they predict future climate. Read more
Sea Ice
April 20, 2009Polar sea ice grows and shrinks dramatically each year, driven by seasonal cycles. Habitat for wildlife and harbinger of changing climate, sea ice offers scientists important clues about the state of our planet. Read more
Climate and Earth’s Energy Budget
January 14, 2009Earth’s temperature depends on how much sunlight the land, oceans, and atmosphere absorb, and how much heat the planet radiates back to space. This fact sheet describes the net flow of energy through different parts of the Earth system, and explains how the planetary energy budget stays in balance. Read more
Tropical Deforestation
March 30, 2007Tropical forests are home to half the Earth's species, and their trees are an immense standing reservoir of carbon. Deforestation will have increasingly serious consequences for biodiversity, humans, and climate. Read more
Hurricanes: The Greatest Storms on Earth
November 1, 2006Few things in nature can compare to the destructive force of a hurricane. Called the greatest storm on Earth, a hurricane is capable of annihilating coastal areas with sustained winds of 155 mph or higher and intense areas of rainfall and a storm surge. In fact, during its life cycle a hurricane can expend as much energy as 10,000 nuclear bombs! Read more
Ask-A-Scientist
July 25, 2006Questions from visitors to the Earth Observatory and answers from scientists. Read more
Aura: A Mission Dedicated to the Health of Earth's Atmosphere
December 7, 2004On July 15, 2004 at 3:02 a.m., NASA launched the Aura satellite, the third flagship in a series of Earth-observing satellites designed to view Earth as a whole system, observe the net results of complex interactions within the climate system, and understand how the planet is changing in response to natural and human influences. Read more
GRACE Fact Sheet
March 30, 2004Launched in March 2002, the Gravity Recovery and Climate Experiment is a five-year mission intended to produce maps of the Earth’s gravity field with unprecedented precision and resolution. Read more
Watching our Ozone Weather
August 22, 2003Until about 30 years ago, atmospheric scientists believed that all of the ozone in the lower atmosphere (troposphere) intruded from the upper atmosphere (stratosphere), where it formed by the action of sunlight on oxygen molecules. Read more
Chemistry in the Sunlight
January 28, 2003Ozone has proven to be among the most difficult air pollutants to control. To control ozone requires understanding its complex chemistry and how the chemical travels from one locality to another. Chemistry in the Sunlight explains basic aspects of ozone formation and provides a sample set of chemical reactions involved in ozone production. Read more
Solar Radiation and Climate Experiment (SORCE) Fact Sheet
January 21, 2003Earth scientists will move a step closer to a full understanding of the Sun's energy output with the launch of the Solar Radiation and Climate Experiment (SORCE) satellite. SORCE will be equipped with four instruments now being built at the University of Colorado that will measure variations in solar radiation much more accurately than anything now in use and observe some of the spectral properties of solar radiation for the first time. With data from NASA's SORCE mission, researchers should be able to follow how the Sun affects our climate now and in the future. (Original 2001-11-30; updated 2003-01-21) Read more
ICESat Factsheet
January 9, 2003The ICESat mission will provide multi-year elevation data needed to determine ice sheet mass balance as well as cloud property information, especially for stratospheric clouds common over polar areas. It will also provide topography and vegetation data around the globe, in addition to the polar-specific coverage over the Greenland and Antarctic ice sheets. Read more
CALIPSO: A Global Perspective of Clouds and Aerosols from Space
July 26, 2002The Cloud-Aerosol Lidar and Infrared Pathfinder Satellite Observations (CALIPSO) satellite mission helps scientists answer significant questions about climatic processes by providing new information on clouds and aerosols. Read more
Human Spaceflight Factsheet
July 9, 2002Astronaut photography of Earth from the first space flights in the 1960s formed the foundation for the remote sensing technologies that followed. Read more
Aqua
June 24, 2002Aqua carries six state-of-the-art instruments to observe the Earth's oceans, atmosphere, land, ice and snow covers, and vegetation, providing high measurement accuracy, spatial detail, and temporal frequency. This comprehensive approach enables scientists to study interactions among the many elements of the Earth system. Read more
NOAA-M Continues Polar-Orbiting Satellite Series
