Day after day of stormy weather has lead to flooding, mudslides and huge snowfall totals across California. Well over 10 feet of snow has fallen across much of the Sierra Nevada, and over 2 feet of rain was reported in the San Gabriel Mountains northeast of Los Angeles. To blame is the steady stream of moisture being brought up from the subtropics from near Hawaii by the subtropical jet steam known as the “Pineapple Express.†The Pineapple Express can also interact with storm systems rotating around a large, persistent upper-level low-pressure system off the West Coast, as in the current situation. Additionally, mountainous topography is effective in squeezing out even more moisture in the form of steady precipitation as the warm, moisture-laden air rides up and over the slopes.
The TRMM-based, near-real-time Multi-satellite Precipitation Analysis (MPA) at NASA’s Goddard Space Flight Center monitors rainfall over the global Tropics. Here MPA rainfall totals are shown for the period from January 6 - 11, 2005. The red areas just off of the coast indicate the highest totals of more than 225 mm (about 9 inches) of rainfall. Coastal areas of southern California including Los Angeles and San Diego generally received between 4 and 7 inches of rain (orange areas) for the period.
TRMM is a joint mission between NASA and the Japanese space agency JAXA.
Image and animations produced by Hal Pierce (SSAI/NASA GSFC) and caption by Steve Lang (SSAI/NASA GSFC).
posted to Earth News. at Wed Jan 12 15:23:07 -0500 2005.
Late in the dry season near the mouth of the Amazon River in Brazil, numerous fires were burning when the Moderate Resolution Imaging Spectroradiometer (MODIS) on NASA’s Aqua satellite captured this image on November 22, 2004. Locations where MODIS detected active fires are marked in red. It’s surprising to many people that the Amazon Rainforest even has a dry season, but in fact there are places that go months each year with little or no rain. In this part of the Amazon, the rainy season won’t get fully underway until January.
Before widespread human settlement and agricultural development in and around the Amazon, forest fires were extremely rare: an area might have experienced fire once every few centuries. The forest survives the dry season by tapping water many meters down in the soil, and there were few natural triggers for fires becuase lightning is almost always accompanied by rain. Today, the forests are under pressure from both intentional and accidental fires caused by humans. For more about how fire is changing the Amazon Rainforest, please read the feature story “From Forest to Field.â€
NASA image created by Jesse Allen, Earth Observatory, using data obtained from the MODIS Rapid Response team.
posted to Earth News. at Wed Nov 24 20:09:31 -0500 2004.
Typhoon Muifa spins off the eastern shore of Luzon in this Moderate Resolution Imaging Spectroradiometer (MODIS) image, acquired on November 17, 2004 by NASA’s Aqua satellite. The storm has already drenched the Philippine island of Catanduanes, causing floods and landslides, and is expected to turn west and cross over Luzon before the end of the week. Muifa reached typhoon status at about the time this image was taken at 4:55 UTC. By 12:00 UTC, the storm’s winds reached 139 kilometers per hour (86 mph) with gusts up to 167 kph (103 mph).
NASA image courtesy Jeff Schmaltz, MODIS Land Rapid Response Team at NASA GSFC
posted to Earth News. at Wed Nov 17 22:07:45 -0500 2004.
In a typical monsoon season in South East Asia, the rains fall until October, but this year, the heavens went dry three to four weeks early. For farmers, who rely on monsoon rains to nourish crops, the early onset of the dry season could mean a reduced harvest. According to the Production Estimates and Crop Assessment Division of the U.S. Department of Agriculture’s Foreign Agricultural Service, the lack of rain affected the tail end of the growing season, and while most crops should be fine, yields could be reduced because of a lack of rain. The government of Thailand has already announced that the rice harvest will be less than expected, and the AFP reports that the Cambodian government is concerned about potential food shortages. In Cambodia, 80-85 percent of all rice is grown during the monsoon season.
The early end to the rainy season could spell trouble for the next growing season, which depends on irrigation instead of rainfall. Not only did the rains end early, but less rain fell during the monsoon, and that could mean a shortage of irrigation water stored in reservoirs, particularly if the dry season lasts longer than normal.
The above image confirms the absence of clouds associated with precipitation over Southeastern Asia during the month of October. The image is based on measurements of outgoing longwave radiation (OLR), the amount of heat being reflected from the Earth back into space, in Watts per square meter. Clouds tend to be cold, while land masses are warmer. Outgoing longwave radiation can help scientists monitor rainfall by showing where rainfall clouds are, or in this case, where they aren’t. The above image is a comparison of the amount of outgoing longwave radiation observed in October 2004, to the October average observed from 1979 to 1995. Areas that radiated more heat than average are red and those that radiated less are blue. Southeast Asia was radiating more heat than normal in October—a sign that fewer cool clouds covered the region. Indonesia, northern Australia, and parts of China also appear to be warmer, and possibly drier, than normal. This image was derived from measurements made by the TIROS Operational Vertical Sounder (TOVS) onboard the NOAA-POES satellite series.
NASA image by Jesse Allen, Earth Observatory, using data analyzed by Assaf Anyamba and provided by NOAA’s National Center for Environmental Prediction.
posted to Earth News. at Thu Nov 11 23:55:54 -0500 2004.
Between the afternoon of November 2 and November 3, 2004, a layer of haze built up in east-central China near the coast of Bo-Hai (the body of water at right). The eastern coastal plain in this part of China is frequently plagued with poor air quality, due to increasing vehicle pollution in large cities like Beijing, coal-fired power plants, and home heating and cooking fires. The location and topography do not help the situation. The mountains to the west trap the haze over the plain, and the meteorological influences in the area often create what’s called a “temperature inversion,†in which the air near the surface is cooler than the air higher in the atmosphere. (Normally, air temperatures decrease with altitude.) Since cooler air has less tendency to rise, the haze can remained trapped near the surface until the weather changes.
The top image is from November 2nd, and was acquired in true-color by the Moderate Resolution Imaging Spectroradiometer (MODIS) instrument aboard NASA’s Aqua satellite. The lower image, from November 2nd and also acquired by the Aqua MODIS instrument, shows the same scene without the pollution. The pollution gathered overnight, and lingered until November 5th. By November 6th, a new cloud of haze had accumulated.
Image courtesy MODIS Land Rapid Response Team at NASA GSFC
posted to Earth News. at Wed Nov 10 23:52:16 -0500 2004.
Across the Deep South, numerous fires were detected by the Moderate Resolution Imaging Spectroradiometer (MODIS) on NASA’s Aqua satellite on November 9, 2004. The fires, marked in red, are spread across numerous states in the region, and may be seasonal agricultural burning. Late fall is the season for sugar cane burning in the area, when growers set fire to the cane fields to burn away the green leafy parts of the vegetation, allowing the sugar-containing stalk to be more easily harvested. The practice is cost-effective, but it does cause air pollution, and the Environmental Protection Agency is working with growers to develop burning practices that minimize exposure of downwind residents to harmful smoke.
