Earth News

Northern California ushered in 2006 with a series of major storms that inundated the area and left many towns awash in water, mud, and debris. According to a report from the USATODAY.com Website, at least two levees in the Sacramento-San Joaquin Delta region were unable to handle the rising waters and strong winds, and residents nearby evacuated as the water-control structures began leaking. In the wine-country town of Napa perhaps as many as 1,000 homes were flooded along with thousands of acres of rural and agricultural land. The governor declared several counties in the region flood disaster areas.

This pair of images shows flooding in the Sacramento-San Joaquin Valley region inland of San Francisco Bay. The image on the left was captured by the Moderate Resolution Imaging Spectroradiometer (MODIS) on NASA’s Aqua satellite on December 10, 2005, while the image at right was captured on January 4, 2006, just days after the severe storms passed through. Dark blue pools of water swamp far larger areas of ground in January than they did in December. The Sacramento River is very wide and turbid; the sediment in the water is reflective and gives the river its lighter blue appearance. The northern reaches of San Francisco Bay are also bright with sediment, which may be a mixture of river run-off and churning of the Bay by storm winds. Vegetation is bright green, snow in the Sierra Nevada Mountains is bright blue (upper right), and bare or sparsely vegetated ground appears pinkish or reddish tan.

The rain-producing storms that passed through the state became blizzards as they crossed the mountains. A wider-area image produced by the MODIS Rapid Response Team shows snow cover on the Sierra Nevada Mountains and across the Great Basin.

NASA image courtesy the MODIS Rapid Response Team, Goddard Space Flight Center

In late November 2005, Aoba (locally called Mt. Manaro) Volcano on Ambae Island in the South Pacific began rumbling, threatening a dangerous eruption. About 5,000 people, half the island’s population, were evacuated in early December when the volcano started spewing clouds of steam and toxic gases as molten material entered Lake Voui, which fills the volcano’s crater. According to reports on the Smithsonian Global Volcanism Website, the contact of the molten material with the lake water produced a plume of steam and gas that rose 3.9 to 4.5 kilometers (12,800-14,800 feet) above sea level. The eruption created an island within the lake that is about 200 meters wide and 50-60 meters high.

Aoba Volcano is the dominant feature in this shaded-relief image of Ambae Island, part of the Vanuatu archipelago, which includes more than 80 islands in the South Pacific located about three-quarters of the way from Hawaii to Australia. Last active in 1996, the 1,496-meter (4,908-foot), Hawaiian-style, basaltic shield volcano has lakes within its summit caldera, or crater. The November-December eruption involved a vent at the center of Lake Voui (at left), which was formed approximately 425 years ago after an explosive eruption.

Two visualization methods were combined to produce the image: shading and color coding of topographic height. The shading indicates direction of the slopes; northwest slopes appear bright, while southeast slopes appear dark. Color coding shows height, with green at the lower elevations, rising through yellow and tan, to white at the highest elevations. The volcano is not perfectly cone-shaped, but is elongated in a northeast-to-southwest direction. The island is dotted with outcrops of scoria, a glassy lava rock riddled with bubbles created by volcanic gases escaping the rock during eruptions. The flattened-looking summit shows that the newest crater is actually nested within older, larger craters.

Elevation data used in this image were acquired by the Shuttle Radar Topography Mission (SRTM) aboard the Space Shuttle Endeavour, launched on February 11, 2000. SRTM used the same radar instrument that comprised the Spaceborne Imaging Radar-C/X-Band Synthetic Aperture Radar (SIR-C/X-SAR) that flew twice on the Space Shuttle Endeavour in 1994. SRTM was designed to collect 3-D measurements of the Earth’s surface. To collect the 3-D data, engineers added a 60-meter (approximately 200-foot) mast, installed additional C-band and X-band antennas, and improved tracking and navigation devices. The mission is a cooperative project between NASA, the National Geospatial-Intelligence Agency (NGA) of the U.S. Department of Defense and the German and Italian space agencies. It is managed by NASA’s Jet Propulsion Laboratory (JPL), Pasadena, Calif., for NASA’s Earth Science Enterprise, Washington, D.C.

