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Earth Matters

On February 27, 2014, a Japanese rocket launched NASA’s latest satellite to advance how scientists study raindrops from space. The satellite, the Global Precipitation Measurement (GPM) Core Observatory, paints a picture of global precipitation every 30 minutes, with help from its other international satellite partners. It has provided innumerable insights into Earth’s precipitation patterns, severe storms, and into the rain and snow particles within clouds. It has also helped farmers trying to increase crop yields, and aided researchers predicting the spread of fires.

In honor of GPM’s fifth anniversary, we’re highlighting some of our favorite and most unique Earth Observatory stories, as made possible by measurements taken by GPM.

Credit: NASA

The Second Wettest October in Texas Ever

In Fall 2018, storm after storm rolled through and dumped record rainfall in parts of Texas. When Hurricane Willa hit Texas around October 24, the ground was already soaked. One particularly potent cold front in mid-October dropped more than a foot of rain in areas. By the end of the month, October 2018 was the second wettest month in Texas on record.

Read the full story, “Rainy October Soaks Texas

GPM measured the total amount of rainfall over the region from October 1 to October 31, 2018. The brightest areas reflect the highest rainfall amounts, with many places receiving 25 to 45 centimeters (10 to 17 inches) or more during this period. The satellite imagery can also be seen from natural-color satellite imagery.

Observing Rivers in the Air

With the GPM mission’s global vantage point, we can more clearly see how weather systems form and connect with one another. In this visualization from October 11-22, 2017, note the long, narrow bands of moisture in the air, known as “atmospheric rivers.” These streams are fairly common in the Pacific Northwest and frequently bring much of the region’s heavy rains and snow in the fall and winter. But this atmospheric river was unusual for its length—extending roughly 8,000 kilometers (5,000 miles) from Japan to Washington. That’s about two to three times the typical length of an atmospheric river.

Read the full story, “A River of Rain Connecting Asia and North America

Since atmospheric rivers often bring strong winds, they can force moisture up and over mountain ranges and drop a lot of precipitation in the process. In this case, more than four inches of rain fell on the western slopes of the Olympic Mountains and the Cascade Range, while areas to the east of the mountains (in the rain shadow) generally saw less than one inch.

Increasing Crop Yield for Farmers in Pakistan

Knowing how much precipitation is falling or has fallen is useful for people around the world. Farmers, in particular, are interested in knowing precipitation amounts so they can prevent overwatering or underwatering their crops.

The Sustainability, Satellites, Water, and Environment (SASWE) research group at the University of Washington has been working with the Pakistan Council of Research in Water Resources (PCRWR) to bring this kind of valuable information directly to the cell phones of farmers. A survey by the PCRWR found that farmers who used the text message alerts reported a 40 percent savings in water. Anecdotally, many farmers say their income has doubled because they got more crops by applying the correct amount of water.

Read the full story, “Smart Phones Bring Smart Irrigation

The map above shows the forecast for evapotranspiration for October 16-22, 2018. Evapotranspiration is an indication of the amount of water vapor being removed by sunlight and wind from the soil and from plant leaves. It is calculated from data on temperature, humidity, wind speed, and solar radiation, as well as a global numerical weather model that assimilates NASA satellite data. The team also looks at maps of precipitation, temperature and wind speed to help determine crop conditions. Precipitation data comes from GPM that is combined with ground-based measurements from the Pakistan Meteorological Department.

Forecasting Fire

Precipitation can drastically affect the spread of a fire. For instance, if a region has not received normal precipitation for weeks or months, the vegetation might be drier and more prone to catching fire. 

NASA researchers recently created a model that analyzes various weather factors that lead to the formation and spread of fires. The Global Fire Weather Database (GFWED) accounts for local winds, temperatures, and humidity, while also being the first fire prediction model to include satellite–based precipitation measurements.

Read the full story, “Forecasting Fire

The animation above shows GFWED’s calculated fire danger around the world from 2015 to 2017. The model compiles and analyzes various data sets and produces a rating that indicates how likely and intense fire might become in a particular area. It is the same type of rating that many firefighting agencies use in their day–to–day operations. Historical data are available to understand the weather conditions under which fires have occurred in the past, and near–real–time data are available to gauge current fire danger.