At bottom left, waters in the Mississippi River Delta are nearly opaque, swirls of tan, dark brown, and green contrasting against the bluer waters farther out in the Gulf of Mexico.
NASA image courtesy the MODIS Rapid Response Team, NASA-Goddard Space Flight Center
posted to Earth News. at Wed Nov 10 22:20:52 -0500 2004.
Corrientes, Argentina (population 347,000), sits on the east bank of the Paran? River, South America?s third largest river (after the Negro and Amazon Rivers). From its headwaters in southeastern Brazil, the river flows southwestward around southern Paraguay, and then into Argentina. Corrientes is located just inside Argentina, across the river from the southwestern tip of Paraguay.
The bridge over the Paran?, built in the 1970s, connects Corrientes to its sister city, Resistencia, outside left margin) on the western bank of the river. Sun glint on the river gives it a silvery glow and emphasizes channel islands in the river, side channels, and meander scars on the floodplain opposite the city, and even reveals the pattern of disturbed flow downstream of the bridge pylons.
Although it lies 500 miles from the sea, Corrientes is a major port city. Barge traffic from Corrientes supplies landlocked Paraguay and Bolivia and interior parts of Brazil. Local manufactures and farm products are sent downstream to Buenos Aires, where the Paran? empties into the Atlantic Ocean through the Rio de la Plata Estuary. Founded in 1588, the city's name is an abbreviated version of the historic one, “San Juan de Vera de las Siete Corrientes†(San Juan de Vera of the Seven Currents), which honored the city’s founder and the complex behavior of the river in that location. The sun glint on the river highlights the different currents.
The old part of the city appears as a zone of smaller, more densely clustered city blocks along the river to the north of a major highway, which runs through Corrientes from the General Belgrano Bridge to the northeast (upper right of image). Larger blocks of the younger cityscape, with more green space, surround these core neighborhoods.
posted to Earth News. at Mon Nov 08 09:43:39 -0500 2004.
The Moderate Resolution Imaging Spectroradiometer (MODIS) on NASA’s Aqua and Terra satellites helped scientists identify this large algal bloom off the eastern coast of Tasmania. Large blooms have not been detected in the Tasman Sea in the past, and scientists from CSIRO Marine Research, the largest marine research organization in Australia, believe this one resulted from the natural upwelling of nutrients along the island’s coast. The bloom is made up of coccolithophores, and is not believed to be harmful to the coastal ecosystem.
MODIS imagery, such as the image above, revealed just how large this bloom is. The bloom forms bright blue-green clouds in the water that stretch from Flinders Island in the north down the entire east coast of Tasmania. The color is caused by light reflecting off the chalky outer scales of millions of microscopic coccoliths. The effect is a cloud of bright blue or green water in satellite imagery. In addition to helping scientists identify algal blooms, the MODIS images “provide a valuable interpretation for researchers wanting to understand any impact this species may have in the coastal or offshore environments,†said Dr Susan Blackburn, a CSIRO researcher, in a press release. The above MODIS image was acquired on October 20, 2004, by NASA’s Terra satellite.
NASA image created by Jesse Allen, Earth Observatory, using data obtained from the NASA Goddard Earth Sciences DAAC.
posted to Earth News. at Thu Oct 28 16:27:34 -0400 2004.
A series of powerful earthquakes over the weekend shook Niiagata Prefecture on Northwest Honshu, 260 km (160 miles) north of Tokyo. The first quake registered 6.5 on the Richter Scale, according to the National Earthquake Information Center, and occurred at 8:56 Universal Time, in the early evening local time as many residents were starting their dinners. At present, some 24 deaths have been attributed to the quake, or to the series of strong aftershocks, some above 6.0 in magnitude. Rescuers are still looking for missing people and, unfortunately, the death toll may climb further.
The quakes also injured approximately 2,000 people, stretching local hospitals to their limits. Electrical power has been cut off for some 300,000 residents. Many people remain in emergency shelters, fearful of returning to homes that may be unstable from the damage caused by the quakes.
Earthquakes are not uncommon in Japan, which rests on the Pacific “Rim of Fire,†where the North American plate (on which northern Honshu rests) grates up against the Eurasian Plate.
This visualization shows the topography of northwestern Japan around the initial epicenter. Color represents elevation and shading shows slope (illuminated from the lower left, as the area would appear at this time of year in the early morning). The land surface elevation data shown here were collected by NASA’s Shutte Radar Topograph Mission (SRTM) in February 2000. The locations and information about the quakes were obtained from the USGS National Earthquake Information Center.
NASA image created by Jesse Allen, Earth Observatory, using data obtained from the Global Land Cover Facility
posted to Earth News. at Tue Oct 26 00:08:22 -0400 2004.
The month that has passed since Tropical Storm Jeanne flooded Haiti has allowed time for a closer look at the tragic flooding. While the floods that killed over a thousand in Gonaives were initially easy to spot, this analysis shows how much more of the northwestern arm of the island was affected. The image compares synthetic aperture radar (SAR) data collected by the RADARSAT-1 satellite (Canadian Space Agency) on September 24 and 30 to data collected on July 16, 2003. The changes have been color-coded and superimposed on a Landsat-7 scene, taken on July 3, 2003.
Marbled veins of color across the entire region reveal extensive flooding. In the above image, areas that were dry on September 24, but flooded on September 30 as flood waters advanced and drained, are colored blue. Regions that were flooded between September 24 and September 30 are pink, and areas that were flooded on the 24th, but drained by the 30th are colored red. Landslides and regions that were covered with sediment after flash floods coursed through are green. Grey land shows where no changes were detected. Though grey seems to dominate the image, a close look shows that most of the northwestern peninsula was affected by the floods. Since the region was one of the primary crop areas in Haiti, the widespread flooding could have a lasting impact on the country.
Image and analysis courtesy ParBleu Technologies. Landsat image provided by the Global Land Cover Facility at the University of Maryland. RADARSAT-1 SAR data copyright the Canadian Space Agency and Radarsat International.
posted to Earth News. at Tue Oct 26 00:08:13 -0400 2004.
The mountain community of Alpine, Arizona (image center), can be found in the midst of the Apache-Sitgreaves National Forest. Situated at the eastern end of the White Mountains and near the headwaters of the San Francisco River, Alpine is the highest town in Arizona at an elevation of 8,050 feet. The town was settled in 1876. Just east of Alpine, close to the New Mexico border, Luna Lake is visible. The wetlands surrounding the lake house a wildlife refuge for bald and golden eagles.
This perspective image was created by joining Landsat 7 data and Digital Elevation Model (DEM) data. The Landsat 7 image was acquired on September 12, 2000 and combines ETM+ spectral bands 7, 4, and 2 as well as the panchromatic band.
