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Tropical Cyclone Favio
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Tropical Cyclone Favio |
| Description |
Cyclone Favio was closing the gap between Madagascar and mainland Africa on February 21, 2007, preparing to strike Mozambique in coming days. The Joint Typhoon Warning Center forecast issued at 12:00 UTC (2:00 p.m. Mozambique local time) on February 21 indicated that Favio had sustained wind speeds of 100 knots (about 185 kilometers/hour, 115 miles/hour), with gusts up to 125 knots (about 232 kilometers/hour, 144 miles/hour), which made it a Category 3 storm. The forecast called for the storm to weaken before making landfall within 24 hours, but the impacts were still expected to be severe. The country was already water-logged from heavy rains associated with the onset of the monsoon, and severe flooding along the Zambezi River [ http://earthobservatory.nasa.gov/NaturalHazards/natural_hazards_v2.php3?img_id=14115 ] in mid-February killed dozens of people and forced more than a hundred thousand people to evacuate, according to reports [ http://www.reliefweb.int/rw/RWB.NSF/db900SID/LSGZ-6YMDSC?OpenDocument ] from the International Federation of Red Cross and Red Crescent Societies posted online by ReliefWeb. [ http://www.reliefweb.int/rw/dbc.nsf/doc100?OpenForm ] This data visualization shows Cyclone Favio in the middle of the Mozambique Channel between the island of Madagascar and Africa. The data were obtained by NASA's QuikSCAT [ http://winds.jpl.nasa.gov/missions/quikscat/index.cfm ], satellite on February 21, 2007, at 6:38 a.m. local time (3:38 UTC). The image depicts wind speed in color and wind direction with small barbs. White barbs point to areas of heavy rain. Favio appears as a well-formed spiral of winds centered around a strong eye where winds were calmer. This pattern is typical of tropical cyclones. Since the storm is in the Southern Hemisphere, the Coriolos force, which gives all hurricanes and cyclones their spin, turns the storm clockwise, the opposite direction to hurricanes and typhoons which form in the Northern Hemisphere. Measurements of the actual wind strength of cyclones are often higher than those measured by QuikSCAT. QuikSCAT employs a scatterometer, which sends pulses of microwave energy through the atmosphere to the ocean surface, and measures the energy that bounces back from the wind-roughened surface. The energy of the microwave pulses changes depending on wind speed and direction, giving scientists a way to monitor wind around the world. This technique does not work over land, but allows measurements in storms over oceans. Tropical cyclones, however, are difficult to measure. To relate the radar energy returned to the sensor to actual wind speed, scientists compare measurements taken from buoys and other ground stations to data the satellite acquired at the same time and place. Because the high wind speeds generated by cyclones are rare, scientists do not have corresponding ground information to know how to translate data from the satellite for wind speeds above 50 knots (about 93 km/hr or 58 mph). Also, the unusually heavy rain found in a cyclone distorts the microwave pulses in a number of ways, making a conversion to accurate wind speed difficult. Instead, the scatterometer provides a nice picture of the relative wind speeds within the storm and shows wind direction. NASA image courtesy of David Long, Brigham Young University, on the QuikSCAT Science Team [ http://winds.jpl.nasa.gov/ ], and the Jet Propulsion Laboratory. |
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Tropical Cyclone Favio
| Title |
Tropical Cyclone Favio |
| Description |
