Earth Observation Archives

August 20, 2009April 26, 2016 by Nancy Atkinson

NASA Video of Hurricane Bill

Hurricane Bill, August 19, 2009. Credit: MODIS/NASA/NOAA

This just in — the NASA/NOAA satellite GOES-14 has just released video taken on August 20 (that’s today!) of Hurricane Bill, the first hurricane of the season. This spectacular video is a collection of a few quick movies put together by the GOES-14 team and includes an impressive zoom-out, showing how big the hurricane is, relative to the hemisphere. Yes, Bill is large, with sustained winds of 217 kph (135 mph), making it a powerful Category 4 storm. The winds extend outward up to 80 miles from the center. Bill stretches more than 1,200 kilometers (746 miles) across, and the storm’s partially cloud-filled eye is nearly 50 kilometers (31 miles) wide.

See an image below of Bill from NASA’s MODIS satellite, taken on August 19, 2009.

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As of August 20 at 5 pm EDT, Hurricane Bill was located 790 miles SSE of Bermuda, while continuing to move quickly off to the northwest. Bill should begin turning in a more northerly direction by later Friday.

Based on all available forecast data at this time, it appears that Bill will track east of the Eastern U.S. Coast over the next few days.

You can follow a tracker on Weather.com to find out where Hurricane Bill is currently located.

August 17, 2009August 17, 2009 by Nancy Atkinson

Watch Satellite Data In Action

Ever wonder about all the different data that satellites are collecting as they orbit Earth? This video is a sample of Bella Gaia, a 45-minute movie is meant to be watched in an immersive theater, such as a fulldome planetarium. This clip is an audio visual “Living Atlas” journey of our world, showing the beauty and fragility of planet Earth as seen through satellite data. Created by director and violist Kenji Williams, the The movie is based on the stunning orbital imagery created by SCISS’ Uniview software and NASA, and shows data ranging from oil consumption and air traffic, over Earth’s magnetosphere and polar sub storms to time-lapse images of the Arctic ice melt. It’s a new way to look at Earth, and hopefully will instill some of the awe that the first “Earthrise” images brought. Look for the full version coming soon to an immersive theater near you. More info on Bella Gaia.

August 4, 2009January 24, 2021 by Nancy Atkinson

LCROSS Sees Life on Earth

LCROSS UV/Visible spectrum. Credit: NASA

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The LCROSS spacecraft took a look back at Earth, and guess what it saw? Evidence of intelligence? Not so much. But it did see evidence of life. On Aug. 1, 2009, the LCROSS spacecraft took a gander at Earth to help calibrate and test its science payload. During the Earth observations, the spacecraft’s spectrometers were able to detect the signatures of the Earth’s water, ozone, methane, oxygen, carbon dioxide and possibly vegetation.

Phil Plait explained on Bad Astronomy that this spectrum covers part of the ultraviolet and visible range of light, and this type of observation with better instruments in the future could help us find life on other planets. Phil wrote. “You can see that LCROSS clearly detected ozone (O3) and water, which you might see on any old planet. But it also saw a feature that is from free oxygen (O2), something you don’t see just anywhere .… The only reason we have a lot of it in our air (more than 20% of the Earth’s atmosphere is O2) is because we have life in the form of plants.” Check out Phil’s post here.

The spacecraft also took these images of Earth, again, helping to refine camera exposure settings, check instrument pointing alignment, and check radiometric and wavelength calibrations.

LCROSS is in an elongated Earth orbit, and on course to impact the Moon’s south pole in October. From its current vantage point of 223,700 miles (360,000 km) from Earth, the LCROSS science team changed exposure and integration settings on the spacecraft’s infrared cameras and spectrometers and performed a crossing pattern, pushing the smaller fields of view of the spectrometers across the Earth’s disk. At this range, the Earth was approximately 2.2 degrees in diameter.

“The Earth-look was very successful,” said Tony Colaprete, LCROSS project scientist. “The instruments are all healthy and the science teams was able to collect additional data that will help refine our calibrations of the instruments.”

An additional Earth-look and a moon-look are scheduled for the remainder of the cruise phase of the mission.

Sources: NASA, Bad Astronomy

July 27, 2009April 26, 2016 by Nancy Atkinson

Declassified Ice Loss Images

Ice loss in Barrow Alaska from 2006 to 2007. Credit: US Geological Survey

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Last week the US government released more than a thousand intelligence images of Arctic ice that have been used to help scientists study the impact of climate change. The images were taken by spy satellites, as part of the Medea program, which lets scientists request spy pictures from environmentally sensitive locations around the world. After they were taken, the Bush Administration released the photographs to the scientists but deemed them “unsuitable for public release.” Earlier this month, the National Academy of Sciences recommended the Obama Administration declassify the photos, which they did within a few hours of the recommendation.