NASA image courtesy JPL and NGA

Nearly six years of regional drought and rapidly increasing demand for water have resulted in decreasing water levels in lakes throughout East Africa. Water levels in Africa’s largest lake, Lake Victoria, have dropped by about 1 meter (3 feet) over the past 10 years. The drought has similarly impacted the source regions of the Nile River, reducing water flows downstream into Egypt and Lake Nasser.

This pair of images documents recent drops in water levels in the Toshka Lakes region of Egypt. The Toshka Lakes and the New Valley surrounding the lakes constitute a major Egyptian project to claim a huge area of desert for agriculture and industry by diverting Nile River water from Lake Nasser . The initial flooding occurred in the late 1990s, when Lake Nasser water levels were at an all-time high. The flooded regions of the Toshka Lakes west of Lake Nasser have decreased greatly over the years, exposing the former dune fields (dunes appear as islands in the lake and along the shoreline of the top image), and leaving a “bath-tub ring” of wetlands (dark region) surrounding the lake shorelines. As both the drought and development continue, this region of Egypt is sure to change.

Astronaut photograph ISS012-E-11639 was acquired December 11, 2005, with a Kodak 760C digital camera using an 180 mm lens, and is provided by the ISS Crew Earth Observations experiment and the Image Science & Analysis Group, Johnson Space Center. The earlier image, STS102-716-25, was taken from the Space Shuttle on March 15, 2001 using a Hasselblad film camera equipped with a 250 mm lens. The International Space Station Program supports the laboratory to help astronauts take pictures of Earth that will be of the greatest value to scientists and the public, and to make those images freely available on the Internet. Additional images taken by astronauts and cosmonauts can be viewed at the NASA/JSC Gateway to Astronaut Photography of Earth.

On October 8, 2005, a large earthquake shook the mountainous Kashmir region near the border of Pakistan and India. Tens of thousands of people died, and many more were isolated in the mountains by damage to roads and bridges as well as by landslides. Heavy winter snowfall poses an additional threat to millions of survivors made homeless by the quake.

In the first week of January 2006, a new snow storm blanketed the mountains of Pakistan, including the region around the epicenter of the quake. This image from the Moderate Resolution Imaging Spectroradiometer (MODIS) on NASA’s Aqua satellite shows snow highlighting the ridges and ravines in the mountains northeast of the city of Islamabad on January 6. According to news reports on the BBC Website, the snow is hampering aid efforts to some areas, and avalanches triggered by earthquake aftershocks continue to threaten people in some mountainous areas.

NASA image created by Jesse Allen, Earth Observatory, using data obtained courtesy of the MODIS Rapid Response team.

Tropical Cyclone Clare is a moderately strong storm system in the Indian Ocean off the Australian coast. When the Moderate Resolution Imaging Spectroradiometer (MODIS) on the Aqua satellite observed the cyclone at 06:05 UTC (2:05 p.m. local time) on January 9, 2006, it was a well-developed system with peak sustained winds of around 100 kilometers per hour (60 miles per hour). The cyclone (the local term for a hurricane or typhoon) was about 200 kilometers offshore from Port Hedland in Western Australia, the nearest major city.

NASA image created by Jesse Allen, Earth Observatory, using data obtained courtesy of the MODIS Rapid Response team.

On January 2, 2006, winds whipped a fast-moving fire across the grasslands just south of the Red River, which marks the border between Oklahoma and Texas. According to reports from the Associated Press, the fire nearly razed the small ranch town of Ringgold, Texas, destroying as many as 50 homes and most of the buildings along the small town’s Main Street. The fire scorched tens of thousands of acres between Ringgold and the town of Nocona, to the southeast.