Tropical Cyclone Favio formed in the western Indian Ocean about 1,200 kilometers from Madagascar on February 14, 2007. It gradually moved southwest, passing well offshore of Reunion and Mauritius Islands. By February 20, it was just off the southern shore of Madagascar as a well-formed, mature storm. While the storm system had largely skirted around populated areas to that point, forecasters were concerned about its behavior as it entered the warmer waters of the Mozambique Channel. The storm was forecast to reach Category Four [ http://www.nhc.noaa.gov/aboutsshs.shtml ] strength before coming ashore and tracking inland through Zimbabwe and Zambia, bringing heavy rains to already flooded areas. [ http://earthobservatory.nasa.gov/NaturalHazards/natural_hazards_v2.php3?img_id=14115 ] This photo-like image was acquired by the Moderate Resolution Imaging Spectroradiometer (MODIS) [ http://modis.gsfc.nasa.gov/ ] on the Aqua [ http://aqua.nasa.gov/ ] satellite on February 20, 2007, at 2:15 p.m. local time (11:15 UTC). The storm was turning north around the southern end of Madagscar, headed for the Mozambique Channel. Favio had the recognizable shape of a southern-hemisphere tropical cyclone, with spiral arms showing its clockwise rotation. The spiral arms are well-defined and tightly wound. A distinct eye at the center of the storm is only partially filled with clouds (a "partially closed" eye). These are all signs of a well-developed and powerful storm, consistent with the cyclone's strength. According to the University of Hawaii's Tropical Storm Information Center, [ http:/NaturalHazards/natural_hazards_v2.php3 www.solar.ifa.hawaii.edu/Tropical/ ] Favio had steady winds of around 160 kilometers per hour (100 miles per hour) around the time MODIS made this observation. The high-resolution image provided above is at MODIS' full spatial resolution (level of detail) of 250 meters per pixel. The MODIS Rapid Response System provides this image at additional resolutions. You can also download a 250-meter-resolution Cyclone Favio KMZ file [ http://earthobservatory.nasa.gov/NaturalHazards/Archive/Feb2007/Favio.A2007051.1115.250m.kmz ] for use with Google Earth. [ http://earth.google.com/download-earth.html ] NASA image by Jeff Schmaltz, MODIS Rapid Response Team, [ http://rapidfire.sci.gsfc.nasa.gov ] Goddard Space Flight Center. |
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Tropical Cyclone Favio
| Title |
Tropical Cyclone Favio |
| Description |
Category 4-strength Cyclone Favio was closing the gap between Madagascar and mainland Africa on February 21, 2007, preparing to strike Mozambique in coming days. This image from the Moderate Resolution Imaging Spectroradiometer (MODIS) [ http://modis.gsfc.nasa.gov ] on NASA's Terra [ http://terra.nasa.gov ] satellite shows Favio stretched across the Mozambique Channel at 9:35 a.m. (local time) Wednesday morning. The outermost bands of clouds on the western side of the storm were already brushing the coast of Inhambane province in southern Mozambique. A thick ring of "boiling" clouds surrounds the eye of the storm. Favio had weakened slightly to a Category 3 storm between the time the image was acquired and this posting. The Joint Typhoon Warning Center forecast issued at 12:00 UTC (2:00 p.m. Mozambique local time) on February 21 indicated that Favio had sustained wind speeds of 100 knots (about 185 kilometers/hour, 115 miles/hour), with gusts up to 125 knots (about 232 kilometers/hour, 144 miles/hour). The forecast called for the storm to weaken before making landfall within 24 hours, but the impacts were still expected to be severe. The country was already water-logged from heavy rains associated with the onset of the monsoon, and severe flooding along the Zambezi River [ http://earthobservatory.nasa.gov/NaturalHazards/natural_hazards_v2.php3?img_id=14115 ] in mid-February killed dozens of people and forced more than a hundred thousand people to evacuate, according to reports [ http://www.reliefweb.int/rw/RWB.NSF/db900SID/LSGZ-6YMDSC?OpenDocument ] from the International Federation of Red Cross and Red Crescent Societies posted online by ReliefWeb. [ http://www.reliefweb.int/rw/dbc.nsf/doc100?OpenForm ] The high-resolution image provided above is at MODIS' full spatial resolution (level of detail) of 250 meters per pixel. The MODIS Rapid Response System provides this image at additional resolutions. You can also download a 250-meter-resolution Cyclone Favio KMZ file [ http://earthobservatory.nasa.gov/NaturalHazards/Archive/Feb2007/Favio.A2007052.0735.250m.kmz ] for use with Google Earth. [ http://earth.google.com/download-earth.html ] NASA image by Jeff Schmaltz, MODIS Rapid Response Team, [ http://rapidfire.sci.gsfc.nasa.gov ] Goddard Space Flight Center. |
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Tropical Cyclone Favio
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Tropical Cyclone Favio |