June 21, 2002Since the 1960s, NASA has developed polar-orbiting operational environmental satellites for the National Oceanic and Atmospheric Administration (NOAA). NOAA-M, the latest NOAA spacecraft, was launched on June 24, 2002. Read more
The Ozone We Breathe
April 19, 2002Ozone in the lower atmosphere (troposphere) is toxic to human beings and many species of plants, causing harm without visible symptoms. The Ozone We Breathe focuses chiefly on the ozone's effects on human respiratory health and and the productivity of agricultural crops. Read more
Highways of a Global Traveler - Tracking Tropospheric Ozone
March 22, 2002Ozone in the lower atmosphere (troposphere) is toxic to human beings and to many other living things that breathe it. After combining satellite observations with data-rich models that simulate the atmosphere’s chemistry and dynamics, scientists are finding tropospheric ozone in some unexpected places. Tropospheric ozone turns out to be an intercontinental traveler, crossing geographic and political boundaries. Read more
Stratospheric Aerosol and Gas Experiment III
March 5, 2002The Stratospheric Aerosol and Gas Experiment (SAGE III) is a fourth-generation satellite instrument for observing the long-term health of the upper atmosphere, including the amounts of ozone, aerosols (suspended particles), and water vapor. Read more
Weather Forecasting Through the Ages
February 25, 2002Only fifty years ago, weather forecasting was an art, derived from the inspired interpretation of data from a loose array of land-based observing stations, balloons, and aircraft. Since then it has evolved substantially, based on an array of satellite and other observations and sophisticated computer models simulating the atmosphere and sometimes additional elements of the Earth's climate system. The AIRS/AMSU/HSB combination on board the [soon to be launched] EOS Aqua satellite should further these advances, enabling more accurate predictions over longer periods. Read more
Research Satellites for Atmospheric Science, 1978-Present
December 10, 2001NASA and its affiliated agencies and research institutions developed a series of research satellites that have enabled scientists to test new remote sensing technologies that have advanced scientific understanding of both chemical and physical changes in the atmosphere. Read more
Ultraviolet Radiation: How It Affects Life on Earth
September 6, 2001Stratospheric ozone depletion due to human activities has resulted in an increase of ultraviolet radiation on the Earth's surface. The article describes some effects on human health, aquatic ecosystems, agricultural plants and other living things, and explains how much ultraviolet radiation we are currently getting and how we measure it. Read more
Biomass Burning
March 19, 2001Biomass burning is the burning of living and dead vegetation, including both human-initiated burning for land clearing, and burning induced by lightning and other natural sources. Researchers with the Biomass Burning Project at NASA Langley Research Center are seeking to understand the impact that biomass burning has on the Earth's atmosphere and climate. Read more
Earth Observing 1 (EO-1)
November 15, 2000In 2000, NASA launched Earth Observing-1 (EO-1). While flying at an altitude of 705-kilometers, EO-1's primary focus is to test advanced instruments, spacecraft systems, and mission concepts in flight. EO-1 will also return scientific data which is used in comparison with other satellite data to ensure the continuity of land-imaging data. Read more
Measuring Vegetation (NDVI & EVI)
August 30, 2000In an effort to monitor major fluctuations in vegetation and understand how they affect the environment scientist use satellite remote sensors to measure and map the density of green vegetation over the Earth. By carefully measuring the wavelengths and intensity of visible and near-infrared light reflected by the land surface back up into space, scientists use an algorithm called a “Vegetation Index” to quantify the concentrations of green leaf vegetation around the globe. Read more
Drought: The Creeping Disaster
August 28, 2000Though it is a gradual disaster, drought can have devastating effects on agriculture and water supplies, but monitoring and forecasts can allow people to take early actions that prevent harsh impacts later. Read more
Watching the Sun
June 30, 2000The Active Cavity Radiometer Irradiance Monitor III will monitor the sun's total radiation output so scientists can better predict the sun's effect on global climate change. Read more
Space-based Observations of the Earth
May 11, 2000With increasingly sophisticated satellite remote sensors, we can measure a wide range of geophysical parameters (such as surface temperature, distribution of clouds and aerosol particles, the abundance of trace gases in the atmosphere, or the distribution and types of life on land and in the ocean) with unprecedented accuracy and resolution. Read more