NASA image created by Jesse Allen, Earth Observatory
posted to Earth News. at Sun Oct 24 11:42:56 -0400 2004.
Malta, an independent republic, consists of a small group of islandsMalta, Gozo, Kemmuna, Kemmunett, and Filflalocated in the Mediterranean Sea south of Sicily, with a total area of 316 square kilometers. The capital and leading port of the country is Valletta, which appears as a gray patch around the two deep inlets on Malta’s northern coastline. About 400,000 people live on this island nation. The islands of Malta consist of low-lying coralline limestone plateaus surrounded by impermeable clay slopes. The highest point is 239 meters above sea level.
The many ancient monuments and remains on Malta attest to the great age of its civilization. Remains from Stone Age and Bronze Age peoples have been found in subterranean burial chambers. The islands became a Phoenician colony about 1000 B.C. They were later occupied by the Greeks, who called the colony Melita, and later the islands passed successively into the possession of Carthage and Rome. The islands were occupied by Arabs in 870 A.D. A Norman army conquered the Maltese Arabs in 1090, and Malta was later made a feudal fief of the kingdom of Sicily. In 1530 Holy Roman Emperor Charles V granted Malta to the Knights of Saint John of Jerusalem, who ruled the islands until the 19th century. In 1798 Napoleon invaded and occupied the islands during his Egyptian campaign. Unwilling to be ruled by France, the Maltese appealed to Britain, and in 1799 British naval officer Horatio Nelson besieged Valletta and compelled the withdrawal of the French. In 1814 Malta became part of the British Empire as a crown colony.
This natural-color image was acquired on July 29, 2001, by the Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) aboard NASA’s Terra satellite.
Image courtesy NASA/GSFC/MITI/ERSDAC/JAROS, and U.S./Japan ASTER Science Team
posted to Earth News. at Sun Oct 24 11:42:25 -0400 2004.
A river of smoke more than 100 kilometers wide streams several hundred
kilometers southward from fires (marked in red) in northern China (top
left) in this image from the Moderate Resolution Imaging
Spectroradiometer (MODIS) on NASA’s Aqua satellite on
October 15, 2004. Another large cluster of fires is burning in
southeastern Russia (right).
According to news reports on October 18, at least some of the fires
in China were burning in and near forestry farms in Northeast China's
Heilongjiang Province, and thousands of people and their property were
threatened by the blazes. The cause of the fires was still unknown.
Across the Amur River (called Heilong Jiang in Chinese), a state of
emergency had been declared in southeastern Russia as fires raged in the
region’s taiga forests, steppes, and peat bogs. Strong winds were
fanning the rapidly spreading fires, and weather was not expected to
improve in the short term.
Image courtesy Jacques Descloitres, MODIS Land Rapid Response Team at NASA GSFC
posted to Earth News. at Mon Oct 18 23:45:51 -0400 2004.
The high peaks of the Andes form the backbone of South America and the political border between Chile and Argentina. Formed from the subduction of the Nazca Plate under the South American Plate, the south-central Andes also includes several major volcanoes. One of the most active border volcanoes is Volcan Maipo, located just southeast of Santiago, Chile. The volcano’s summit (5264m) rests in the large Diamante Caldera, and is defined by a radial drainage pattern highlighted by snow cover (center right of image). Lava flows from an 1826 eruption blocked drainage within the caldera, forming Lake Diamante. The lake is a popular tourist destination. Maipo’s last significant eruption was in 1908.
Imagery of the region from the International Space Station includes seasonal observations—this image shows the volcano near the southern hemisphere spring equinox. The lake, just east of Maipo’s peak, is still ice covered. However, the increasing temperatures of spring are suggested by a muddy-looking streak near the lower left corner. The streak appears to be a landslide or avalanche that flowed westward down a rugged slope, possibly triggered by instability in the snowpack due to snow melt.
Astronaut photograph ISS009-E-22625 was acquired September 14, 2004 with a Kodak 760C digital camera with a 180 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.
posted to Earth News. at Sun Oct 17 23:53:39 -0400 2004.
The combined smoke from the Freds and Power Fires in northern California southwest of Lake Tahoe was filling in the northern end of the Sacramento Valley on October 14, 2004. This image was captured by the Moderate Resolution Imaging Spectroradiometer (MODIS) on NASAs Aqua satellite in the afternoon, when smoke had become so thick the actively burning areas of the fire that MODIS on the Terra satellite detected during its morning overpass could no longer be picked up.
Southwest of Lake Tahoe, the northernmost band of thick smoke is associated with the Freds Fire, while the central and southern ones are associated with the Power Fire. The smoke has risen far enough into the air to be casting a shadow onto another, thinner layer of smoke below. Smoke nestles into the ravines and canyons of the many rivers that run off the Sierra Nevada Mountains, causing them to stand out from the forested terrain.
Other landmarks in the scene include San Francisco Bay, along the bottom edge to the left of center; Clear Lake, in the upper left quadrant; the southern end of Nevadas Pyramid Lake, at upper right; and the gray-colored rock of Yosemite National Park, to the west of Mono Lake at bottom right. A small fire was detected by MODIS in that area and is outlined in red.
NASA image courtesy the MODIS Rapid Response Team, NASA-Goddard Space Flight Center
posted to Earth News. at Fri Oct 15 22:08:23 -0400 2004.
IKONOS captured this spectacular view of the ongoing eruption of the Mount Belinda volcano on Montagu Island, in the South Sandwich Islands of the Scotia Sea, some 250 kilometers from South Georgia Island. The South Sandwich Islands are situated approximately between the southern tip of South America and mainland Antarctica. Montagu Island is dominated by the long-dormant Mount Belinda stratovolcano, which rises 1370 meters above sea level. This volcano is totally ice-covered, and until late 2001, it was inactive, thereby accumulating a thick cover of ice and snow. However, as this image shows, the volcano began erupting in late 2001, spewing basaltic lavas that have melted the ice, producing a marvelous natural laboratory for studying lava-ice interactions relevant to the biology of extreme environments as well as to processes believed to be important on the planet Mars.
This image was acquired on October 1, 2004, and shows the steaming vent crater and dark, basaltic tephra covered ice surfaces to the north of the lavas which erupted down the northern flank of the Mt. Belinda stratovolcano. The steam plume is drifting toward the north, and light clouds surround the south side of the crater. White chunks of ice float in the ocean surrounding Montagu Island.
The full resolution version of the image shown above has a resolution of 4 meters per pixel, but IKONOS also acquired the image at 1 meter per pixel (3.20 Mb). Thanks to the 1-meter imaging capabilities of the IKONOS satellite, dynamic processes such as those on remote, uninhabited islands, can be monitored from orbit, thereby serving to target more intensive field studies when they are justified. As such, IKONOS imaging of localities such as active eruptions involving ice-lava interactions, represents a new form of scientific exploration of planet Earth.
