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NASA: Volcán de Fuego

A Deadly Eruption Rocks Guatemala

A Deadly Eruption Rocks Guatemala

Fuego in Guatemala is one of Central America’s most active volcanoes. For years, the towering Volcán de Fuego has puffed continuously, punctuated by occasional episodes of explosive activity, big ash plumes, lava flows, and avalanche-like debris slides known as pyroclastic flows.

Just before noon on June 3, 2018, the volcano produced an explosive eruption that sent ash billowing thousands of meters into the air. A deadly mixture of ash, rock fragments, and hot gases rushed down ravines and stream channels on the sides of the volcano. Since these pyroclastic flows often move at speeds of greater than 80 kilometers (50 miles) per hour, they easily topple trees, homes, or anything else in their path. According to news reports, more than two dozen people were killed. As a precautionary measure, thousands of other people have been evacuated.

The Visible Infrared Imaging Radiometer Suite (VIIRS) on Suomi NPP acquired this image of the ash plume at 1 p.m. local time (19:00 Universal Time) on June 3, 2018, after the ash (brown) had punched through a deck of clouds. A report from the Washington Volcanic Ash Advisory Center estimated the plume’s maximum height at 15 kilometers (9 miles). Imagery from a geostationary satellite showed winds blowing the plume to the east. The eruption deposited ash on several communities surrounding the volcano, including Guatemala City, which is 70 kilometers (40 miles) to the east.

In addition to ash, the plume contains gaseous components invisible to the human eye, including sulfur dioxide (SO2). The gas can affect human health—irritating the nose and throat when breathed in—and reacts with water vapor to produce acid rain. Sulfur dioxide also can react in the atmosphere to form aerosol particles, which can contribute to outbreaks of haze and sometimes cool the climate.

Satellite sensors such as the Atmospheric Infrared Sounder (AIRS) on the Aqua satellite and the Ozone Mapping Profiler Suite (OMPS) on Suomi NPP make frequent observations of sulfur dioxide. The map above shows concentrations of sulfur dioxide in the middle troposphere at an altitude of 8 kilometers (5 miles) as detected by OMPS on June 3.

Upon seeing data collected by AIRS several hours after the eruption that showed high levels of sulfur dioxide in the upper troposphere, Michigan Tech volcanologist Simon Carn tweeted that this appeared to be the “highest sulfur dioxide loading measured in a Fuego eruption in the satellite era.”

NASA Earth Observatory images by Joshua Stevens, using VIIRS data from the Suomi National Polar-orbiting Partnership and OMPS data from the Goddard Earth Sciences Data and Information Services Center (GES DISC). Story by Adam Voiland.

Instrument(s):
Suomi NPP – VIIRS
Suomi NPP – OMPS

NASA captures deadly eruption in Guatemala

A Deadly Eruption Rocks Guatemala

acquired June 3, 2018
A Deadly Eruption Rocks Guatemala

acquired June 3, 2018 download large image (2 MB, PNG, 2779×1652)

Fuego in Guatemala is one of Central America’s most active volcanoes. For years, the towering Volcán de Fuego has puffed continuously, punctuated by occasional episodes of explosive activity, big ash plumes, lava flows, and avalanche-like debris slides known as pyroclastic flows.

Just before noon on June 3, 2018, the volcano produced an explosive eruption that sent ash billowing thousands of meters into the air. A deadly mixture of ash, rock fragments, and hot gases rushed down ravines and stream channels on the sides of the volcano. Since these pyroclastic flows often move at speeds of greater than 80 kilometers (50 miles) per hour, they easily topple trees, homes, or anything else in their path. According to news reports, more than two dozen people were killed. As a precautionary measure, thousands of other people have been evacuated.

