Article Type:
Research Article

A Pronounced Upper-Tropospheric Warm Anomaly Encountered by the NOAA G-IV Aircraft in the Vicinity of Deep Convection

Robert Rogers Cooperative Institute of Marine and Atmospheric Studies, Rosenstiel School of Marine and Atmospheric Science, University of Miami, Miami, Florida

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Sim Aberson NOAA/AOML Hurricane Research Division, Miami, Florida

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John Kaplan NOAA/AOML Hurricane Research Division, Miami, Florida

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Stan Goldenberg NOAA/AOML Hurricane Research Division, Miami, Florida

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Print Publication:
01 Jan 2002
DOI:
https://doi.org/10.1175/1520-0493(2002)130<0180:APUTWA>2.0.CO;2
Page(s):
180–187
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Abstract

Recent flights near deep convection by the National Oceanic and Atmospheric Administration's Gulfstream-IV surveillance aircraft have occasionally experienced significant positive temperature anomalies that sometimes impact the aircraft performance. One such event occurred over the Bahamas on 23 August 1999. During a 20-s time period, when the plane was cruising at an altitude of 175 hPa, the flight-level ambient temperature rose 15°C and returned to ambient values, concurrent with significant fluctuations in the horizontal and vertical winds. Large temperature anomalies such as that reported here can cause the avionics on the aircraft to compensate with a sudden decrease in air speed and a loss of altitude. Possible explanations for this anomaly include instrument error and convectively forced gravity waves or upper-level subsidence.

Corresponding author address: Dr. Robert F. Rogers, Cooperative Institute for Marine and Atmospheric Studies, NOAA/AOML, 4301 Rickenbacker Cswy., Miami, FL 33149. Email: rogers@aoml.noaa.gov

Abstract

Recent flights near deep convection by the National Oceanic and Atmospheric Administration's Gulfstream-IV surveillance aircraft have occasionally experienced significant positive temperature anomalies that sometimes impact the aircraft performance. One such event occurred over the Bahamas on 23 August 1999. During a 20-s time period, when the plane was cruising at an altitude of 175 hPa, the flight-level ambient temperature rose 15°C and returned to ambient values, concurrent with significant fluctuations in the horizontal and vertical winds. Large temperature anomalies such as that reported here can cause the avionics on the aircraft to compensate with a sudden decrease in air speed and a loss of altitude. Possible explanations for this anomaly include instrument error and convectively forced gravity waves or upper-level subsidence.

Corresponding author address: Dr. Robert F. Rogers, Cooperative Institute for Marine and Atmospheric Studies, NOAA/AOML, 4301 Rickenbacker Cswy., Miami, FL 33149. Email: rogers@aoml.noaa.gov

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  • Aberson, S. D., and J. L. Franklin, 1999: Impact on hurricane track and intensity forecasts of GPS dropwindsonde observations from the first-season flights of the NOAA Gulfstream-IV jet aircraft. Bull. Amer. Meteor. Soc, 80 , 421–427.

    • Search Google Scholar
    • Export Citation

  • Alexander, M. J., and L. Pfister, 1995: Gravity wave momentum flux in the lower stratosphere over convection. Geophys. Res. Lett, 22 , 2029–2032.

    • Search Google Scholar
    • Export Citation

  • Alexander, M. J., J. R. Holton, and D. R. Durran, 1995: The gravity wave response above deep convection in a squall line simulation. J. Atmos. Sci, 52 , 2212–2226.

    • Search Google Scholar
    • Export Citation

  • Black, M., A. B. Damiano, and S. R. White, 2000: The first eyewall penetration by the NOAA G-IV aircraft. Preprints, 24th Conf. on Hurricanes and Tropical Meteorology, Fort Lauderdale, FL, Amer. Meteor. Soc., 175–176.

    • Search Google Scholar
    • Export Citation

  • Burpee, R. W., J. L. Franklin, S. J. Lord, R. E. Tuleya, and S. D. Aberson, 1996: The impact of Omega dropwindsondes on operational hurricane track forecast models. Bull. Amer. Meteor. Soc, 77 , 925–933.

    • Search Google Scholar
    • Export Citation

  • Foley, G., 1998: A marked upper tropospheric temperature anomaly observed by an aircraft near a thunderstorm over inland Western Australia. Aust. Meteor. Mag, 47 , 321–326.

    • Search Google Scholar
    • Export Citation

  • Hock, T. F., and J. L. Franklin, 1999: The NCAR GPS dropwindsonde. Bull. Amer. Meteor. Soc, 80 , 407–420.

  • Holland, G. J., T. D. Keenan, and G. D. Crane, 1984: Observations of a phenomenal temperature perturbation in Tropical Cyclone Kerry (1979). Mon. Wea. Rev, 112 , 1074–1082.

    • Search Google Scholar
    • Export Citation

  • Holton, J. R., 1979: An Introduction to Dynamic Meteorology. 2d ed. International Geophysics Series, Volume 23, Academic Press, 391 pp.

  • Hooke, W. H., 1986: Gravity waves. Mesoscale Meteorology and Forecasting, P. S. Ray, Ed., Amer. Meteor. Soc., 272–288.

  • Hoxit, L. R., C. F. Chappell, and J. M. Fritsch, 1976: Formation of mesolows or pressure troughs in advance of cumulonimbus clouds. Mon. Wea. Rev, 104 , 1419–1428.

    • Search Google Scholar
    • Export Citation

  • Pandya, R. E., and D. R. Durran, 1996: The influence of convectively generated thermal forcing on the mesoscale circulation around squall lines. J. Atmos. Sci, 53 , 2924–2951.

    • Search Google Scholar
    • Export Citation

  • Pfister, L., K. R. Chan, T. P. Bui, S. Bowen, M. Legg, B. Gary, K. Kelly, M. Proffitt, and W. Starr, 1993: Gravity waves generated by a tropical cyclone during the STEP Tropical Field Program: A case study. J. Geophys. Res, 98 , 8611–8638.

    • Search Google Scholar
    • Export Citation
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