Automatically Detecting Landslides

In this mountainous country of Nepal, 60 to 80 percent of the annual precipitation falls during the monsoon (roughly June to August). That’s also when roughly 90 percent of Nepal’s landslide fatalities occur. NASA researchers have designed an automated system to identify potential landslides that might otherwise go undetected and unreported. This information could significantly improve landslide inventories, leading to better risk management.

The computer program works by scanning satellite imagery for signs that a landslide may have occurred recently, looking at topographical features such as hill slopes.

Read the full story, “Automating the Detection of Landslides

The left and middle images above were acquired by the Landsat 8 satellite on September 15, 2013, and September 18, 2014—before and after the Jure landslide in Nepal on August 2, 2014. The image on the right shows that 2014 Landsat image processed with computer program. The red areas show most of the traits of a landslide, while yellow areas exhibit a few of the proxy traits.

The program also uses data from GPM to help pin when each landslide occurred. The GPM core satellite measures rain and snow several times daily, allowing researchers to create maps of rain accumulation over 24-, 48-, and 72-hour periods for given areas of interest—a product they call Detecting Real-time Increased Precipitation, or DRIP. When a certain amount of rain has fallen in a region, an email can be sent to emergency responders and other interested parties.

The GPM Core Observatory is a joint satellite project by NASA and the Japan Aerospace Exploration Agency. The satellite is part of the larger GPM mission, which consists of about a dozen international satellite partners to provide global observations of rain and snow.

To learn more about GPM’s accomplishments over the past five years, visit:

To learn more about the GPM mission, visit:

Beyond the Galapagos with Darwin

February 12th, 2019 by Adam Voiland

On February 12, 1809, Charles Robert Darwin was born in England in the town of Shrewsbury. The famed naturalist, geologist, and biologist is best known for his 19th century expedition to the Galápagos Islands, which inspired revolutionary insights about evolution and natural selection. Lesser known is that the expedition to the Galápagos was just one part of a much longer journey. The Second Voyage of the HMS Beagle brought Darwin and his fellow travelers to South America, Australia, Africa, and several islands in between. Here are a few interesting places where the HMS Beagle stopped that we have covered in earlier stories.

January 1832: The Dusty Canary Islands, Tenerife

Read more about this Landsat 8 image.

The crew of the Beagle was denied landing on Tenerife because of fears they might be carrying cholera. The Operational Land Imager (OLI) on Landsat 8 acquired this image of the island on January 25, 2016.

Darwin was struck by the intensity of the dust in this area. “The atmosphere is generally very hazy, chiefly due to an impalpable dust, which is constantly falling, even on vessels far out at sea,” he wrote. “It is produced, as I believe, from the wear and tear of volcanic rocks, and must come from the coast of Africa.”

Read more about this Terra image.

Christmas 1832: Cape Horn, South America

Read more about this Landsat 8 image.

Southwest of Cape Horn at the southern tip of South America, the ocean floor rises sharply. Along with the potent westerly winds that swirl around the Furious Fifties, this pushes up massive waves with frightening regularity. Add in frigid water temperatures, rocky coastal shoals, and stray icebergs—which drift north from Antarctica across the Drake Passage—and it is easy to see why the area is known as a graveyard for ships. In his journal, Darwin described the harrowing journey as the explorers tried to round the Horn just before Christmas.

“Great black clouds were rolling across the heavens, and squalls of rain, with hail, swept by us with such extreme violence, that the Captain determined to run into Wigwam Cove. This is a snug little harbor, not far from Cape Horn; and here, at Christmas-eve, we anchored in smooth water. The only thing which reminded us of the gale outside, was every now and then a puff from the mountains, which made the ship surge at her anchors.”

Charles Darwin
Read more about this astronaut photograph.

September 1835: The Galapagos

The Galapagos archipelago includes more than 125 islands, islets, and rocks populated by a diversity of wildlife. Charles Darwin’s book, The Voyage of the Beagle, cast a spotlight on the Galapagos, which he called “a little world within itself, or rather a satellite attached to America, whence it has derived a few stray colonists.” It was this little world that would revolutionize scientific understanding of biology and lead to Darwin’s On the Origin of Species, which would come to be known as the foundation of evolution.

Read more about this Aqua image.

November 1835: The Coral Reefs of Tahiti

On this stopover, Darwin had a chance to explore coral reef.

