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Sept. 23, 1998: (this is the 19th in a series of stories covering the ongoing CAMEX mission to hunt hurricane data in a way not done since the 50s. Other stories are linked in below.) Mother Nature treated hurricane researchers to a rare light show as they flew the last mission of the most ambitious hurricane study campaign in the Atlantic Ocean. Rarely seen lightning fields and purple sprites were detected in the eye of the hurricane by the ER-2 pilot as he flew more than 19.8 km (65,000 ft) above the Atlantic. The third Convection and Moisture Experiment (CAMEX-3) officially ends today, although that's not the end of the program. With an extensive collection of data, the scientists and their colleagues will be busy analyzing what they recorded and extracting a better understanding of how hurricanes form and energize as they move across the ocean.
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Ironically, the team may have to pack quickly and evacuate, with no time for lengthy farewells (the group photos were already done Saturday) because Georges is threatening Patrick Air Force Base on Florida's east coast, where the CAMEX-3 team is based. The evacuation of the Florida Keys has already been ordered. The hurricane's farewell gift - the lightning and sprites - are a recently discovered phenomenon that NASA's Global Hydrology and Climate Center, coordinator of CAMEX-3, has been studying. Red sprites and blue jets, as they are known, were seen by high-altitude pilots and Space Shuttle crews in the 1980s, perhaps earlier, but most observers were unsure of what they saw and did not report the events. Sprites and jets are very faint and can be recorded only with cameras using image intensifiers (see sidebar). Observations from the Shuttle in 1989-91 and aircraft videotapes of sprites in 1993 confirmed their existence. The exact cause remains a mystery, although they appear to be a part of the global electrical circuit.
Tuesday's Georges synoptic/water vapor inflow flight was a success. The hurricane had already made landfall over Hispaniola and was impacting the mountains there. Although Tuesday was the DC-8 Airborne Laboratory's last CAMEX-3 flight - the team sent special thanks to the flight crew for its excellent support. Monday's Georges eye wall flight was a success. Georges showed many unique characteristics including large cloud turrets, variable eye wall winds, and wind speeds up to 148 km/h (80 knots; 92 mph) at 10 km (33,000 ft) altitude. The eye wall pattern was also significantly displaced from the radar eye wall location unlike those seen with Bonnie, Danielle, or Earl. |
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Hurricane Georges is smaller than Bonnie, the hurricane that NASA and its partners closely studied earlier this season, but is still quite deadly. From its first calibration flight on Aug. 8 through today, the CAMEX-3 team - which includes aircraft from the National Oceanic and Atmospheric Administration and coordination with the U.S. Air Force Hurricane Hunters - has studied Hurricanes Bonnie, Danielle, Earl and now, Georges. The project also combined resources and objectives with the Texas and Florida Underflight (TEFLUN-B) campaign in which the same aircraft and instruments measured storms - not necessarily hurricanes - the validate the instruments on the Tropical Rainfall Measuring Mission satellite as it flew overhead. A complete listing of CAMEX-3 and TEFLUN-B missions is given below. |
Note: More details are available in the NASA press release describing CAMEX-3. Check back as hurricane season progresses. We will post science updates as the campaign develops. PIX: High resolution scans of 35mm camera photos from the CAMEX-3 campaign are available from Public Affairs Office at NASA headquarters. Please call the NASA Headquarters Photo Department at 202-358-1900, or contact Bill Ingalls at bingalls@hq.nasa.gov. Explanations of sprites and additional images are available from the Global Hydrology and Climate Center and the University of Alaska.
CAMEX Series Headlines August 12:
Overview CAMEX story , describes
the program in detail. NCAR has an extensive writeup on the GPS dropsondes used in CAMEX-3 and other atmospheric campaigns. A new study - not related to CAMEX-3 - by the Arizona State University suggests a link between hurricanes in the northwest Atlantic and air pollution. |
August |
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5 | ER-2 arrives at Patrick Air Force Base |
6 | No-fly day |
7 | No-fly day |
8 | Shakedown over Andros Island Ground Station. The convective thunderstorm was exactly below the ER-2 flight track as predicted and we should have some good data from the flight. |
9 | No-fly day |
10 | DC-8 flies from Dryden Flight Research Center to Patrick AFB |
11 | No-fly day |
12 | No-fly day |
13 | TEFLUN B: Deep convection measurements over Melbourne, Fla., area. The TEFLUN-B ground coordination flight seems to be a large success. We had all three aircraft in stacked formation, on coordinated lines, through an active storm, instruments working well, with a TRMM satellite overpass. |
14 | No-fly day |
15 | TEFLUN B: Deep convection measurements over central Florida |
16 | No-fly day |
17 | No-fly day |
18 | No-fly day |
19 | No-fly day |
20 | TEFLUN B: Convection east of Cape Canaveral. Today's TEFLUN-B mission was highly successful. The ER-2 was canceled due to high cross winds. The DC-8 and UND Citation accomplished major goals in the stratiform rain environment while the TRMM satellite passed overhead. The NASA aircraft are on alert for a CAMEX-3, tropical storm Bonnie, flight tomorrow. The UND Citation is on alert for a possible TEFLUN-B mission. |
21 | CAMEX-3: Tropical Storm Bonnie synoptic flow measurements. The ER-2 was canceled due to high winds. The DC-8 did fly a synoptic flow mission on tropical storm Bonnie. Everything seems to be a success. Patrick AFB is officially on a HURCON 4 alert. The AF Battle Staff will meet at 1000 tomorrow. We need to prepare to evacuate the base tomorrow If we are not forced to evacuate, tomorrow will be a no fly day. Stay tuned. |