Various blogs are saying these dramatic images are faked, but since they are available through the US Geological Survey , that hardly seems likely. Over 700 images show changes of sea ice in various recent years from six sites around the Arctic Ocean, with an additional 500 images of 22 sites in the United States.

Ice loss in the Beaufort Sea. Credit: USGS

Scientists request ice pictures to be taken by intelligence satellites because the resolution is much greater, in some cases, than other available satellite images. According to Reuters, the newly declassified Arctic images have a resolution of about 1 yard (1 meter), a vast improvement on previously available pictures of sea ice which have a resolution between 15 and 30 meters.

Ice loss at the Bering Glacier. Credit: USGS

Sources: Reuters, USGS, TrueSlant

July 24, 2009December 24, 2015 by Nancy Atkinson

The Grand Canyon From Space

Grand Canyon from space. Click for larger version. Credit: ESA

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The Grand Canyon is an awesome sight on Earth — one of the seven natural wonders of the world – and it looks breathtaking from space, too. This image was taken by the Envisat satellite, showing canyon walls, rock structures, old lava flows, buttes, ravines, stair-step topography in hues of pink, violet and gray.

Also visible in the image are the Colorado Plateau (upper right corner), the Mogollon Plateau (dark area under Colorado Plateau), Lake Meade (Y-shaped water body left of the canyon), Las Vegas, Nevada (bright white and blue area left of Lake Meade) and the southern tip of Utah (upper left).

Although a number of processes combined to create the Grand Canyon, it was formed primarily by the eroding action of the Colorado River that began about six million years ago. Other contributing factors include volcanism, continental drift and the semiarid climate.

As water erosion sculpted this majestic showplace, it revealed layers and layers of exposed rocks that provide us with a profound record of geologic events. As some of Earth’s oldest rock lies at the bottom of the canyon, it is said to be 1800 meters and a billion years deep. It is about 443 km long and 8 to 29 km wide.

This image was acquired by Envisat’s Medium Resolution Imaging Spectrometer (MERIS) instrument on 10 May 2009, working in Full Resolution mode to provide a spatial resolution of 300 meters.

Source: ESA

June 30, 2009December 24, 2015 by Nancy Atkinson

NASA, Japan Release Most Complete Topographic Map of Earth

In this perspective view, the new topographic maps show the LA Basin. Credit: NASA, MET

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Topographic maps are some of the most used and valuable maps for both government and the general public. Now, NASA and Japan have released a new digital topographic map of Earth Monday that covers more of our planet than ever before and was created from nearly 1.3 million individual stereo-pair images collected by the Japanese Advanced Spaceborne Thermal Emission and Reflection Radiometer, or ASTER, on board NASA’s Terra spacecraft. It is available online to users everywhere at no cost.

“This is the most complete, consistent global digital elevation data yet made available to the world,” said Woody Turner, ASTER program scientist at NASA Headquarters in Washington. “This unique global set of data will serve users and researchers from a wide array of disciplines that need elevation and terrain information.”
ASTER is one of five Earth-observing instruments launched on Terra in December 1999. ASTER acquires images from the visible to the thermal infrared wavelength region, with spatial resolutions ranging from about 50 to 300 feet.

According to Mike Abrams, ASTER science team leader at JPL the new topographic information will be of value throughout the Earth sciences and has many practical applications. “ASTER’s accurate topographic data will be used for engineering, energy exploration, conserving natural resources, environmental management, public works design, firefighting, recreation, geology and city planning, to name just a few areas,” Abrams said.

Click here for visualizations of the new ASTER topographic data.

Click here to download the ASTER global digital elevation model.

NASA and Japan’s Ministry of Economy, Trade and Industry, known as METI, developed the data set.

Global map from ASTER. Credit: NASA, METI

Previously, the most complete topographic set of data publicly available was from NASA’s Shuttle Radar Topography Mission. That mission mapped 80 percent of Earth’s landmass, between 60 degrees north latitude and 57 degrees south. The new ASTER data expands coverage to 99 percent, from 83 degrees north latitude and 83 degrees south. Each elevation measurement point in the new data is 98 feet apart.

The ASTER data fill in many of the voids in the shuttle mission’s data, such as in very steep terrains and in some deserts,” said Michael Kobrick, Shuttle Radar Topography Mission project scientist at the Jet Propulsion Laboratory. “NASA is working to combine the ASTER data with that of the Shuttle Radar Topography Mission and other sources to produce an even better global topographic map.”