The Visible Infrared Imaging Radiometer Suite (VIIRS) on Suomi NPP acquired this image of the ash plume at 1 p.m. local time (19:00 Universal Time) on June 3, 2018, after the ash (brown) had punched through a deck of clouds. A report from the Washington Volcanic Ash Advisory Center estimated the plume’s maximum height at 15 kilometers (9 miles). Imagery from a geostationary satellite showed winds blowing the plume to the east. The eruption deposited ash on several communities surrounding the volcano, including Guatemala City, which is 70 kilometers (40 miles) to the east.

In addition to ash, the plume contains gaseous components invisible to the human eye, including sulfur dioxide (SO2). The gas can affect human health—irritating the nose and throat when breathed in—and reacts with water vapor to produce acid rain. Sulfur dioxide also can react in the atmosphere to form aerosol particles, which can contribute to outbreaks of haze and sometimes cool the climate.

Satellite sensors such as the Atmospheric Infrared Sounder (AIRS) on the Aqua satellite and the Ozone Mapping Profiler Suite (OMPS) on Suomi NPP make frequent observations of sulfur dioxide. The map above shows concentrations of sulfur dioxide in the middle troposphere at an altitude of 8 kilometers (5 miles) as detected by OMPS on June 3.

Upon seeing data collected by AIRS several hours after the eruption that showed high levels of sulfur dioxide in the upper troposphere, Michigan Tech volcanologist Simon Carn tweeted that this appeared to be the “highest sulfur dioxide loading measured in a Fuego eruption in the satellite era.”

NASA Earth Observatory images by Joshua Stevens, using VIIRS data from the Suomi National Polar-orbiting Partnership and OMPS data from the Goddard Earth Sciences Data and Information Services Center (GES DISC). Story by Adam Voiland.

Instrument(s):
Suomi NPP – VIIRS
Suomi NPP – OMPS

NASA: California’s December Inferno

California’s December Inferno

It is rare for large wildfires to burn in California in December, which is usually a wet month for the state. In most years, a few hundreds acres might burn. The 2006 Shekell fire in Ventura charred 13,600 acres, making it the largest December fire in the state between 2000 and 2016.

In 2017, the Thomas fire shattered the record for December and may soon eclipse the worst blaze in any month. After burning for 16 days, the massive fire had scorched 272,000 acres (110,000 hectares or 425 square miles) and was just 60 percent contained. That made it the second largest fire on record in California, trailing only the Cedar fire, which burned 273,246 acres in 2003.

The Operational Land Imager (OLI) on Landsat 8 captured an image of the Thomas fire scar on December 18, 2017. The natural-color Landsat 8 image was draped over an ASTER-derived Global Digital Elevation Model, which shows the topography of the area. The fire raged first near Ventura, then burned the hills around communities of Ojai and Oak View. Firefighters put up a fierce fight and managed to prevent flames from descending into the valley towns. Flames then pushed west toward Summerland, Montecito, and Santa Barbara. As of December 20, the fire was still spreading along the northern edge of the burn scar.

Authorities reported that more than 1,200 structures—most of them in Ventura County—have been destroyed. Several factors came together to make the blaze difficult to control. An usually wet winter and spring in early 2017 caused vegetation to flourish. Then the dry season turned out to be excessively dry, and rains also have been scarce in the typically wetter months of November and December. All of that vegetation dried out and was primed to burn. Once the fire started, warm temperatures and unusually fierce Santa Ana winds caused the fire to spread rapidly.

After nearly two weeks of red flag conditions, a break in the weather has allowed firefighters to beat back the flames in the past few days. But fire officials still do not expect the Thomas fire to be completely contained until January 2018.

NASA Earth Observatory image by Joshua Stevens, using Landsat data from the U.S. Geological Survey and ASTER GDEM data from NASA/GSFC/METI/ERSDAC/JAROS, and U.S./Japan ASTER Science Team. Story by Adam Voiland.

Instrument(s):
Terra – ASTER
Landsat 8 – OLI

NASA: A Chilly End to 2017 for the Northeast

A Chilly End to 2017 for the Northeast

As 2017 drew toward a close, Arctic air spilled into the eastern United States and Canada for several days. Blasts of bitterly cold air set up a white Christmas for many Americans, and forecasters are expecting New Year’s Eve celebrations to be the coldest in recent memory for many areas.