The charcoal-colored burn scar slices through the center of this image, captured on January 8, 2006, by the Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) on NASA’s Terra satellite. To make the burn scar stand out more prominently, the image was enhanced with the sensor’s observations of near- and shortwave-infrared energy as well as visible light. Winter-bare ground is tan and brown, while patches of red indicate growing vegetation, probably irrigated crops. The small town of Nocona appears as a cement-gray splash at lower right of the scene, while the location of Ringgold is obscured by a cloud at image left.

According to the U.S. Drought Monitor map for January 3, drought stretched across the south-central United States in the first of January, affecting Arizona, southern Colorado, New Mexico, Texas, Oklahoma, and western Arkansas. A pocket of Exceptional Drought—the highest drought category on the scale—spanned northeastern Texas, southeastern Oklahoma, and intruded a short distance into western Arkansas. The lack of rain, high temperatures, and strong winds were a menace for firefighters across the region, who continued to battle grassland and other wildfires through the first part of the month.

NASA image created by Jesse Allen, Earth Observatory, using data provided courtesy of the NASA/GSFC/METI/ERSDAC/JAROS and U.S./Japan ASTER Science Team

The bitter cold of winter settled ferociously over the interior of Asia during the first week of 2006. A large mass of Siberian air swept as far south as India and as far east as Japan, enveloping much of Asia with uncommonly low temperatures. In many places, the cold weather was accompanied by crippling snow. Among the most severely affected were the 200,000-plus people stranded in northwestern China when heavy snow fell over the region, reported United Press International. The cold snap also levied a heavy toll on northern India, where an estimated 200 had died of the cold as of January 9, said the BBC.

The effect of the cold air on the land can be seen in these land surface temperature images, taken by the Moderate Resolution Imaging Spectroradiometer ( MODIS ) on the Terra satellite between January 1 and January 8. Unlike the air temperatures given in weather reports, which tell how cold the air near the Earth is, land surface temperature measurements record how cold the ground is. In these images, land temperatures are represented with color, deep blue being the coldest temperatures and yellow being the warmest.

In January 2006 (top), large sections of China were significantly colder than they were in 2005 (bottom). The Taklimakan Desert formed a warm pink and purple oval surrounded by the cold blue of the Kunlun Shan and Tian Shan mountain ranges in the 2005 image. One year later, the desert is the dark blue of intense cold. To the north of the desert, where most of the people affected by snow in China live, the warmer purple tones that marbled the region in 2005 are gone, replaced with colder blue tones. In both images, areas that were cloudy throughout the eight-day period are gray.

NASA image created by Jesse Allen, Earth Observatory, using data provided courtesy of Z. Wan, MODIS Land Science Team.

Just a few kilometers inland from the North Sea coast of Belgium lies the popular tourist city Bruge (spelled Brugge in Flemish, and sometimes also in English). Its popularity stems from a stunning collection of architecture, canals, and art dating from medieval times. At one time Bruge was a major center of trade, but it suffered a gradual economic decline through the 1500s. The city’s “neglect” became a major asset in the modern era of easy global travel and tourism. Today, millions visit the city each year to enjoy the extraordinarily well-preserved feel of a town reaching back through centuries of history.

This natural-color Landsat 7 image was collected by the Enhanced Thematic Mapper Plus (ETM+) instrument on May 23, 2001. The modern city of Bruge appears in the image as a grey area with a roughly circular center that is ringed by a canal, which was made by the reshaping of the Reie River. This canal encircles the limits of the old city, and it connects to smaller canals threading through the city. The ring canal connects with the Zwin River to the northeast at Damme. Near the coast, the very large, Y-shaped, Boundewijn Canal leads north to the port of Zeebruge and to the North Sea. Surrounding Bruge is the Flanders countryside, a very flat, fertile plain. The fields make a tan and green checkerboard.