Image copyright Space Imaging , caption by Dr. Jim Garvin, NASA Chief Scientist for Mars and the Moon
posted to Earth News. at Thu Oct 14 23:17:34 -0400 2004.
Lake Teletskoye, one of Siberia’s prime tourist destinations, is a large lake that is nestled in a narrow valley between the snow-capped Al-tyntu (west, at top) and Korbu (east, at bottom) mountain ridges of the Altai Mountains. The lake is nearly 80 kilometers long by 5 kilometers wide and 325 meters deep; it is one of the deepest lakes in the world.
But Lake Teletskoye is more than a large, deep lake. It is located within the 9,000 km 2 Altaisky Zapovednik nature reserve, which helps protect its unspoiled waters. The main flow into the lake is the Tchulyshman River, but approximately 70 rivers and hundreds of seasonal streams also flow into the lake. The lake water drains and ultimately flows north to become one of Siberia’s great rivers, the Ob. Surrounding the lake are ancient taiga forests. Large lakes such as Teletskoye serve as repositories of regional paleoclimate data including sediment records and atmospheric pollutants. Teletskoye is included as one of Russia’s long-term ecological monitoring sites.
Astronaut photograph ISS008-E-7600 was acquired December 10, 2003 with a Kodak K-760C digital camera with a 155 mm lens and is provided by Earth Observations, Image Analysis Laboratory, 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.
posted to Earth News. at Mon Oct 11 22:11:51 -0400 2004.
If you followed the marine food chain to its last link, you would find phytoplankton. The microscopic marine plants that form the basis of ocean life depend on many variable factors to sustain their own existence. Like land-based plants, phytoplankton need sunlight and nutrients like iron, nitrate, and phosphate. The amount of phytoplankton that can grow in any section of ocean depends on the availability of these factors.
In the Arabian Sea, phytoplankton thrives in a narrow window of time defined by seasonal monsoons. During the summer monsoon, strong winds blow from the southwest across the Arabian Sea. These winds stir ocean currents, allowing cold, nutrient-rich water to rush up from the bottom. The winds also carry minerals from the land onto the surface of the ocean. The added nutrients from both sources feed the tiny ocean plants.
Though the summer monsoon provides nutrients to the plants, it also limits their growth by blocking sunlight. In June and July, thick, heavy clouds cover the ocean, lowering the amount of light that reaches the surface of the ocean. In August, the clouds typically clear, letting the life-giving light shine through. (To learn more, read "Illuminating Photosynthesis in the Arabian Sea." ) In October, the winds begin to reverse, and currents change so that fewer nutrients are available at the surface. It is in this August-to-October window when nutrients are still plentiful and sunlight is strong that phytoplankton grow most readily in the Arabian Sea.
This year is no exception. On October 6, 2004, the Sea-viewing Wide Field-of-view Sensor aboard the OrbView-2 satellite captured the above images showing high concentrations of phytoplankton in the Arabian Sea. The chlorophyll that the plants use to convert light to food tints the water green in the natural color image (top). The phytoplankton are growing in large swirls that follow the eddies and currents of the surface water. In the lower image, ocean chlorophyll concentrations are shown. Not surprisingly, concentrations appear to be highest near the coast where upwelling makes nutrients more available.
NASA images courtesy the SeaWiFS Project , NASA/Goddard Space Flight Center, and ORBIMAGE .
posted to Earth News. at Sat Oct 09 09:42:42 -0400 2004.
With sustained winds of 160 mph (257 kph) and gusts of up to 185 mph (298 kph), Super Typhoon Ma-On was situated due south of Japan on October 8, 2004. The eye of the storm was located about 621 miles (1,000 km) southwest of Tokyo and was moving north-northeastward at about 25 mph (40 kph). As the waters south of Japan are currently warmer than average, Ma-On may not weaken much as it approaches Japan, making it an extremely dangerous storm. Given its current trajectory, forecasts suggest that Super Typhoon Ma-On will make landfall somewhere between Kyoto and Tokyo within the next 48 hours. As Ma-On passes over mountains in the central part of the island, there will likely be extremely heavy precipitation in various places with the potential for flash flooding and mudslides. Local residents are encouraged to take safety precautions.
The U.S. Navys Joint Typhoon Warning Center is an excellent source of timely information about Typhoon Ma-On as it approaches land.
The true-color image above was acquired on October 8, 2004, by the Moderate Resolution Imaging Spectroradiometer (MODIS) aboard NASAs Aqua satellite. The high-resolution copy available above is 500 meters per pixel, but additional copies are also available.
NASA image courtesy Jeff Schmaltz, MODIS Rapid Response team, Goddard Space Flight Center
posted to Earth News. at Sat Oct 09 09:03:56 -0400 2004.
After more than a decade of inactivity, Mount St. Helens rumbled back to life in September 2004. An ongoing series of tremors within the volcano coupled with upward movement of magma toward its caldera prompted geologists to issue a Level 3 alert on October 2, stating that Mount St. Helens could experience a moderately severe eruption at any time.
In order to help geologists and vulcanologists assess the nature and magnitude of the risk, on September 24, 2004, NASA flew a low-altitude aircraft carrying the MODIS/ASTER Airborne Simulator (MASTER) directly over the volcano to obtain high-resolution images of its caldera. The images above show the caldera in spectacular detail; the high-resolution copies also available above have a spatial resolution of 3 meters per pixel. The top image shows Mount St. Helens in natural color while the bottom scene was produced using MASTERs thermal infrared detectors. The bulge in the center of the volcanos caldera is the lava dome, which has been growing in size in recent weeks due to the upward pressure of magma within the volcano. The red-orange patches show where heat is venting from the lava dome.
After these images were obtained, Mount St. Helens has emitted several plumes of ash and steam, as if to validate geologists warning that it could erupt at any time. However, on October 6, geologists lowered the volcano’s alert level and even though the threat of an eruption appears to be subsiding they cautioned that “episodic changes in level of unrest over periods of days to weeks, or even months, are possible.â€
NASA images courtesy Jeff Myers and Rose Dominguez, MASTER Project, Ames Research Center
posted to Earth News. at Thu Oct 07 06:01:42 -0400 2004.
Arctic sea ice has declined sharply over the last three years. For years, scientists at the University of Colorado at Boulder have been tracking the extent and thickness of sea ice across the Arctic Circle. Every September researchers produce a composite map of Arctic sea ice and compare that years measurements to the longer-term average. September is the end of the summer melt period and so measurements made during that month provide an important indicator of the state of Arctic ice cover. This year scientists found that ice extent in September 2004 was 13.4 percent less than average. They observed similar declines in September 2003, when ice cover was 12 percent less than average, and in September 2002, when ice cover was at its lowest extent ever observed—15 percent below average. That year, the loss in ice extent equaled an area roughly twice the size of Texas.