| Description |
) satellite on February 20 and February 22, 2007. TRMM was placed into its low-earth orbit in November 1997 to measure rainfall from space, however, it has also served as a valuable platform for monitoring tropical cyclones, especially over remote parts of the open ocean. The images show the rainfall intensity. Rain rates in the center of the swath are from the TRMM Precipitation Radar, while those in the outer portion are from the TRMM Microwave Imager. The rain rates are overlaid on infrared data from the TRMM Visible Infrared Scanner. TRMM shows that Favio was a well-organized storm on February 20 (top) with a central eye (dark blue area in the center) surrounded by an eyewall containing heavy rainfall (dark red areas). The storm is also very symmetric with good "banding" in the rain field, demonstrated by the tightly curved bands of moderate rain (green areas) spiraling in towards the center. These features are the hallmarks of a mature, intense tropical cyclone. Though the cyclone did not strike Madagascar, the red areas indicate that it dumped heavy rains on the southern tip of the island. As Favio crossed the Mozambique Channel it reached a peak intensity of 232 kilometers per hour (144 miles per hour, or 125 knots) on the early morning of February 22, making it a Category 4 storm. The cyclone then weakened slightly before slamming into southern Mozambique with sustained winds estimated at 204 km/hr (127 mph, 110 knots). TRMM took the lower image on February 22 soon after Favio made landfall in Mozambique. The image shows that although the eye was not as well defined as in the earlier image, the circulation is still robust, the spiral rainbands (green arcs) are still well defined. Maximum sustained winds were still estimated to be 167 km/hr (114 mph, 90 knots) at the time of this image but quickly diminished thereafter. The bands of heavy rain shown in this image triggered floods [ http://earthobservatory.nasa.gov/NaturalHazards/natural_hazards_v2.php3?img_id=14146 ] along rivers in Central Mozambique. Unfortunately for Mozambique, the storm-induced floods follow additional serious flooding on the Zambezi River [ http://earthobservatory.nasa.gov/NaturalHazards/natural_hazards_v2.php3?img_id=14125 ] to the north. TRMM is a joint mission between NASA and the Japanese space agency, JAXA. Images produced by Hal Pierce (SSAI/NASA GSFC) and caption by Steve Lang (SSAI/NASA GSFC)., These images track Cyclone Favio as it brushed the southern tip of the island of Madagascar, and then continued on to Mozambique. The storm came ashore over southern Mozambique on February 22, 2007, as a strong Category 3 storm. As of February 28, news reports had attributed four fatalities to the storm in Vilanculos, a coastal tourist town where the storm made landfall. Favio began as a tropical disturbance on February 11, 2007, in the central Indian Ocean south of Diego Garcia in the Chagos Archipelago. Slow to intensify, the system finally became a tropical storm three days later on February 14. Favio remained a tropical storm for the next several days as it made its way through the west-central Indian Ocean east of Mauritius, and finally began to intensify as it neared Madagascar. It became a Category 1 cyclone on February 19. As it rounded the southern tip of Madagascar, Favio continued to intensify and reached Category 3 intensity on February 20. The cyclone then took a more northwesterly path as it entered the Mozambique Channel. These images of the storm were taken by the Tropical Rainfall Measuring Mission (TRMM [ http://trmm.gsfc.nasa.gov/ ] |
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Tropical Cyclone Favio
| Title |
Tropical Cyclone Favio |
| Description |