Source: NASA

June 25, 2009December 24, 2015 by Nancy Atkinson

Volcanic Shockwave Captured by ISS Imagery

Sarychev Volcano as seen from the ISS. Credit: NASA

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These images of Sarychev Volcano were popping up everywhere in the internet yesterday, but unfortunately I was out of intertube contact most of the day. But these images are too awesome not to share! Astronauts on board the International Space Station took these striking views of Sarychev Volcano (Kuril Islands, northeast of Japan) on June 12, 2009. Notice the shock wave around the edge of the volcano’s plume and the “hole” the clouds that the eruption caused. Sarychev Peak is one of the most active volcanoes in the Kuril Island chain, and it is located on the northwestern end of Matua Island. Here are few more images taken in sequence as the ISS flew 354 km (220 miles) overhead:

Second image of Sarychev Volcano. Credit: NASA

Volcanologists say these images are exciting because they capture several phenomena that occur during the earliest stages of an explosive volcanic eruption. The main column is one of a series of plumes that rose above Matua Island on June 12. The plume appears to be a combination of brown ash and white steam. The vigorously rising plume gives the steam a bubble-like appearance. The eruption cleared a circle in the cloud deck. The clearing may result from the shockwave from the eruption or from sinking air around the eruption plume: as the plume rises, air flows down around the sides like water flowing off the back of a surfacing dolphin. As air sinks, it tends to warm and expand; clouds in the air evaporate.

Also visible is material from the eruption falling down the slopes of the volcano.

Third image of the volcano. Credit: NASA

These images were taken by the Expedition 20 crew on the ISS, using a Nikon D2XS digital camera fitted with a 400 mm lens, and is provided by the ISS Crew Earth Observations experiment and Image Science & Analysis Laboratory, Johnson Space Center.

Source: NASA Earth Observatory

June 2, 2009April 15, 2019 by Nancy Atkinson

Scientists Follow the Poop to Find Penguins From Space

An emporer penguin colony at Halley Bay. Credit: British Antarctic Survey

This just in from the ‘things kids can giggle about’ department: British scientists are using satellite images to find colonies of emperor penguins in Antarctica. While their natural camouflage makes them blend into the shadows of the sea ice where they breed, their droppings, or guano, show up perfectly from space. “We can’t see actual penguins on the satellite maps because the resolution isn’t good enough,” said mapping expert Peter Fretwell. “But during the breeding season the birds stay at a colony for eight months. The ice gets pretty dirty and it’s the guano stains that we can see.”

Stains on the ice visible on this satellite image. Credit: British Antarctic Survey

Emperor penguins spend a large part of their lives at sea. During the Antarctic winter when temperatures drop to -50°C they return to their colonies to breed on sea-ice, but this is a time when it is most difficult for scientists to monitor them. Knowing their location provides a baseline for monitoring their response to environmental change.

Reddish brown patches of guano on the ice, visible in satellite images, provide a reliable indication of their location.

British Antarctic Survey Penguin ecologist Dr Phil Trathan says: “This is a very exciting development. Now we know exactly where the penguins are, the next step will be to count each colony so we can get a much better picture of population size. Using satellite images combined with counts of penguin numbers puts us in a much better position to monitor future population changes over time.”

Emporer penguin. — Emperor penguin. Photo credit: Samuel Blanc

The method helped scientists identify 38 penguin colonies — of those, 10 were new. Of previously known colonies, six had re-located and six were not found. Estimates put the total number of penguins at between 200,000 and 400,000 breeding pairs.

Source: British Antarctic Survey

May 28, 2009December 24, 2015 by Nancy Atkinson

Researchers Seeing Red on Ocean Health

The MODIS instrument on NASA’s Aqua satellite compiled this global view of the amount of fluorescent light emitted by phytoplankton in the ocean. Credit: Oregon State University

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With the help of an orbiting satellite, researchers have conducted the first global analysis of the health and productivity of ocean plants. Using the Moderate Resolution Imaging Spectroradiometer (MODIS) on NASA’s Aqua satellite, scientists have for the first time measured remotely the amount of fluorescent red light emitted by ocean phytoplankton and assess how efficiently the microscopic plants are turning sunlight and nutrients into food through photosynthesis. Now that they have their first data, this method should allow scientists to effectively keep an eye on the health of our oceans. So what did they find out so far?

Over the past two decades, scientists have employed various satellite sensors to measure the amount and distribution of the green pigment chlorophyll, an indicator of the amount of plant life in the ocean. But with MODIS, “red-light fluorescence” has been observed over the open ocean.

“Chlorophyll gives us a picture of how much phytoplankton is present,” said Scott Doney, a marine chemist from the Woods Hole Oceanographic Institution and a co-author of the paper. “Fluorescence provides insight into how well they are functioning in the ecosystem.”

Phytoplankton -- such as this colony of chaetoceros socialis -- naturally give off fluorescent light as they dissipate excess solar energy that they cannot consume through photosynthesis. Credit: Maria Vernet, Scripps Institution of Oceanography

Red-light fluorescence reveals insights about the physiology of marine plants and the efficiency of photosynthesis, as different parts of the plant’s energy-harnessing machinery are activated based on the amount of light and nutrients available. For instance, the amount of fluorescence increases when phytoplankton are under stress from a lack of iron, a critical nutrient in seawater. When the water is iron-poor, phytoplankton emit more solar energy as fluorescence than when iron is sufficient.