The false-colors in the maps above show the loss of sea ice cover in September for each of the last three years. The colors represent a value known as “sea ice concentration anomaly.†Derived from satellite-based Special Sensor Microwave/Imager (or SSM/I) data, the images show how the thickness of the ice compares to average Arctic ice conditions. Yellow and red hues show where the ice is thicker than average, while light and dark blue shades show thinner-than-average conditions. Teal represents little or no difference. Gray areas show where no data are available. (Note: anomalies are not calculated north of the circle centered around the North Pole because there are no satellite data for this region prior to 1988. Satellite measurements of Arctic sea ice began in November 1978.)
In their October 4, 2004, press release, University of Colorado scientists reported that the decline in Arctic Sea ice points to “acceleration of the downward trend.†They said one possible explanation for the continuing loss of sea ice in this region is that climate warming from human activities like the burning of fossil fuels is becoming more apparent. “Climate models are in general agreement that one of the strongest signals of greenhouse warming will be a loss of Arctic sea ice,†stated Mark Serreze, of the U.S. National Snow and Ice Data Center (NSIDC). “Some [models] indicate complete disappearance of the summer sea ice cover by 2070.â€
For more information, please see Arctic Sea Ice Decline Continues.
Images courtesy National Snow and Ice Data Center
posted to Earth News. at Thu Oct 07 05:21:42 -0400 2004.
A mild warming of the surface waters in the Central Equatorial Pacific Ocean over the past few months has lead some researchers to believe that weak to moderate El Niño conditions will develop during the fall of 2004. However, a warming of the waters adjacent to South America has yet to occur. There the trade winds continue to blow more strongly than normal making warming of the surface waters off the South American coast unlikely. Since the major 1997-98 El Niño event, the trade winds of the equatorial Pacific have exhibited a “split personality†mode in which the central Pacific warms while the eastern Pacific sea surface temperature remains cool. In the west, occasional weakening of the trade winds has occurred; however, in the east, the trades hold steady or have been stronger than normal. This situation does not allow a warm signal from the central Pacific to move eastward and warm the waters off South America as is more traditionally associated with El Niño.
This split-personality mode does not have the same effects on weather as does a typical El Niño, which is known to bring increased rainfall to Southern California while inhibiting U.S. east coast hurricanes from making landfall. NASA’s Seasonal-to-Interannual Prediction Project (or NSIPP) forecast models for the equatorial Pacific show no indication of a significant warming of the waters off of South America, nor a change in the trade winds. NASA continues to monitor the situation in the Pacific closely with its Earth Observing System (EOS) satellites, and will be alert to any change in the current split personality mode of the equatorial trade winds.
The false-color image above represents the NSIPP model’s prediction of sea surface temperature and soil moisture conditions on October 11, 2004 (one week after this image was published). The colors in the ocean represent “temperature anomalyâ€blue means up to 4°C colder than average and red means up to 4°C warmer than average. The colors on land represent soil moisture. Dark green shows where the soil contains more moisture than average due to increased rainfall and dark brown shows where the soil contains less moisture than average due to dry or drought conditions. The black lines with arrows show the predicted direction of the atmospheric circulation patterns.
Click to play the NSIPP forecast animation (10.1 MB), which shows predicted conditions from September 2004 through August 2005. It is interesting to note that while the NSIPP model doesn’t predict any significant El Niño conditions for this year, it does forecast the onset of an El Niño in the summer of 2005. However, NASA oceanographer and climate modeler David Adamec cautions us to take that forecast with a grain of skepticism—the accuracy of the NSIPP model is not very accurate more than 6 months into the future.
NASA image and animation courtesy David Adamec, NSIPP Project, Goddard Space Flight Center
posted to Earth News. at Thu Oct 07 05:21:09 -0400 2004.
Scientists from the University of Washington and the National Oceanic and Atmospheric Administration (NOAA) report that a toxic bloom of algae has appeared in the eastern Pacific, located about 24 km (15 miles) off the northwest coast of Washington. Situated in the region known as the Juan de Fuca eddy, the bloom spans a large area roughly 48 km (30 miles) across. Scientists report finding concentrations of pseudo-nitzschia as high as 11 million cells per liter of sea water. Such a bloom is considered unusually intense and potentially lethal for humans. Even 200 cells per liter is considered dangerous.
Pseudo-nitzschia can release domoic acid, which has been found to accumulate in the tissue of shellfish. If ingested by humans, domoic acid will attack tissue in the brain that humans use for memory and learning. There is some concern that if a major storm passes through it could push the bloom eastward into near-shore waters. Officials in Washington are closely monitoring the situation.
Harmful algal blooms have been reported with increasing numbers and intensity in recent years, typically forming just outside the Strait of Juan de Fuca. This strait links Puget Sound to the Pacific Ocean. Scientists believe this years bloom is being fed by nutrients upwelled from near the ocean bottom as well as nutrients swept off the land into the sea from Vancouver and Washington.
The true-color images above show the region affected on September 24 and 26, 2004. The scenes were acquired by the Sea-viewing Wide Field-of-view Sensor aboard the OrbView-2 satellite. Note the greenish swirls in the water, in contrast to its usual dark blue color. It is impossible to say, using satellite imagery alone, which of the bloom shown in these images is pseudo-nitzschia and which is harmless phytoplankton, but such imagery can help scientists monitor current patterns and see which way the bloom may spread over time.
NASA images courtesy the SeaWiFS Project, Goddard Space Flight Center, and ORBIMAGE
posted to Earth News. at Mon Oct 04 13:37:33 -0400 2004.
The Moon (or Luna) has occupied a prominent place in myth and folklore throughout human history. From mid-August to mid-October the Moon rises at almost the same time every evening in the northern mid-latitudes. The bright disk of Luna provides enough dependable light at this time of year to allow longer days for harvesting crops—which has lead to the “Harvest Moon†of numerous songs, stories, paintings and photographs. The Moon also inspired the most ambitious human endeavor to date—landing astronauts on its surface to examine our closest celestial neighbor directly. Where were you on July 16, 1969? If you were alive and sentient that day, you probably were glued to a television set somewhere on the planet—at home with your family, gazing avidly through a storefront window, or gathered with friends at a community center or vacation cottage.
America and much of the world watched, awestruck, as astronauts landed on the Moon and looked back at Earth. Together with astronaut Neil Armstrong, humanity indeed took a giant leap forward that day. Images taken by the Apollo astronauts helped humans break through their restrictive worldview to see the Earth as it wasa fragile water planet with a few land masses, floating in the void of space. In much the same way that the Harvest Moon illuminates our planet, reflected light from the Earth (“Earthshineâ€) illuminates the dark portion of the crescent Moon.