Sunspots and the Solar Max
February 22, 2000This fact sheet describes solar phenomenon such as sunspots and the solar wind. Read more
ACRIMSAT
December 21, 1999By measuring the total amount of energy that the sun delivers to the Earth with ACRIMSAT, scientists will be able to build better scientific models of the Earth’s climate system, providing a vital piece of the global climate change puzzle. Read more
Global Fire Monitoring
October 22, 1999Forest fires, brush fires, and slash and burn agriculture—types of biomass burning—are a significant force for environmental change. Fires may play an important role in climate change, emitting both greenhouse gases and smoke particles into the atmosphere. Read more
Remote Sensing
September 17, 1999Remote sensing is the science and art of identifying, observing, and measuring an object without coming into direct contact with it. This involves the detection and measurement of radiation of different wavelengths reflected or emitted from distant objects or materials, by which they may be identified and categorized. Read more
Ozone
July 30, 1999A relatively unstable molecule that represents a tiny fraction of the atmosphere, ozone is crucial for life on Earth. Depending on where ozone resides, it can protect or harm life. Read more
QuikSCAT
July 23, 1999QuikSCAT provides climatologists, meteorologists and oceanographers with daily, detailed snapshots of the winds swirling above the world’s oceans. Read more
Land Cover Classification
July 16, 1999For years scientists across the world have been mapping changes in the landscape (forest to field, grassland to desert, ice to rock) to prevent future disasters, monitor natural resources, and collect information on the environment. While land cover can be observed on the ground or by airplane, the most efficient way to map it is from space. Read more
Landsat 7 Fact Sheet
June 24, 1999The latest mission in the Landsat series—Landsat 7—continues the flow of global change information to users worldwide. Scientists use Landsat satellites to gather remotely sensed images of the land surface and surrounding coastal regions for global change research, regional environmental change studies and other civil and commercial purposes. Read more
Tropical Rainfall Measuring Mission
May 21, 1999The Tropical Rainfall Measuring Mission (TRMM), is the first mission dedicated to measuring tropical and subtropical rainfall through microwave and visible infrared sensors, and includes the first spaceborne rain radar. Read more
Changing Global Cloudiness
May 13, 1999Clouds are one of the most obvious and influential features of Earth’s climate system. They are also one of its most variable components. The natural diversity and variability of clouds has intrigued and challenged researchers for centuries. Read more
Changing Global Land Surface
May 13, 1999Satellite remote sensing enables researchers to consistently monitor distribution and seasonal changes of the world’s vegetation and the exchanges of water and carbon between land vegetation and the atmosphere. These observations will help us understand the rate of change of atmospheric carbon dioxide and its effect on climate. Read more
What is El Nino? Fact Sheet
April 27, 1999During an El Niño, the relationships between winds and ocean currents in the Pacific Ocean change, with an impact on weather conditions around the world. Read more
La Niña Fact Sheet
April 27, 1999The phenomenon known as El Niño is sometimes reverses, leading to strong trade winds, colder than normal water off the coast of Peru, and warmer than normal water near Australia. This cold counterpart to El Niño is known as La Niña. Read more
Ocean and Climate Fact Sheet
April 27, 1999The Earth’s ocean and atmosphere are locked in an embrace. As one changes, so does the other. Read more
What is a Coccolithophore? Fact Sheet
April 26, 1999Coccolithophores are one-celled marine plants that surround themselves with a microscopic plating made of limestone (calcite). Read more
Polar Ice Fact Sheet
April 24, 1999Polar ice consists of sea ice, ice sheets, and glaciers. Extending over vast areas of the polar regions, this ice provides some early clues about climate change. Read more
Terra Spacecraft Fact Sheet
March 1, 1999On December 18, 1999, NASA launched a new flagship, the Terra satellite, to begin collecting a new 18-year global data set on which to base future scientific investigations about our complex home planet. Read more
Clouds & Radiation Fact Sheet
March 1, 1999The study of clouds, where they occur, and their characteristics, plays a key role in the understanding of climate change. Low, thick clouds reflect solar radiation and cool the Earth's surface. High, thin clouds transmit incoming solar radiation and also trap some of the outgoing infrared radiation emitted by the Earth, warming the surface. Read more