The rivers and canals are directly related to the rise and fall of the prominence of Bruge. The town already existed in 1134 when a storm flooded the coastal plains and dramatically reshaped Flanders. The storm scoured a deep passage in the existing Zwin River which ran near Bruge, giving access to the North Sea. The connection to the sea allowed Bruge to rapidly develop into a major center for export of goods from throughout Europe. Through the 1200s to the 1500s, Bruge’s economy continued to grow.

However, the flatness of the plains of Flanders meant that the Zwin River was not a swift-flowing river. Eventually silt deposits began to choke the Damme and Bruge port facilities, and the city fell into economic decline. While it continued to be an important city for some time to come, other cities with better port access came to dominate.

By the early 20th century, Bruge was a relatively quiet city. King Leopold ordered a major new canal to reshape the Zwin River and connect it to Bruge through a new major canal. This effort also created a new port city on the modern coastline, Zeebruge (roughly translated, “Bruge on the Sea”). However, the prevalence of railway transportation by this time meant that Zeebruge did not revitalize the city in the manner that the 1134 storm had done.

NASA image created by Jesse Allen, Earth Observatory, using data obtained courtesy of the University of Maryland’s Global Land Cover Facility .

Dry conditions and high winds have lead to numerous recent fire outbreaks throughout much of the southwestern and south-central USA. Drought conditions have persisted in the region for months, leading to a build-up of fire fuels, including dried grasses, shrubs, and trees. The combination of high amounts of dry fuel and frequent high winds has stoked small fires into widespread brush fires.

This astronaut photograph captures a 25-kilometer long smoke plume from a fire in the Upper Ouachita National Wildlife Refuge in northeastern Louisiana. The fire started at approximately 1:00 p.m. on January 2, 2006, and this image was acquired approximately three and a half hours later as the International Space Station passed over the Texas-Louisiana border, to the southwest of the scene. The long extent of the plume reflects the strong westerly winds that drove the fire eastwards and damaged an estimated 200-300 acres of the wildlife refuge. The striking illumination of the plume is caused by a very low sun angle (the angle between the horizon and the Sun at the point on the ground directly below the Space Station). Although the plume is well illuminated, the low sun angle results in low illumination of other scene features, such as agricultural fields adjacent to the refuge.

The Moderate Resolution Imaging Spectroradiometer (MODIS) on NASA’s Aqua satellite captured an image of the area six days after the photo from the crew of the International Space Station. That image shows the burn scar from the Ouachita fire to the left of center as well as two, new, active fires.

Astronaut photograph ISS012-E-13692 was acquired January 2, 2006, with a Kodak 760C digital camera using a 400 mm lens, and is provided by the ISS Crew Earth Observations experiment and the Image Science & Analysis Group, Johnson Space Center. The International Space Station Program supports the laboratory to help astronauts take pictures of Earth that will be of the greatest value to scientists and the public, and to make those images freely available on the Internet. Additional images taken by astronauts and cosmonauts can be viewed at the NASA/JSC Gateway to Astronaut Photography of Earth.

Though Cyclone Clare caused little damage when it initially came ashore over northwestern Australia on January 10, 2006, it triggered widespread flooding as it moved south across Western Australia. The floods forced the government to declare disaster areas in at least three communities in southwestern Australia.

The Moderate Resolution Imaging Spectroradiometer ( MODIS ) on NASA’s Aqua satellite captured the top image of flooding in the typically dry Murchison River basin on January 15, 2006. The river is the second longest in Western Australia, but water normally only flows in it during the summer cyclone season. The rest of the year, the river is a dry sand channel as shown in the lower image, taken by Aqua MODIS on December 26, 2005. The communities most affected by the flooding are south of the area shown in these images.

These images were generated by the MODIS Rapid Response Team, which provides daily images of the region.

NASA image courtesy the MODIS Rapid Response Team at Goddard Space Flight Center.