“We paddled for some time about the reef admiring the pretty branching Corals,” he wrote. “It is my opinion, that besides the avowed ignorance concerning the tiny architects of each individual species, little is yet known, in spite of the much which has been written, of the structure and origin of the Coral Islands and reefs.”

The Enhanced Thematic Mapper Plus on the Landsat 7 satellite captured this natural-color image of Tahiti on July 11, 2001. This island is part of a volcanic chain formed by the northwestward movement of the Pacific Plate over a fixed hotspot.

Read more about this Landsat 7 image.

1836: Pondering Phytoplankton Near Australia

All the sea travel offered plenty of time to observe and ponder the intricacies of phytoplankton.

“My attention was called to a reddish-brown appearance in the sea. The whole surface of the water, as it appeared under a weak lens, seemed as if covered by chopped bits of hay, with their ends jagged,” he wrote. “These are minute cylindrical, in bundles or rafts of from twenty to sixty in each…Their numbers must be infinite: the ship passed through several bands of them, one of which was about ten yards wide, and, judging from the mud-like color of the water, at least two and a half miles.”

On August 9, 2011, the Moderate Resolution Imaging Spectroradiometer (MODIS) on the Aqua satellite captured this image of a similar band of brown between the Great Barrier Reef and the Queensland shore. Though it’s impossible to identify the species from satellite imagery, such red-brown streamers are usually trichodesmium. Sailors have long called these brown streamers “sea sawdust.”

Read more about this Aqua image.

A Thanksgiving Journey

November 22nd, 2018 by Adam Voiland & Michael Carlowicz

Editor’s Note: We have highlighted the story of the Pilgrims and Thanksgiving several times over the years. Here are some of those pieces in one convenient place.

First stop, Holland. Image credit: NASA Earth Observatory image by Joshua Stevens, using Landsat data from the U.S. Geological Survey.

Most school children in America learn about the Pilgrims—the group of English settlers who endured a harrowing journey to the New World in 1620 on the Mayflower. It is sometimes overlooked, however, that Plymouth was not the first stop—nor the intended destination—for this congregation of religious separatists from the town of Scrooby in the English county of Nottinghamshire.

Before ever setting foot in North America, the Pilgrims spent several years living in Leiden, a city in the Netherlands. Most of the hundred or so people in the congregation lived in one-room cottages near Leiden University, in the shadow of the Pieterskerk, the oldest church in the city.

About a decade after they arrived, the congregation decided it was time to move. Tough economic conditions in Leiden meant few new recruits from England were willing to join them; Dutch culture was thought to be a bad influence on the children; and there was a looming possibility that Holland would go to war with Spain, a leading Catholic power.

Leaving Leiden University. NASA Earth Observatory image by Joshua Stevens, using Landsat data from the U.S. Geological Survey.

Leiden was a city of many waterways, so when the Pilgrims were ready to leave in July 1620, they boarded several small boats on the Rapenburg Canal (near the university). This narrow canal fed into the larger Vliet Canal, which flows from Leiden toward Delft.

From there, they made their way back to England, where they struggled for a few months trying to repair a leaking ship. After abandoning that ship, they finally set sail for the New World on September 6, 1620, knowing they had to cross nearly 3,000 miles of open ocean.

The North Atlantic can be treacherous. Image credit: NASA Earth Observatory image by Jesse Allen and Robert Simmon, using VIIRS data from the Suomi National Polar-orbiting Partnership.

The original destination: the mouth of the Hudson River. NASA Earth Observatory image by Jesse Allen, using Landsat data from the U.S. Geological Survey.

The first half of the two month journey proved to be smooth and uneventful. But in October, they encountered a series of storms that turned the sea into a writhing cauldron. During one particularly bad storm, the ship nearly capsized.

Their intended destination was the northern edge of Virginia Colony, which at the time stretched from to the mouth of the Hudson River. However, the storms blew the Pilgrims off course toward Cape Cod in Massachusetts.

Provincetown, Massachusetts. NASA Earth Observatory image by Jesse Allen, using Landsat data from the U.S. Geological Survey.

When they realized this, they contemplated heading south. However, they were wary of the shallow waters and shoals east and south of Cape Cod and Nantucket—waters full of the sandy, rocky outwash from ancient glaciers. They sailed instead around the northeastern tip of the Cape and on November 21, 1620, dropped anchor just off the shores of modern-day Provincetown. While resting in that harbor, they composed and signed the first self-governing document in American history, the Mayflower Compact.