The Moderate Resolution Imaging Spectroradiometer (MODIS) on NASA’s Terra satellite captured this image of the frozen Northeast landscape on December 28, 2017. Brisk northwesterly winds created rows of “cloud streets” as cold air blew over Lake Ontario and the Atlantic Ocean. A layer of snow covered much of New England and upstate New York.

Cloud streets are long parallel bands of cumulus clouds that form when cold air blows over warmer waters and a warmer air layer (temperature inversion) rests over the top of both. The comparatively warm water gives up heat and moisture to the cold air above, and columns of heated air called thermals naturally rise through the atmosphere. The temperature inversion acts like a lid. When the rising thermals hit it, they roll over and loop back on themselves, creating parallel cylinders of rotating air. As this happens, the moisture cools and condenses into flat-bottomed, fluffy-topped cumulus clouds that line up parallel to the direction of the prevailing winds.

While the cold streak has not broken all-time records, it is breaking records for individual days. On the day the image was acquired, weather observers on Mount Washington (New Hampshire) recorded a daily record low of -34 degrees Fahrenheit (-36° Celsius). Baltimore, Boston, Flint, New York, Montreal, and Toronto Cities have seen records fall during this cold snap.

When the ball drops in New York City on New Year’s Eve, forecasters expect air temperatures of 10°F (-12°C), with wind chills of -5°F ( -15°C). The last time it was so cold was in 1962; the record for the coldest ball drop occurred in 1917, when the air temperature was just 1°F (-17°C), according to Jason Samenow of the Capital Weather Gang.

The cold weather pattern has its origins in a large bulge, or ridge, in the jet stream that has brought unseasonably warm weather to Alaska. On the east side of this ridge, a trough in the jet stream plunged southward, bringing plenty of Arctic air with it. This orientation of the jet stream, which looks similar to the greek letter omega, is known as an omega block.

NASA image by Jeff Schmaltz, LANCE/EOSDIS Rapid Response. Story by Adam Voiland.

Instrument(s):
Terra – MODIS

9/28/17: Puerto Rico Landscape Ravaged by Hurricane Maria

Puerto Rico Landscape Ravaged by Hurricane Maria

acquired September 26, 2017 download large image (1 MB, JPEG, 2490×2713)
Puerto Rico Landscape Ravaged by Hurricane Maria

acquired September 23, 2016 download large image (1 MB, JPEG, 2490×2713)
acquired September 23, 2016 download large image (406 KB, JPEG, 720×480)
acquired September 26, 2017 download large image (342 KB, JPEG, 720×480)

Hurricane Maria tore across Puerto Rico on September 20, 2017, ravaging both urban and rural areas with category 4 winds and intense rainfall for several days. Most of the electric power grid and telecommunications network was knocked offline; towns both inland and at the coast were swamped with floodwaters and storm surges; and the lush green landscape turned brown from damaged vegetation and mud and debris deposits.

On September 26, 2017, the Operational Land Imager (OLI) on the Landsat 8 satellite captured some of the first natural-color satellite images of Puerto Rico after Hurricane Maria. Cloud cover is common in the tropics and has been particularly bad in the days since the storm, so researchers have been unable to see much from orbit.

The images above show the Rio Grande de Loíza, the island’s largest river by volume, where it meets the Atlantic Ocean several miles east of San Juan and west of Suárez. The images below show an interior portion of the island around the Lago Loíza reservoir, south of San Juan and north of Caguas. In each pair the second image shows the same area one year ago (September 23, 2016) so as to provide a proper seasonal comparison. (Note: the green color of the lake in 2016 could be an algae bloom or some other form of water vegetation.)