) satellite on February 20 and February 22, 2007. TRMM was placed into its low-earth orbit in November 1997 to measure rainfall from space, however, it has also served as a valuable platform for monitoring tropical cyclones, especially over remote parts of the open ocean. The images show the rainfall intensity. Rain rates in the center of the swath are from the TRMM Precipitation Radar, while those in the outer portion are from the TRMM Microwave Imager. The rain rates are overlaid on infrared data from the TRMM Visible Infrared Scanner. TRMM shows that Favio was a well-organized storm on February 20 (top) with a central eye (dark blue area in the center) surrounded by an eyewall containing heavy rainfall (dark red areas). The storm is also very symmetric with good "banding" in the rain field, demonstrated by the tightly curved bands of moderate rain (green areas) spiraling in towards the center. These features are the hallmarks of a mature, intense tropical cyclone. Though the cyclone did not strike Madagascar, the red areas indicate that it dumped heavy rains on the southern tip of the island. As Favio crossed the Mozambique Channel it reached a peak intensity of 232 kilometers per hour (144 miles per hour, or 125 knots) on the early morning of February 22, making it a Category 4 storm. The cyclone then weakened slightly before slamming into southern Mozambique with sustained winds estimated at 204 km/hr (127 mph, 110 knots). TRMM took the lower image on February 22 soon after Favio made landfall in Mozambique. The image shows that although the eye was not as well defined as in the earlier image, the circulation is still robust, the spiral rainbands (green arcs) are still well defined. Maximum sustained winds were still estimated to be 167 km/hr (114 mph, 90 knots) at the time of this image but quickly diminished thereafter. The bands of heavy rain shown in this image triggered floods [ http://earthobservatory.nasa.gov/NaturalHazards/natural_hazards_v2.php3?img_id=14146 ] along rivers in Central Mozambique. Unfortunately for Mozambique, the storm-induced floods follow additional serious flooding on the Zambezi River [ http://earthobservatory.nasa.gov/NaturalHazards/natural_hazards_v2.php3?img_id=14125 ] to the north. TRMM is a joint mission between NASA and the Japanese space agency, JAXA. Images produced by Hal Pierce (SSAI/NASA GSFC) and caption by Steve Lang (SSAI/NASA GSFC)., These images track Cyclone Favio as it brushed the southern tip of the island of Madagascar, and then continued on to Mozambique. The storm came ashore over southern Mozambique on February 22, 2007, as a strong Category 3 storm. As of February 28, news reports had attributed four fatalities to the storm in Vilanculos, a coastal tourist town where the storm made landfall. Favio began as a tropical disturbance on February 11, 2007, in the central Indian Ocean south of Diego Garcia in the Chagos Archipelago. Slow to intensify, the system finally became a tropical storm three days later on February 14. Favio remained a tropical storm for the next several days as it made its way through the west-central Indian Ocean east of Mauritius, and finally began to intensify as it neared Madagascar. It became a Category 1 cyclone on February 19. As it rounded the southern tip of Madagascar, Favio continued to intensify and reached Category 3 intensity on February 20. The cyclone then took a more northwesterly path as it entered the Mozambique Channel. These images of the storm were taken by the Tropical Rainfall Measuring Mission (TRMM [ http://trmm.gsfc.nasa.gov/ ] |
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Tropical Cyclone Gamede
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Tropical Cyclone Gamede |
| Description |
Tropical Cyclone Gamede was in the western Indian Ocean off the shore of Madagascar on February 26, 2007. This powerful storm had been moving southward parallel to the eastern coast of Madagascar for two days at this time, bringing heavy rains and strong surf to Madagascar and the two major Mascarene Islands, Reunion and Mauritius. The storm seemed to be staying away from settled areas, but reports from the Joint Typhoon Warning Center [ https://metocph.nmci.navy.mil/jtwc.php ] and U.K. Accuweather [ http://ukie.accuweather.com/ ] noted strong surf on the coast and island shorelines, as well as heavy rain. This same area was brushed by Cyclone Favio [ http://earthobservatory.nasa.gov/NaturalHazards/natural_hazards_v2.php3?img_id=14136 ] just days before, and it suffered a series of severe storms and cyclones in preceding months. Unlike Favio, Gamede was predicted to continue on its generally southward track and not turn towards mainland Africa. This photo-like image was acquired by the Moderate Resolution Imaging Spectroradiometer (MODIS) [ http://modis.gsfc.nasa.gov/ ] on the