This image from Apollo 11 shows the Earth rising over the limb of the Moon much as the Harvest Moon does from our planetary perspective. While the Harvest Moon has helped humans alter their local ecosystems for agriculture, images such as this looking “back home†helped raise awareness of the Earth’s planetary ecosystem. The Apollo 11 images provided a global backdrop for the building U.S. environmental movement, including a surge of citizen-led environmental cleanups in the 1960s and 70s, and implementation of key national environmental policies.
Astronaut photograph AS11-44-6548 was acquired in July of 1969 with a Hasselblad film camera. The image is provided by the Earth Observations and Image Analysis Laboratory, 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.
posted to Earth News. at Mon Oct 04 05:55:33 -0400 2004.
A series of powerful earthquakes over the weekend shook Niiagata Prefecture on Northwest Honshu, 260 km (160 miles) north of Tokyo. The first quake registered 6.5 on the Richter Scale, according to the National Earthquake Information Center, and occurred at 8:56 Universal Time, in the early evening local time as many residents were starting their dinners. At present, some 24 deaths have been attributed to the quake, or to the series of strong aftershocks, some above 6.0 in magnitude. Rescuers are still looking for missing people and, unfortunately, the death toll may climb further.
The quakes also injured approximately 2,000 people, stretching local hospitals to their limits. Electrical power has been cut off for some 300,000 residents. Many people remain in emergency shelters, fearful of returning to homes that may be unstable from the damage caused by the quakes.
Earthquakes are not uncommon in Japan, which rests on the Pacific “Rim of Fire,†where the North American plate (on which northern Honshu rests) grates up against the Eurasian Plate.
This visualization shows the topography of northwestern Japan around the initial epicenter. Color represents elevation and shading shows slope (illuminated from the lower left, as the area would appear at this time of year in the early morning). The land surface elevation data shown here were collected by NASA’s Shutte Radar Topograph Mission (SRTM) in February 2000. The locations and information about the quakes were obtained from the USGS National Earthquake Information Center.
NASA image created by Jesse Allen, Earth Observatory, using data obtained from the Global Land Cover Facility
The mountain community of Alpine, Arizona (image center), can be found in the midst of the Apache-Sitgreaves National Forest. Situated at the eastern end of the White Mountains and near the headwaters of the San Francisco River, Alpine is the highest town in Arizona at an elevation of 8,050 feet. The town was settled in 1876. Just east of Alpine, close to the New Mexico border, Luna Lake is visible. The wetlands surrounding the lake house a wildlife refuge for bald and golden eagles.
This perspective image was created by joining Landsat 7 data and Digital Elevation Model (DEM) data. The Landsat 7 image was acquired on September 12, 2000 and combines ETM+ spectral bands 7, 4, and 2 as well as the panchromatic band.
NASA image created by Jesse Allen, Earth Observatory
Malta, an independent republic, consists of a small group of islandsMalta, Gozo, Kemmuna, Kemmunett, and Filflalocated in the Mediterranean Sea south of Sicily, with a total area of 316 square kilometers. The capital and leading port of the country is Valletta, which appears as a gray patch around the two deep inlets on Malta’s northern coastline. About 400,000 people live on this island nation. The islands of Malta consist of low-lying coralline limestone plateaus surrounded by impermeable clay slopes. The highest point is 239 meters above sea level.
The many ancient monuments and remains on Malta attest to the great age of its civilization. Remains from Stone Age and Bronze Age peoples have been found in subterranean burial chambers. The islands became a Phoenician colony about 1000 B.C. They were later occupied by the Greeks, who called the colony Melita, and later the islands passed successively into the possession of Carthage and Rome. The islands were occupied by Arabs in 870 A.D. A Norman army conquered the Maltese Arabs in 1090, and Malta was later made a feudal fief of the kingdom of Sicily. In 1530 Holy Roman Emperor Charles V granted Malta to the Knights of Saint John of Jerusalem, who ruled the islands until the 19th century. In 1798 Napoleon invaded and occupied the islands during his Egyptian campaign. Unwilling to be ruled by France, the Maltese appealed to Britain, and in 1799 British naval officer Horatio Nelson besieged Valletta and compelled the withdrawal of the French. In 1814 Malta became part of the British Empire as a crown colony.
This natural-color image was acquired on July 29, 2001, by the Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) aboard NASA’s Terra satellite.
Image courtesy NASA/GSFC/MITI/ERSDAC/JAROS, and U.S./Japan ASTER Science Team
A river of smoke more than 100 kilometers wide streams several hundred kilometers southward from fires (marked in red) in northern China (top left) in this image from the Moderate Resolution Imaging Spectroradiometer (MODIS) on NASA’s Aqua satellite on October 15, 2004. Another large cluster of fires is burning in southeastern Russia (right).
According to news reports on October 18, at least some of the fires in China were burning in and near forestry farms in Northeast China's Heilongjiang Province, and thousands of people and their property were threatened by the blazes. The cause of the fires was still unknown. Across the Amur River (called Heilong Jiang in Chinese), a state of emergency had been declared in southeastern Russia as fires raged in the region’s taiga forests, steppes, and peat bogs. Strong winds were fanning the rapidly spreading fires, and weather was not expected to improve in the short term.
Image courtesy Jacques Descloitres, MODIS Land Rapid Response Team at NASA GSFC
The high peaks of the Andes form the backbone of South America and the political border between Chile and Argentina. Formed from the subduction of the Nazca Plate under the South American Plate, the south-central Andes also includes several major volcanoes. One of the most active border volcanoes is Volcan Maipo, located just southeast of Santiago, Chile. The volcano’s summit (5264m) rests in the large Diamante Caldera, and is defined by a radial drainage pattern highlighted by snow cover (center right of image). Lava flows from an 1826 eruption blocked drainage within the caldera, forming Lake Diamante. The lake is a popular tourist destination. Maipo’s last significant eruption was in 1908.
Imagery of the region from the International Space Station includes seasonal observations—this image shows the volcano near the southern hemisphere spring equinox. The lake, just east of Maipo’s peak, is still ice covered. However, the increasing temperatures of spring are suggested by a muddy-looking streak near the lower left corner. The streak appears to be a landslide or avalanche that flowed westward down a rugged slope, possibly triggered by instability in the snowpack due to snow melt.
Astronaut photograph ISS009-E-22625 was acquired September 14, 2004 with a Kodak 760C digital camera with a 180 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.
The combined smoke from the Freds and Power Fires in northern California southwest of Lake Tahoe was filling in the northern end of the Sacramento Valley on October 14, 2004. This image was captured by the Moderate Resolution Imaging Spectroradiometer (MODIS) on NASAs Aqua satellite in the afternoon, when smoke had become so thick the actively burning areas of the fire that MODIS on the Terra satellite detected during its morning overpass could no longer be picked up.