NASA’s Disasters Program has delivered to the Federal Emergency Management Agency (FEMA) a map of areas in eastern Puerto Rico that have likely been damaged as the result of the landfall of Hurricane Maria. The “damage proxy map” was created by the Advanced Rapid Imaging and Analysis team (Jet Propulsion Laboratory) and derived from synthetic aperture radar images from the European Space Agency’s Copernicus Sentinel-1A and Sentinel-1B satellites.

The National Oceanic and Atmospheric Administration is making aerial surveys of the U.S. states and territories affected by hurricanes Harvey, Irma, and Maria. Click here to see photos as they become available.

NASA Earth Observatory image by Joshua Stevens, using Landsat data from the U.S. Geological Survey. Story by Mike Carlowicz.

Instrument(s):
Landsat 8 – OLI
Landsat 8 – TIRS

3 Hurricanes: NASA

Credit:  NASA


NASA: Irma on 9/5/17

Hurricane Irma Strengthens

 


NASA: Hermine from Outer Space

Hurricane Hermine Approaches Florida

NY Times


NASA: The Alberta wildfire smoke becomes entrained within the clouds causing it to twist within the circular motion of the clouds and wind.

Smoke is drawn in to and transported along with the clouds over Canada.

NASA’s Aqua satellite captured this image of the clouds over Canada.  Entwined within the clouds is the smoke billowing up from the wildfires that are currently burning across a large expanse of the country.  The smoke has become entrained within the clouds causing it to twist within the circular motion of the clouds and wind.  This image was taken by the Moderate Resolution Imaging Spectroradiometer (MODIS) instrument on the Aqua satellite on May 9, 2016.

Image Credit: NASA image courtesy Jeff Schmaltz LANCE/EOSDIS MODIS Rapid Response Team, GSFC
Caption: Lynn Jenner

Last Updated: May 10, 2016
Editor: Lynn Jenner

In September and October 2015, tens of thousands of fires sent clouds of toxic gas and particulate matter into the air over Indonesia.

Fires Put a Carbon Monoxide Cloud over Indonesia

In September and October 2015, tens of thousands of fires sent clouds of toxic gas and particulate matter into the air over Indonesia. Despite the moist climate of tropical Asia, fire is not unusual during those months. For the past few decades, people have used fire to clear land for farming and to burn away leftover crop debris. What was unusual in 2015 was how many fires burned and how many escaped their handlers and went uncontrolled for weeks and even months.

To study the fires, scientists in Indonesia and around the world have been using many different tools—from sensors on the ground to data collected by satellites. The goal is to better understand why the fires became so severe, how they are affecting human health and the atmosphere, and what can be done to prepare for similar surges in fire activity in the future.

While some NASA satellite instruments captured natural-color images of the smoky pall, others focused on gases that are invisible to human eyes. For instance, the Measurement of Pollution in the Troposphere (MOPITT) sensor on Terra can detect carbon monoxide, an odorless, colorless, and poisonous gas. As shown by the map above, the concentration of carbon monoxide near the surface was remarkably high in September 2015 over Sumatra and Kalimantan.

“The 2015 Indonesian fires produced some of the highest concentrations of carbon monoxide that we have ever seen with MOPITT,” said Helen Worden, a scientist at the National Center for Atmospheric Research. Average carbon monoxide concentrations over Indonesia are usually about 100 parts per billion. In some parts of Borneo in 2015, MOPITT measured carbon monoxide concentrations at the surface up to nearly 1,300 parts per billion.

While all types of wildfires emit carbon monoxide as part of he combustion process, the fires in Indonesia released large amounts of the gas because in many cases the fuel burning was peat, a soil-like mixture of partly decayed plant material that builds up in wetlands, swamps, and partly submerged landscapes.

Read more about studies of Indonesia’s fire season in our new feature: Seeing Through the Smoky Pall.

NASA Earth Observatory map by Joshua Stevens and Jesse Allen, using data from the MOPITT Teams at the National Center for Atmospheric Research and the University of Toronto. Caption by Adam Voiland.

Instrument(s): 
Terra – MOPITT

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