22 | TEFLUN B: Citation II TEFLUN mission was successful today; the NASA DC-8 and ER-2 had no-fly day. Patrick AFB issued a HURCON 3 posted at 1300 EDT. Plans are to perform another Bonnie mission tomorrow with DC-8 and ER-2. If HURCON 2 is issued, we will have to evacuate the area immediately. The aircraft will be sent to Warner-Robbins AFB, Macon, GA. |
23 | CAMEX-3: Hurricane Bonnie eye wall #1. DC-8 and ER-2 made extremely successful flights over the eye wall of hurricane Bonnie in coordination with the NOAA aircraft. They both overflew the Andros Island site on the return from Bonnie. Monday we will make another flight over hurricane Bonnie, planning closer coordination with NOAA aircraft Flight tracks over the hurricane will be similar to the ones flown on Sunday. |
24 | CAMEX-3: Hurricane Bonnie eye wall #2. CAMEX bagged another highly successful overflight of Hurricane Bonnie in conjunction with the NOAA WP-3 aircraft. The aircraft will stand down Tuesday, Aug. 25. |
25 | No-fly day |
26 | CAMEX-3: Hurricane Bonnie landfall. Another extremely successful flight day. Both ER-2 and DC-8 overflew Bonnie as it made landfall. There were three TRMM overpasses during the flight with the earliest overpass almost directly over the eye wall. Both NOAA Orions also flew coordinated patterns with the NASA aircraft. Tomorrow will be a no fly day and Friday a tentative hard down day. We anticipate the earliest opportunity for a Hurricane Danielle flight on Saturday, 29 August. |
27 | TEFLUN B: UND Citation II had a successful flight studying convection over the S-POL site. |
28 | No-fly day |
29 | CAMEX-3: Hurricane Danielle. Vortex motion and evolution and moisture inflow measurements by DC-8. |
30 | CAMEX-3: Hurricane Danielle. Vortex motion and evolution and moisture inflow measurements by DC-8. |
31 | No-fly day |
September |
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1 | All aircraft will stand up for possible flights on hurricane Earl tomorrow. Science objectives will include both TEFLUN-B and CAMEX-3 objectives. |
2 | CAMEX-3: Hurricane Earl. Today's flight through the rain bands of Earl was a big success. Both TEFLUN and CAMEX objectives were met as tropical storm Earl was upgraded to a hurricane prior to launch. Tomorrow will be a no fly day. |
3 | No-fly day. |
4 | Today's NASA ER2 & DC8 TEFLUN-B flights were canceled due to weather conditions being too dynamic or nonexistent. All aircraft will stand up for TEFLUN objective flights tomorrow. |
5 | TEFLUN B: Todays TEFLUN flights studying stratiform rain were a success. |
6 | TEFLUN B: Todays TEFLUN flights studying stratiform rain were a success. |
7 | No-fly day. |
8 | TEFLUN B: Today the ER-2 and Citation flew developing convection over SPOL for three hours and twenty five minutes. |
9 | Today's flights were canceled. |
10 | Today's flights were canceled due to underdeveloped convection. |
11 | Todays flight was canceled because the easterly flow remains and little convection is expected within this scenario. With this expected to remain, we will have a hard down day tomorrow. Our next flight is expected to be a TEFLUN flight on Sunday but with the possibility of an Andros flight as a back-up. |
12 | No fly day. |
13 | Today's Andros ground calibration/validation seems to be a success. We will stand up for TEFLUN flights tomorrow afternoon. |
14 | TEFLUN B: Today's ER-2 flight was canceled due to predicted high cross winds. The DC-8 and Citation, however, did fly the TEFLUN mission over convective cells just off the coast of the Cape. Tomorrow all aircraft will stand up for coordinated TEFLUN flights. |
15 | TEFLUN B: The ER-2 flight scrubbed today due to high predicted cross winds. The DC-8 and Citation did fly their last coordinated TEFLUN mission for this experiment. Tomorrow will be a no-fly day for the NASA aircraft, but the Citation will depart Patrick. |
16 | No-fly day |
17 | TEFLUN B: Today's ER-2 and DC-8 TEFLUN flights were an excellent study of good convective lines and large stratiform regions. Tomorrow and Saturday will be no-fly days and as long as hurricane Georges doesn't hit Mach speed, Sunday will be an all day science meeting. |
18 | No-fly day |
19 | Science Symposium; No-fly day. |
20 | No-fly day |
21 | CAMEX-3: Hurricane Georges. Successful eye wall flight into Georges. |
22 | CAMEX-3: Hurricane Georges. Successful synoptic inflow mission around Georges. |
23 | CAMEX-3 concludes. |
CAMEX-3 - the third Convection and Moisture Experiment - is an interagency project to measure hurricane dynamics at high altitude, a method never employed before over Atlantic storms. From this, scientists hope to understand better how hurricanes are powered and to improve the tools they use to predict hurricane intensity. An overview story (Aug. 12, 1998) describes the program in detail. The study is part of NASA's Earth Science enterprise to better understand the total Earth system and the effects of natural and human-induced changes on the global environment. A midterm story (Aug. 31, 1998) reviews the first month of operations and the windfall of data. Because meteorology and aeronautics first used modified nautical charts, their data bases are in nautical miles and knots (nautical miles per hour). In these stories, we use Standard International ("metric") units first, and give more familiar measurements in English units and the original measurements in nautical units. Because of rounding and because the wind speeds originally are expressed in knots, km/h speeds to knots may be slightly different from the numbers in the story.
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Web Links |
CAMEX-3 home page contains
links to daily flight operations and instrument descriptions.
Lightning Imaging Sensor aboard the TRMM satellite observes lightning from above the clouds - and my lead to better warnings on the ground. MACAWS uses the Doppler effect (red and blue shifts) to measure wind velocity. SPARCLE is a Space Shuttle experiment set for 2001 to demonstrate laser wind measurement from space. |
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