Over the coming weeks, they made first contact with Native American people, likely the Nauset tribe. First Encounter Beach in Eastham marks the reported location of a skirmish between the colonists and the tribe. The Pilgrims eventually sailed across Cape Cod Bay and settled in Plymouth.

First Encounter Beach. NASA Earth Observatory image by Jesse Allen, using Landsat data from the U.S. Geological Survey.

It was in Plymouth where the Pilgrims celebrated the first Thanksgiving, a three-day harvest celebration that included feasting, games, and military exercises.

While there continues to be debate among historians about the circumstances and influences that led to the first Thanksgiving, there is evidence that the roots of the tradition might be traced back to Leiden. During their time in the city, the Pilgrims would have experienced a celebratory thanksgiving service and festival that was held each year on October 3 to mark the 1574 end of the Spanish siege of the city.

Crossing Cape Cod Bay brought the Pilgrims to Plymouth. This astronaut photograph was acquired on November 7, 2007.


The Unsung Woman Who Discovered an Unknown Island

August 22nd, 2018 by Kasha Patel

Betty Fleming, a cartographer, helped discover tiny Landsat Island with satellite imagery in the 1970s. Photo courtesy of Betty Fleming.

At age 86, Betty Fleming was on a cruise along the Labrador Coast of Canada. The ship was approaching an area all too familiar to her: a small island she helped discover when she was a cartographer for the Surveys and Mapping branch in Canada’s Department of Energy, Mines, and Resources.

“I want to tell you about a small off-shore island that we will be passing as we round the top end of Labrador on this trip,” wrote Fleming in her notes, which she used to deliver a presentation to her 90 fellow passengers on her leisure Adventure Canada cruise. “Landsat Island has garnered quite a bit of attention since it was first mapped in 1976. Don’t expect to see it though, as it is in the middle of an area of reefs and shoals.”

More than 45 years ago, Fleming was surveying the same waters, but via satellite imagery from the Landsat 1 satellite. Earth Resources Technology Satellite 1, later named Landsat, was an early Earth-sensing satellite launched by the United States. Before the satellite even launched, Canada built a receiving station to receive the satellite data for the orbits over Canada.

Aerial image of Landsat Island taken by David Gray on August 2, 1997.

Aerial image of Landsat Island taken by David Gray on August 2, 1997.

This satellite image of Landsat Island captured on July 15, 2014, by the Operational Land Imager (OLI) on Landsat 8. The island spans no more than a pixel or two. Image credit: NASA Earth Observatory/Joshua Stevens

This satellite image of Landsat Island captured on July 15, 2014, by the Operational Land Imager (OLI) on Landsat 8. The island spans no more than a pixel or two. Image credit: NASA Earth Observatory/Joshua Stevens

The 1970s was an exciting time for Fleming, as acquiring and analyzing satellite imagery was new and thrilling. As Canada received imagery from Landsat roughly every two weeks, Fleming had the task of seeing where the Department of Energy, Mines and Resources might use the imagery for mapping Canada, particularly for mapping wilderness areas and building new roads. At the time, the hydrographic charts for the northern coast of Labrador were also quite old and based on surveys by the British Navy in 1911 and on questionable notes made by passing sailors.

In those early Landsat days, Fleming was inspecting imagery of the coast from Landsat 1 when she spotted several small white specks. At first, she assumed they were icebergs, but some of the specks kept appearing in the same position over several images. She knew some of them had to be permanent features.

Landsat coverage of the survey area showing the overlap of the satellite images. The land area tended to be cloud-covered, forcing the selection of control points to the narrow coastal band as shown. Image courtesy of Betty Fleming.

Landsat coverage of the survey area showing the overlap of the satellite images. The land area tended to be cloud-covered, forcing the selection of control points to the narrow coastal band as shown. Image courtesy of Betty Fleming.

She passed the information to the Canadian Hydrographic Survey Division, which sent the CCS Baffin to visit about 20 such locations in the following summer. Most of the locations were insignificant rocks partly submerged in the sea—Fleming called them “rocks awash”– but one of the spots was actually an island. Fleming and the Landsat satellite had discovered an uncharted Canadian island. It eventually became known as Landsat Island.