Augustine Volcano, in the Cook Inlet of the Gulf of Alaska, erupted on January 13 and 14, 2006. According to the Alaska Volcano Observatory (AVO) , these explosive eruptions produced clouds of volcanic ash and flows of mud and rock fragments. Although more eruptions were not certain to occur as of January 17, 2006, the volcano could be expected to erupt again without warning. Based on eruptions observed in 1976 and 1986, observers at the AVO anticipated that eruptions might continue for a period of several days to a few weeks.

The Moderate Resolution Imaging Spectroradiometer (MODIS) flying onboard the Aqua satellite captured this image on January 13, 2006. In this image, a discernible steam and ash plume streams from the small volcanic island and heads eastward over the ocean. The brown and white cloud of material in the middle of the image is likely composed of volcanic material from Augustine. To the east, a distinct cloud formation appears. Land surface areas are covered with snow, although the volcanic island looks darker, as if its own snow cover has melted or been buried by volcanic debris.

Augustine is a 1,260-meter-tall (4,134-foot-tall), cone-shaped volcano built from alternating layers of ash, lava, and rock fragments. It has historically been the most active volcano in the Cook Inlet area, experiencing eruptions throughout the 19th and 20th centuries. This volcano experienced some unrest in December 2005.

Further Reading:

Augustine Volcano from the Alaska Volcano Observatory

NASA image created by Jesse Allen, Earth Observatory, using data obtained from the Goddard Earth Sciences DAAC .

Named after American Antarctic explorer Richard E. Byrd, West Antarctica’s Byrd Glacier flows through a deep valley in the Transantarctic Mountains, covering a distance of 180 kilometers (112 miles) and descending more than 1,300 meters (4,300 feet) as it flows into the Ross Ice Shelf. The fast-moving stream is one of the largest contributors to the shelf’s total ice volume.

This pair of satellite images shows the Byrd Glacier with low contrast (top) and high contrast (bottom). The low-contrast version is similar to the level of detail the naked eye would see in an airplane flight over the area. In this scene, the ice sheet seems smooth and almost featureless. The bottom image uses enhanced contrast to highlight flow lines on the ice sheet and bottom crevasses. Bottom crevasses are cracks in the ice that form in the underside of the ice surface. Locating such crevasses through satellite imagery can help ensure the safety of researchers on the ground. The high-contrast version also accentuates the ruggedness of the mountains that surround the glacier.

These images are part of the MODIS Mosaic of Antarctica data set. Researchers at the National Snow and Ice Data Center and the University of New Hampshire compiled the map from 260 images of Antarctica acquired by the Moderate Resolution Imaging Spectroradiometer (MODIS) sensors on NASA’s Terra and Aqua satellites between November 20, 2003, and February 29, 2004. Available through the National Snow and Ice Data Center’s Website, a map server enables anyone interested in MOA data to generate images from the map at different levels of magnification and contrast.

Further Reading:

Mosaic of Antarctica from the Earth Observatory

Mosaic of Antarctica imagery download and documentation from the National Snow and Ice Data Center

State of the Cryosphere from the National Snow and Ice Data Center

Byrd Glacier Exhibit from Goddard Space Flight Center’s Scientific Visualization Studio

Image courtesy the National Snow and Ice Data Center, based on data from NASA’s Aqua and Terra MODIS sensors.

Along the margin of the Greenland Ice Sheet, outlet glaciers flow as icy rivers through narrow fjords and out to sea. As long as the thickness of the glacier and the depth of the water allow the ice to remain grounded, it stays intact. Where the ice becomes too thin or the water too deep, the edge floats and rapidly crumbles into icebergs. Satellite observations of eastern Greenland’s Helheim Glacier show that the position of the iceberg’s calving front, or margin, has undergone rapid and dramatic change since 2001, and the glacier’s flow to the sea has sped up as well.

These images from the Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) on NASA’s Terra satellite show the Helheim glacier in June 2005 (top), July 2003 (middle), and May 2001 (bottom). The glacier occupies the left part of the images, while large and small icebergs pack the narrow fjord in the right part of the images. Bare ground appears brown or tan, while vegetation appears in shades of red.