Southwest of Lake Tahoe, the northernmost band of thick smoke is associated with the Freds Fire, while the central and southern ones are associated with the Power Fire. The smoke has risen far enough into the air to be casting a shadow onto another, thinner layer of smoke below. Smoke nestles into the ravines and canyons of the many rivers that run off the Sierra Nevada Mountains, causing them to stand out from the forested terrain.
Other landmarks in the scene include San Francisco Bay, along the bottom edge to the left of center; Clear Lake, in the upper left quadrant; the southern end of Nevadas Pyramid Lake, at upper right; and the gray-colored rock of Yosemite National Park, to the west of Mono Lake at bottom right. A small fire was detected by MODIS in that area and is outlined in red.
NASA image courtesy the MODIS Rapid Response Team, NASA-Goddard Space Flight Center
IKONOS captured this spectacular view of the ongoing eruption of the Mount Belinda volcano on Montagu Island, in the South Sandwich Islands of the Scotia Sea, some 250 kilometers from South Georgia Island. The South Sandwich Islands are situated approximately between the southern tip of South America and mainland Antarctica. Montagu Island is dominated by the long-dormant Mount Belinda stratovolcano, which rises 1370 meters above sea level. This volcano is totally ice-covered, and until late 2001, it was inactive, thereby accumulating a thick cover of ice and snow. However, as this image shows, the volcano began erupting in late 2001, spewing basaltic lavas that have melted the ice, producing a marvelous natural laboratory for studying lava-ice interactions relevant to the biology of extreme environments as well as to processes believed to be important on the planet Mars.
This image was acquired on October 1, 2004, and shows the steaming vent crater and dark, basaltic tephra covered ice surfaces to the north of the lavas which erupted down the northern flank of the Mt. Belinda stratovolcano. The steam plume is drifting toward the north, and light clouds surround the south side of the crater. White chunks of ice float in the ocean surrounding Montagu Island.
The full resolution version of the image shown above has a resolution of 4 meters per pixel, but IKONOS also acquired the image at 1 meter per pixel (3.20 Mb). Thanks to the 1-meter imaging capabilities of the IKONOS satellite, dynamic processes such as those on remote, uninhabited islands, can be monitored from orbit, thereby serving to target more intensive field studies when they are justified. As such, IKONOS imaging of localities such as active eruptions involving ice-lava interactions, represents a new form of scientific exploration of planet Earth.
Image copyright Space Imaging , caption by Dr. Jim Garvin, NASA Chief Scientist for Mars and the Moon
Lake Teletskoye, one of Siberia’s prime tourist destinations, is a large lake that is nestled in a narrow valley between the snow-capped Al-tyntu (west, at top) and Korbu (east, at bottom) mountain ridges of the Altai Mountains. The lake is nearly 80 kilometers long by 5 kilometers wide and 325 meters deep; it is one of the deepest lakes in the world.
But Lake Teletskoye is more than a large, deep lake. It is located within the 9,000 km 2 Altaisky Zapovednik nature reserve, which helps protect its unspoiled waters. The main flow into the lake is the Tchulyshman River, but approximately 70 rivers and hundreds of seasonal streams also flow into the lake. The lake water drains and ultimately flows north to become one of Siberia’s great rivers, the Ob. Surrounding the lake are ancient taiga forests. Large lakes such as Teletskoye serve as repositories of regional paleoclimate data including sediment records and atmospheric pollutants. Teletskoye is included as one of Russia’s long-term ecological monitoring sites.
Astronaut photograph ISS008-E-7600 was acquired December 10, 2003 with a Kodak K-760C digital camera with a 155 mm lens and is provided by Earth Observations, Image Analysis Laboratory, 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.
In the Arabian Sea, phytoplankton thrives in a narrow window of time defined by seasonal monsoons. During the summer monsoon, strong winds blow from the southwest across the Arabian Sea. These winds stir ocean currents, allowing cold, nutrient-rich water to rush up from the bottom. The winds also carry minerals from the land onto the surface of the ocean. The added nutrients from both sources feed the tiny ocean plants.
Though the summer monsoon provides nutrients to the plants, it also limits their growth by blocking sunlight. In June and July, thick, heavy clouds cover the ocean, lowering the amount of light that reaches the surface of the ocean. In August, the clouds typically clear, letting the life-giving light shine through. (To learn more, read "Illuminating Photosynthesis in the Arabian Sea." ) In October, the winds begin to reverse, and currents change so that fewer nutrients are available at the surface. It is in this August-to-October window when nutrients are still plentiful and sunlight is strong that phytoplankton grow most readily in the Arabian Sea.
This year is no exception. On October 6, 2004, the Sea-viewing Wide Field-of-view Sensor aboard the OrbView-2 satellite captured the above images showing high concentrations of phytoplankton in the Arabian Sea. The chlorophyll that the plants use to convert light to food tints the water green in the natural color image (top). The phytoplankton are growing in large swirls that follow the eddies and currents of the surface water. In the lower image, ocean chlorophyll concentrations are shown. Not surprisingly, concentrations appear to be highest near the coast where upwelling makes nutrients more available.
NASA images courtesy the SeaWiFS Project , NASA/Goddard Space Flight Center, and ORBIMAGE .
With sustained winds of 160 mph (257 kph) and gusts of up to 185 mph (298 kph), Super Typhoon Ma-On was situated due south of Japan on October 8, 2004. The eye of the storm was located about 621 miles (1,000 km) southwest of Tokyo and was moving north-northeastward at about 25 mph (40 kph). As the waters south of Japan are currently warmer than average, Ma-On may not weaken much as it approaches Japan, making it an extremely dangerous storm. Given its current trajectory, forecasts suggest that Super Typhoon Ma-On will make landfall somewhere between Kyoto and Tokyo within the next 48 hours. As Ma-On passes over mountains in the central part of the island, there will likely be extremely heavy precipitation in various places with the potential for flash flooding and mudslides. Local residents are encouraged to take safety precautions.
The U.S. Navys Joint Typhoon Warning Center is an excellent source of timely information about Typhoon Ma-On as it approaches land.
The true-color image above was acquired on October 8, 2004, by the Moderate Resolution Imaging Spectroradiometer (MODIS) aboard NASAs Aqua satellite. The high-resolution copy available above is 500 meters per pixel, but additional copies are also available.
NASA image courtesy Jeff Schmaltz, MODIS Rapid Response team, Goddard Space Flight Center
Arctic sea ice has declined sharply over the last three years. For years, scientists at the University of Colorado at Boulder have been tracking the extent and thickness of sea ice across the Arctic Circle. Every September researchers produce a composite map of Arctic sea ice and compare that years measurements to the longer-term average. September is the end of the summer melt period and so measurements made during that month provide an important indicator of the state of Arctic ice cover. This year scientists found that ice extent in September 2004 was 13.4 percent less than average. They observed similar declines in September 2003, when ice cover was 12 percent less than average, and in September 2002, when ice cover was at its lowest extent ever observed—15 percent below average. That year, the loss in ice extent equaled an area roughly twice the size of Texas.