CSS Baffin survey of the coast of Labrador from 59°15'N to 60° 25'N during 1976 to chart offshore features and check reported rocks. Image courtesy of Betty Fleming.

CSS Baffin survey of the coast of Labrador from 59°15’N to 60° 25’N during 1976 to chart offshore features and check reported rocks. Image courtesy of Betty Fleming.

Landsat Island was not too spectacular. It was rocky and only about half the size of a football field. From a satellite perspective, though, this island was notable because of its size – or rather lack of it. Earth science researchers were impressed that a satellite could detect such a small feature. The island was also interesting, says Fleming, because it had a bearing on the international boundary: it was the most easterly point of land at that part of the coast.

Fleming has never seen Landsat Island and does not expect to. She never went out on the ships or helicopters that were sent to verify the existence of the island. That section of the Labrador coast is “very dangerous,” and her tourist cruise in 2011 is probably the closest she is going to get to the place she discovered.

But that doesn’t faze her. Her accomplishments go beyond one island. Before her stint analyzing Landsat data, she was a pilot and camera operator. She studied at the newly formed Netherlands International Training Centre for Aerial Photography and Earth Sciences and became a specialist on the application of aerial photography to photogrammetric mapping—using photographs to measure and map areas. She also instituted a index map where images could be ordered by orbit number and image number, which was used in Canada.

Then there was simply being a working woman from the 1950s to 1980s, which Fleming says is a story in itself. As a married woman, she too-often ran into people who told her “You’ll leave to have a baby,” or “You’ll take a job from a man.”

When she chose to enter the all-male Surveys and Mapping Department, she had an entry level job at which they hired boys out of high school—despite the fact she had a university degree, post-graduate training, and experience in the aerial survey business. She always used the name “E.A. Fleming” when she prepared a technical paper because “using the name Elizabeth on any technical paper would have been a kiss of death. It would immediately be dropped in the editor’s waste basket without opening it.” She won several awards for her published papers, much to the chagrin of one man who did not find out she was a woman until she accepted an award.

“It took me 20 years to get to the level I should have been hired at, but that doesn’t change the fact that I really enjoyed my work,” wrote Fleming.

After a 30 year-long career in aerial photography and mapping and two happy marriages, Fleming is now retired at the age of 93 and resides in Ottawa, Canada.

Read more at:

The Island Named After a Satellite (NASA Earth Observatory)

Landsat Island (NASA Landsat Science)

The Telstar satellite (left) and the 1974 Telstar Durlast, the official ball of the 1974 World Cup. Image Credit: Bell Labs/Shine 2010

Goooooooal!!!! The 2018 FIFA World Cup kicked off on June 14, 2018.

Here’s a bit of Cup trivia you may not know. In 1962, NASA launched a small, spherical communications satellite called Telstar that ended up altering the look of the balls used in the World Cup.

Telstar was the first active communications satellite and the first commercial payload in space. By sending television signals, telephone calls, and fax images from space, the 3-foot-long satellite kicked off a whole new era in telecommunications—and soccer ball design.

There’s a direct line between the distinctive black and white patterning of Telstar’s hull and solar panels and the Adidas ball used as the official ball of the 1970 World Cup in Mexico and the 1974 World Cup in West Germany. While earlier generations of soccer balls were brown and did not show up well on television, the 1970 and 1974 balls featured the now iconic 32-panel design of alternating white hexagons and black pentagons, a pattern that closely resembled Telstar. Fittingly, that first ball was called Telstar Elast; the official ball in 2018, a nod to the 1970 ball, is called the Telstar 18.

To celebrate the World Cup, Earth Observatory is planning to dig into its archives. For key games, we’ll grab one image for each of the two countries going head to head. Can you guess which image goes with which country? Just click on the images below to find out. Enjoy the tournament!

June 14:
Russia  5  — 0  Saudi Arabia


June 15
Uruguay  1 — 0 Egypt


Iran 1 — 0  Morocco


Portugal 3 — 3 Spain


June 16
France 2 — 1 Australia


Iceland 1 — 1 Argentina

Peru 0 — 1 Denmark


Croatia 2 — 0 Nigeria

June 17
Costa Rica 0 — 1 Serbia

Brazil 1 — 1 Switzerland

Mexico 1 — 0 Germany


June 18
Sweden vs. Korea Republic


Belgium vs. Panama

Tunisia vs. England