Aqua [ http://aqua.nasa.gov/ ] satellite on February 26, 2007, at 11:50 a.m. local time (9:50 UTC). The storm was a mature and powerful tropical cyclone, with a well-defined eye at its center and far-reaching, tightly wound spiral arms. According to the University of Hawaii's Tropical Storm Information Center, [ http://www.solar.ifa.hawaii.edu/Tropical/ ] Cylone Gamede has sustained winds of 175 kilometers per hour (110 miles per hour) around the eyewall at the time this image was acquired. Forecasts at the time called for the storm to avoid landfall, but to continue its grazing path between the Mascarene Islands and Madagascar, with winds continuing to intensify as the storm traveled south over warm waters. NASA image by Jesse Allen, using data provided courtesy of the MODIS Rapid Response Team, [ http://rapidfire.sci.gsfc.nasa.gov ] Goddard Space Flight Center. |
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Tropical Cyclone Gamede
| Title |
Tropical Cyclone Gamede |
| Description |
Tropical Cyclone Gamede was sitting in the western Indian Ocean off the shore of Madagascar on February 25, 2007. This powerful storm had been bringing heavy rains and strong surf to eastern Madagascar and the two major Mascarene Islands of Reunion and Mauritius. No settled land areas were experiencing the full brunt of of the sustained winds in the eyewall of the storm (reported at 195 kilometers per hour (120 miles per hour) by the Joint Typhoon Warning Center, [ https://metocph.nmci.navy.mil/jtwc.php ]) but damaging winds of 60 to 100 km/hr were recorded on the islands. One rainfall gauge measured totals as high as 47 centimeters over the three days Gamede was in the area, according to U.K. Accuweather. [ http://ukie.accuweather.com/ ] This photo-like image was acquired by the Moderate Resolution Imaging Spectroradiometer (MODIS) [ http://modis.gsfc.nasa.gov/ ] on NASA's Aqua [ http://aqua.nasa.gov/ ] satellite on February 25, 2007, at 11:50 a.m. local time (9:50 UTC), as the storm sat in the region between the small islands and Madagascar. At that time, it appeared the storm would head roughly south, bringing more winds and rain to the Mascarene Islands but not coming ashore onto Madagascar. Since the island had been pummeled by a series of tropical cyclones and storms in preceding months, Gamede was being watched with great care and concern by residents of the islands. The image provided above is at 1 kilometer resolution, less than the full level of detail possible from the MODIS instrument. The MODIS Rapid Response System provides this image at additional resolutions. [ http://rapidfire.sci.gsfc.nasa.gov/gallery/?2007056-0225/ ] Their image collection also includes the distant, but neighboring Cyclone Humba in the central Indian Ocean. NASA image by Jeff Schmaltz, MODIS Rapid Response Team, [ http://rapidfire.sci.gsfc.nasa.gov ] Goddard Space Flight Center. |
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Tropical Cyclone Gamede
| Title |
Tropical Cyclone Gamede |
| Description |
Tropical Cyclone Gamede was off the shore of Madagascar not far from the Mascarene Islands of Réunion and Mauritius on February 23, 2007, when it was observed by NASA's s QuikSCAT [ http://winds.jpl.nasa.gov/missions/quikscat/index.cfm ] satellite at 11:21 p.m. local time (2:21 UTC, February 24). The storm was not passing over any land nor anticipated to do so, according to the Joint Typhoon Warning Center, [ https://metocph.nmci.navy.mil/jtwc.php ] but it brought storm surge to coastal communities in Madagascar and the Mascarene Islands, and very heavy rain fell in several areas. This data visualization of QuikSCAT's observations shows Cyclone Gamede and its spiral pattern of winds. The image shows wind speed in color and wind direction with small barbs. White barbs point to areas of heavy rain. Gamede was well-formed, with winds spiraling around a distinct, calmer eye. This pattern is typical of tropical cyclones. Since the storm was in the Southern Hemisphere, the Coriolos force, which gives all cyclones their spin, turned Gamede clockwise, the opposite direction to hurricanes and typhoons that form in the Northern Hemisphere. According to the University of Hawaii's Tropical Storm Information Center, [ http://www.solar.ifa.hawaii.edu/Tropical/tropical.html ] Cyclone Gamede had sustained winds around 90 knots (165 kilometers per hour, 103 miles per hour) at the time of the QuikSCAT observations. Measurements of the actual wind strength of cyclones measured near the surface or from aircraft often document sustained winds higher than those estimated by QuikSCAT. QuikSCAT uses a scatterometer, which sends pulses of microwave energy through the atmosphere to the ocean surface and measures the strength of signal that bounces back from the wind-roughened surface. The energy of the microwave pulses changes depending on wind speed and direction, giving scientists a way to monitor wind around the world. This technique does not work over land, but allows measurements in storms over oceans. Tropical cyclones, however, are difficult to measure. To relate the strength of the signal that bounces back to the radar to actual wind speed, scientists compare measurements taken from buoys or other ground stations to data the satellite acquired at the same time and place. Because the high wind speeds generated by cyclones are rare, scientists do not have enough information to know how to translate data from the satellite for wind speeds above 50 knots (about 93 km/hr or 58 mph). Also, the unusually heavy rain found in a cyclone distorts the microwave pulses in a number of ways, making a conversion to exact wind speed difficult. Instead, the scatterometer provides a general picture of the relative wind speeds within the storm and shows wind direction. NASA image courtesy of David Long, Brigham Young University, on the QuikSCAT Science Team, [ http://winds.jpl.nasa.gov/ ] and the Jet Propulsion Laboratory. |
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Tropical Cyclone Jaya
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Tropical Cyclone Jaya |
| Description |
Tropical Cyclone Jaya came ashore in northern Madagascar in the morning of April 2, 2007 at around 11:00 a.m. local time (08:00 UTC). The storm formed in the Indian Ocean on March 30 and traveled westward toward Madagascar as predicted. What was not predicted, however, was its explosive growth in power from a strong tropical storm to a powerful Category 3 cyclone [ http://www.nhc.noaa.gov/aboutsshs.shtml ] in just 36 hours, according to figures provided by the University of Hawaii's Tropical Storm Information Center. [ http://www.solar.ifa.hawaii.edu/Tropical/tropical.html ]Fortunately, the intensification took place while Jaya was still far from Madagascar. This photo-like image was acquired by the Moderate Resolution Imaging Spectroradiometer (MODIS) [ http://modis.gsfc.nasa.gov/ ] on the Aqua [ http://aqua.nasa.gov/ ] satellite on April 3, 2007, at 1:15 p.m. local time (10:15 UTC). The storm was a tropical cyclone with a circular shape, but no distinct eye at its center. According to the University of Hawaii's Tropical Storm Information Center, [ http://www.solar.ifa.hawaii.edu/Tropical/ ] Cyclone Jaya's sustained winds had fallen in strength to roughly 125 kilometers per hour (80 mph) at the time this image was acquired. When the storm made landfall on Madagascar, sustained winds were around 150 kilometers per hour (90 miles per hour), a marked change from 200 km/hr (125 mph) just twelve hours earlier. While much weakened, Jaya remained a powerful storm. Furthermore, it struck the northern part of Madagascar where a series of other cyclones have also come ashore in recent months. Forecasters were concerned that Jaya might reform after crossing the island and head inland into Mozambique, where residents are recovering from floods caused by recent heavy rains. The high-resolution image provided above is at MODIS' full spatial resolution (level of detail) of 250 meters per pixel. The MODIS Rapid Response System provides this image at additional resolutions. [ http://rapidfire.sci.gsfc.nasa.gov/gallery/?2007093-0403/Jaya.A2007093.1015 ] You can download a 250-meter-resolution Cyclone Jaya KMZ file [ http://earthobservatory.nasa.gov/NaturalHazards/Archive/Apr2007/Jaya.A2007093.1015.250m.kmz ] for use with Google Earth. [ http://earth.google.com/download-earth.html ] NASA image by Jeff Schmaltz, MODIS Rapid Response Team, [ http://rapidfire.sci.gsfc.nasa.gov ] Goddard Space Flight Center. |
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