The false-colors in the maps above show the loss of sea ice cover in September for each of the last three years. The colors represent a value known as “sea ice concentration anomaly.†Derived from satellite-based Special Sensor Microwave/Imager (or SSM/I) data, the images show how the thickness of the ice compares to average Arctic ice conditions. Yellow and red hues show where the ice is thicker than average, while light and dark blue shades show thinner-than-average conditions. Teal represents little or no difference. Gray areas show where no data are available. (Note: anomalies are not calculated north of the circle centered around the North Pole because there are no satellite data for this region prior to 1988. Satellite measurements of Arctic sea ice began in November 1978.)
In their October 4, 2004, press release, University of Colorado scientists reported that the decline in Arctic Sea ice points to “acceleration of the downward trend.†They said one possible explanation for the continuing loss of sea ice in this region is that climate warming from human activities like the burning of fossil fuels is becoming more apparent. “Climate models are in general agreement that one of the strongest signals of greenhouse warming will be a loss of Arctic sea ice,†stated Mark Serreze, of the U.S. National Snow and Ice Data Center (NSIDC). “Some [models] indicate complete disappearance of the summer sea ice cover by 2070.â€
For more information, please see Arctic Sea Ice Decline Continues.
Images courtesy National Snow and Ice Data Center
animations:
A mild warming of the surface waters in the Central Equatorial Pacific Ocean over the past few months has lead some researchers to believe that weak to moderate El Niño conditions will develop during the fall of 2004. However, a warming of the waters adjacent to South America has yet to occur. There the trade winds continue to blow more strongly than normal making warming of the surface waters off the South American coast unlikely. Since the major 1997-98 El Niño event, the trade winds of the equatorial Pacific have exhibited a “split personality†mode in which the central Pacific warms while the eastern Pacific sea surface temperature remains cool. In the west, occasional weakening of the trade winds has occurred; however, in the east, the trades hold steady or have been stronger than normal. This situation does not allow a warm signal from the central Pacific to move eastward and warm the waters off South America as is more traditionally associated with El Niño.
This split-personality mode does not have the same effects on weather as does a typical El Niño, which is known to bring increased rainfall to Southern California while inhibiting U.S. east coast hurricanes from making landfall. NASA’s Seasonal-to-Interannual Prediction Project (or NSIPP) forecast models for the equatorial Pacific show no indication of a significant warming of the waters off of South America, nor a change in the trade winds. NASA continues to monitor the situation in the Pacific closely with its Earth Observing System (EOS) satellites, and will be alert to any change in the current split personality mode of the equatorial trade winds.
The false-color image above represents the NSIPP model’s prediction of sea surface temperature and soil moisture conditions on October 11, 2004 (one week after this image was published). The colors in the ocean represent “temperature anomalyâ€blue means up to 4°C colder than average and red means up to 4°C warmer than average. The colors on land represent soil moisture. Dark green shows where the soil contains more moisture than average due to increased rainfall and dark brown shows where the soil contains less moisture than average due to dry or drought conditions. The black lines with arrows show the predicted direction of the atmospheric circulation patterns.
Click to play the NSIPP forecast animation (10.1 MB), which shows predicted conditions from September 2004 through August 2005. It is interesting to note that while the NSIPP model doesn’t predict any significant El Niño conditions for this year, it does forecast the onset of an El Niño in the summer of 2005. However, NASA oceanographer and climate modeler David Adamec cautions us to take that forecast with a grain of skepticism—the accuracy of the NSIPP model is not very accurate more than 6 months into the future.
NASA image and animation courtesy David Adamec, NSIPP Project, Goddard Space Flight Center
Pseudo-nitzschia can release domoic acid, which has been found to accumulate in the tissue of shellfish. If ingested by humans, domoic acid will attack tissue in the brain that humans use for memory and learning. There is some concern that if a major storm passes through it could push the bloom eastward into near-shore waters. Officials in Washington are closely monitoring the situation.
Harmful algal blooms have been reported with increasing numbers and intensity in recent years, typically forming just outside the Strait of Juan de Fuca. This strait links Puget Sound to the Pacific Ocean. Scientists believe this years bloom is being fed by nutrients upwelled from near the ocean bottom as well as nutrients swept off the land into the sea from Vancouver and Washington.
The true-color images above show the region affected on September 24 and 26, 2004. The scenes were acquired by the Sea-viewing Wide Field-of-view Sensor aboard the OrbView-2 satellite. Note the greenish swirls in the water, in contrast to its usual dark blue color. It is impossible to say, using satellite imagery alone, which of the bloom shown in these images is pseudo-nitzschia and which is harmless phytoplankton, but such imagery can help scientists monitor current patterns and see which way the bloom may spread over time.
NASA images courtesy the SeaWiFS Project, Goddard Space Flight Center, and ORBIMAGE
The Moon (or Luna) has occupied a prominent place in myth and folklore throughout human history. From mid-August to mid-October the Moon rises at almost the same time every evening in the northern mid-latitudes. The bright disk of Luna provides enough dependable light at this time of year to allow longer days for harvesting crops—which has lead to the “Harvest Moon†of numerous songs, stories, paintings and photographs. The Moon also inspired the most ambitious human endeavor to date—landing astronauts on its surface to examine our closest celestial neighbor directly. Where were you on July 16, 1969? If you were alive and sentient that day, you probably were glued to a television set somewhere on the planet—at home with your family, gazing avidly through a storefront window, or gathered with friends at a community center or vacation cottage.
America and much of the world watched, awestruck, as astronauts landed on the Moon and looked back at Earth. Together with astronaut Neil Armstrong, humanity indeed took a giant leap forward that day. Images taken by the Apollo astronauts helped humans break through their restrictive worldview to see the Earth as it wasa fragile water planet with a few land masses, floating in the void of space. In much the same way that the Harvest Moon illuminates our planet, reflected light from the Earth (“Earthshineâ€) illuminates the dark portion of the crescent Moon.
This image from Apollo 11 shows the Earth rising over the limb of the Moon much as the Harvest Moon does from our planetary perspective. While the Harvest Moon has helped humans alter their local ecosystems for agriculture, images such as this looking “back home†helped raise awareness of the Earth’s planetary ecosystem. The Apollo 11 images provided a global backdrop for the building U.S. environmental movement, including a surge of citizen-led environmental cleanups in the 1960s and 70s, and implementation of key national environmental policies.
Astronaut photograph AS11-44-6548 was acquired in July of 1969 with a Hasselblad film camera. The image is provided by the Earth Observations and Image Analysis Laboratory, 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.