The fluorescence data from MODIS gives scientists a tool that enables research to reveal where waters are iron-enriched or iron-limited, and to observe how changes in iron influence plankton. The iron needed for plant growth reaches the sea surface on winds blowing dust from deserts and other arid areas, and from upwelling currents near river plumes and islands.

The new analysis of MODIS data has allowed the research team to detect new regions of the ocean affected by iron deposition and depletion. The Indian Ocean was a particular surprise, as large portions of the ocean were seen to “light up” seasonally with changes in monsoon winds. In the summer, fall, and winter – particularly summer – significant southwesterly winds stir up ocean currents and bring more nutrients up from the depths for the phytoplankton. At the same time, the amount of iron-rich dust delivered by winds is reduced.

This data-based map shows iron dust deposition on the oceans in spring 2004. Areas with low dust deposition have high fluorescence yields. Credit: NASA's Scientific Visualization Studio

“On time-scales of weeks to months, we can use this data to track plankton responses to iron inputs from dust storms and the transport of iron-rich water from islands and continents,” said Doney. “Over years to decades, we can also detect long-term trends in climate change and other human perturbations to the ocean.”

Climate change could mean stronger winds pick up more dust and blow it to sea, or less intense winds leaving waters dust-free. Some regions will become drier and others wetter, changing the regions where dusty soils accumulate and get swept up into the air. Phytoplankton will reflect and react to these global changes.

Single-celled phytoplankton fuel nearly all ocean ecosystems, serving as the most basic food source for marine animals from zooplankton to fish to shellfish. In fact, phytoplankton account for half of all photosynthetic activity on Earth. The health of these marine plants affects commercial fisheries, the amount of carbon dioxide the ocean can absorb, and how the ocean responds to climate change.

“This is the first direct measurement of the health of the phytoplankton in the ocean,” said Michael Behrenfeld, a biologist who specializes in marine plants at the Oregon State University in Corvallis, Ore. “We have an important new tool for observing changes in phytoplankton every week, all over the planet.”

Source: NASA

May 18, 2009December 24, 2015 by Nancy Atkinson

First Observations of Biological Particles in High-Altitude Clouds

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A team of atmospheric chemists has moved closer to what’s considered the “holy grail” of climate change science: the first-ever direct detections of biological particles within ice clouds. Ice in Clouds Experiment – Layer Clouds (ICE-L) team mounted a mass spectrometer onto a C-130 aircraft and made a series of high-speed flights through a type of cloud known as a wave cloud. Analysis of the ice crystals revealed that the particles that started their growth were made up almost entirely of either dust or biological material such as bacteria, fungal spores and plant material. While it has long been known that microorganisms become airborne and travel great distances, this study is the first to yield direct data on how they work to influence cloud formation.

The team, led by Kimberly Prather and Kerri Pratt of the University of California at San Diego, Scripps Institution of Oceanography, performed in-situ measurements of cloud ice crystal residues and found that half were mineral dust and about a third were made up of inorganic ions mixed with nitrogen, phosphorus and carbon–the signature elements of biological matter.

The second-by-second speed of the analysis allowed the researchers to make distinctions between water droplets and ice particles. Ice nuclei are rarer than droplet nuclei.

The team demonstrated that both dust and biological material indeed form the nuclei of these ice particles, something that previously could only be simulated in laboratory experiments.

“This has really been kind of a holy grail measurement for us,” said Prather.

“Understanding which particles form ice nuclei, and which have extremely low concentrations and are inherently difficult to measure, means you can begin to understand processes that result in precipitation. Any new piece of information you can get is critical.”

The findings suggest that the biological particles that get swept up in dust storms help to induce the formation of cloud ice, and that their region of origin makes a difference. Evidence is increasingly suggesting that dust transported from Asia could be influencing precipitation in North America, for example.

Researchers hope to use the ICE-L data to design future studies timed to events when such particles may play a bigger role in triggering rain or snowfall.

“If we understand the sources of the particles that nucleate clouds, and their relative abundance, we can determine their impact on climate,” said Pratt, lead author of the paper.

The effects of tiny airborne particles called aerosols on cloud formation have been some of the most difficult aspects of weather and climate for scientists to understand.

In climate change science, which derives many of its projections from computer simulations of climate phenomena, the interactions between aerosols and clouds represent what scientists consider the greatest uncertainty in modeling predictions for the future.

“By sampling clouds in real time from an aircraft, these investigators were able to get information about ice particles in clouds at an unprecedented level of detail,” said Anne-Marie Schmoltner of NSF’s Division of Atmospheric Sciences, which funded the research.

Source: EurekAlert