From the 1970s until about 2001, the position of the glacier’s margin changed little. But between 2001 and 2005, the margin retreated landward about 7.5 kilometers (4.7 miles), and its speed increased from 8 to 11 kilometers per year. Between 2001 and 2003, the glacier also thinned by up to 40 meters (about 131 feet). Scientists believe the retreat of the ice margin plays a big role in the glacier’s acceleration. As the margin of the glacier retreats back toward land, the mass of grounded ice that once acted like a brake on the glacier’s speed is released, allowing the glacier to speed up.

Overall, the margins of the Greenland Ice Sheet have been thinning by tens of meters over the last decade. At least part of the thinning is because warmer temperatures are causing the ice sheet to melt. But the other part of the thinning may be due to changes such as glacier acceleration like that seen at Helheim. Initial melting due to warming may set up a chain reaction that leads to further thinning: the edge of the glacier melts and thins, becomes ungrounded and rapidly disintegrates. The ice margin retreats, the glacier speeds up, and increased calving causes additional thinning. Understanding the dynamic interactions between temperature, glacier flow rates, and ice thickness is crucial for scientists trying to predict how the Greenland Ice Sheet will respond to continued climate change.

Reference

Howat, I. M., I. Joughin, S. Tulaczyk, and S. Gogineni (2005). Rapid retreat and acceleration of Helheim Glacier, east Greenland. Geophysical Research Letters, 32, L22502, doi:10.1029/2005GL024737.

Further Reading:

Press release on the retreat of the Helheim Glacier

NASA images created by Jesse Allen, Earth Observatory, using data provided courtesy of NASA/GSFC/METI/ERSDAC/JAROS, and the U.S./Japan ASTER Science Team.

In northern Tunisia near the shore of the Mediterranean Sea, the lake and wetlands of Ichkeul National Park are an important stopping-over point for hundreds of thousands of migrating birds each year. Among the lake’s visitors are ducks, geese, storks, and pink flamingoes. The park is on the United Nations Educational, Scientific, and Cultural Organization’s (UNESCO) list of World Heritage sites, and since 1996, the park has also been on the group’s List of World Heritage Sites in Danger. Dam construction on the lake’s feeder rivers has produced major changes to the ecological balance of the lake and wetlands.

The pair of satellite images above shows changes in the lake level and aquatic vegetation between November 14, 2001 (top), and July 29, 2005 (bottom). Vegetation appears red, bare or thinly vegetated ground is tan, and water is blue. Although the lake level is higher in 2005 than in 2001, a large part of the lake appears red due to the presence of aquatic plants. Because dams have sharply reduced the freshwater inflow to the lakes and marshes, reed beds, sedges, and other fresh-water plant species have been replaced with salt-loving plants. These changes have produced a sharp reduction in the migratory bird populations, which depended on the mix of plants that used to exist.

According to the UNESCO Website, the Tunisian government has undertaken some steps to retain freshwater and reduce salinity, but some reports from the World Conservation Union suggest that the salinity has already become excessively high and the possibility for rehabilitation may be rapidly disappearing.

The large images each cover an area of 11.4 by 20.0 kilometers, and they are centered near 37.1 degrees North, 9.7 degrees East.

Image courtesy NASA/GSFC/METI/ERSDAC/JAROS, and the U.S./Japan ASTER Science Team

Widespread drought in eastern Africa has withered the grass and other vegetation of northern Tanzanias famous Serengeti Plain in January 2006. The rainy season should have begun around October (2005), but by mid-January, had failed to arrive. According to some news reports, the severe drought created great stress among the Seregetis migrating wildlife, including wildebeest and zebras, as well as less nomadic animals such as giraffes.

This pair of images from the Moderate Resolution Imaging Spectroradiometer ( MODIS ) on NASA’s Terra satellite shows the parched, brown landscape on January 9, 2006 (top), compared to January 12, 2005 (bottom). The region appears desert-like in 2006 compared to the green vegetation which blanketed the area in 2005. Lakes Eyasi and Manyara (lower right) appear to be completely dry.

The conditions shown in this image have been developing over several seasons. Eastern Africa receives most of its rainfall during the long rainy season between March and May, with additional rain during the short rainy season from October to December. In 2005, both seasons failed. As a result, rainfall totals for the year were only 20-60 percent of normal, depending on the region, reported the Famine Early Warning Network (FEWS NET). “This drought has resulted in crop failures, pasture degradation, water shortages and has raised serious food security concerns for the region,” FEWS NET warned. The drop of water levels in regional water levels also impacted the region’s energy supply, which depends largely on hydroelectric power, said news reports.

NASA images courtesy the MODIS Rapid Response Team at NASA GSFC.

Approximately 160 kilometers (100 miles) southwest of London, the city of Bath in southwest England has made history in several ways. Underlain by Britain’s only hot mineral springs, the city was built as a spa at least as early as the Roman era, and perhaps earlier, drawing thousands of visitors over the centuries who hoped for cures the waters might provide. The city was the site of various battles from Anglo-Saxon era, around the 7th century, to modern times. On a more genteel note, it was home to Jane Austen for several years. Yet Bath has made another important contribution to history, namely in the making of geologic maps. Arguably the world’s first published geologic map, released at the end of the 18th century, covered the area around Bath.

The Enhanced Thematic Mapper Plus (ETM+) instrument on NASA’s Landsat satellite captured this photo-like image of Bath on April 4, 2002. The city appears as a grayish splotch sprawling through the mostly green landscape. Surrounding the city are fields of variegated green dotted with occasional patches of tan. The River Avon meanders through the center of town. Until recently, this river—once a network of braided streams—periodically flooded parts of the city. The construction of flood-control structures made it more manageable. Over time, rivers can change course, leaving behind dried-up riverbeds. The wormlike, charcoal-colored features in the right half of the image could be old river channels. Lying at the bottom of the Avon Valley, the city of Bath is surrounded by limestone hills.

Bath had certainly seen its share of maps by 1799, but not the new kind of map published that year. As Simon Winchester recounted in The Map that Changed the World , the budding geologist William Smith mapped the area in a way it hadn’t been mapped before. In fact, no place had. Inspired by an agricultural map, and by his own experiences in mining and fossil collecting, Smith decided to draft a map of the area showing what was below the surface—the rock types underneath the buildings, farms, and trees. Titled A Map of Five Miles round the City of Bath, on a scale of one inch and a half to a mile, from an Actual Survey, including all the new roads, with Alternations and Improvements to the present time, 1799 , it was arguably the first geologic map ever published. Smith developed a color code for the rock types that is still in use today. He went on to publish a geologic map of England, Wales, and part of Scotland in 1815. Today, NASA satellite data continue to extend the modern era of map making started by Smith.

This particular map might not have led to any outburst of activity at the time, but geologic maps quickly assumed an important role in science and commerce. Nineteenth-century England relied heavily on coal for power, and knowing where to find the remains of ancient swamps that would yield this fossil fuel saved miners precious time and money. Fossil fuels aside, geologic maps also play an important role in locating earthquake faults and landslides.

The year 1799 proved to be an important one for Earth science, besides the publication of the map of Bath. The same year, Smith and two friends, Joseph Townsend and Benjamin Richardson, recognized what is now known as the Permo-Triassic Boundary . This part of Earth’s rock record marks the most catastrophic extinction so far identified in our planet’s history. The same year, famous fossil hunter Mary Anning was born.

Further Reading:

Winchester, S. (2001) The Map that Changed the World. Harper Collins, New York, New York.

NASA image created by Jesse Allen, Earth Observatory, using Landsat data obtained courtesy of the University of Maryland’s Global Land Cover Facility .