Results 1 - 10
of
21
A study of mesoscale gravity waves over the North Atlantic with satellite observations and a mesoscale model.
- J. Geophys. Res.,
, 2004
"... ..."
(Show Context)
Mesoscale gravity wave variances from AMSU-A radiances
- Geophys. Res. Lett
"... [1] A variance analysis technique is developed here to extract gravity wave (GW) induced temperature fluctuations from NOAA AMSU-A (Advanced Microwave Sounding Unit-A) radiance measurements. By carefully removing the instrument/measurement noise, the algorithm can produce reliable GW variances with ..."
Abstract
-
Cited by 13 (3 self)
- Add to MetaCart
[1] A variance analysis technique is developed here to extract gravity wave (GW) induced temperature fluctuations from NOAA AMSU-A (Advanced Microwave Sounding Unit-A) radiance measurements. By carefully removing the instrument/measurement noise, the algorithm can produce reliable GW variances with the minimum detectable value as small as 0.1 K2. Preliminary analyses with AMSU-A data showGWvariancemaps in the stratosphere have very similar distributions to those found with the UARS MLS (Upper Atmosphere Research Satellite Microwave Limb Sounder). However, the AMSU-A offers better horizontal and temporal resolution for observing regional GW variability, such as activity over sub-Antarctic islands. INDEX TERMS: 0350
2004: On the influences of vertical wind shear on symmetric tropical cyclone structure derived from
"... Axisymmetric temperatures and gradient-balanced winds associated with tropical cyclones derived from the Advanced Microwave Sounding Unit are stratified by the 24-h averaged vector difference of the horizontal wind between 200 and 850 hPa (or vertical wind shear). Using 186 total cases that are limi ..."
Abstract
-
Cited by 13 (0 self)
- Add to MetaCart
Axisymmetric temperatures and gradient-balanced winds associated with tropical cyclones derived from the Advanced Microwave Sounding Unit are stratified by the 24-h averaged vector difference of the horizontal wind between 200 and 850 hPa (or vertical wind shear). Using 186 total cases that are limited to tropical cyclones with intensities greater than 33 m s21 (or mature) and are located over sea surface temperatures greater than 26.48C, vertical wind shear–based composites are created. Results show that as the vertical wind shear increased, the upper-level warm-core structure associated with the tropical cyclone descended, resulting in a shallower balanced vortex. These observationally based results are presented in the context of recent mesoscale modeling results of the effect of shear on tropical cyclone structure. 1.
Error Structure and Atmospheric Temperature Trends in Observations from the Microwave Sounding Unit
, 2007
"... The Microwave Sounding Unit (MSU) onboard the National Oceanic and Atmospheric Administration polar-orbiting satellites measures the atmospheric temperature from the surface to the lower stratosphere under all weather conditions, excluding precipitation. Although designed primarily for monitoring we ..."
Abstract
-
Cited by 7 (0 self)
- Add to MetaCart
The Microwave Sounding Unit (MSU) onboard the National Oceanic and Atmospheric Administration polar-orbiting satellites measures the atmospheric temperature from the surface to the lower stratosphere under all weather conditions, excluding precipitation. Although designed primarily for monitoring weather processes, the MSU observations have been extensively used for detecting climate trends, and calibration errors are a major source of uncertainty. To reduce this uncertainty, an intercalibration method based on the simultaneous nadir overpass (SNO) matchups for the MSU instruments on satellites NOAA-10,-11,-12, and-14 was developed. Due to orbital geometry, the SNO matchups are confined to the polar regions, where the brightness temperature range is slightly smaller than the global range. Nevertheless, the resulting calibration coefficients are applied globally to the entire life cycle of an MSU satellite. Such intercalibration reduces intersatellite biases by an order of magnitude compared to prelaunch calibration and, thus, results in well-merged time series for the MSU channels 2, 3, and 4, which respectively represent the deep layer temperature of the midtroposphere (T2), tropopause (T3), and lower stratosphere (T4). Focusing on the global atmosphere over ocean surfaces, trends for the SNO-calibrated T 2,T 3, and T 4 are, respectively, 0.21 6 0.07, 0.08 6 0.08, and 20.38 6 0.27 K decade 21 from 1987 to 2006. These trends are
Potential of Advanced Microwave Sounding Unit-A (AMSU-A) and AMSU-B measurements for atmospheric temperature and humidity profiling over
, 2005
"... [1] A neural network retrieval method has been applied to investigate AMSU-A/ AMSU-B atmospheric temperature and humidity profiling capabilities over land. The retrieval method benefits from a reliable estimate of the land emissivity and skin temperature as well as first guess information regarding ..."
Abstract
-
Cited by 3 (1 self)
- Add to MetaCart
[1] A neural network retrieval method has been applied to investigate AMSU-A/ AMSU-B atmospheric temperature and humidity profiling capabilities over land. The retrieval method benefits from a reliable estimate of the land emissivity and skin temperature as well as first guess information regarding the temperature-humidity profiles. It has been applied on a large geographic area (60°W–60°E, 60°S–60°N) and atmospheric situations (winter and summer). The retrieved RMS errors are within 2 K and 9 % in temperature and relative humidity, respectively. Regardless of scanning conditions, vegetation types, and atmospheric situations, the algorithm retrieval results are satisfactory for both temperature and relative humidity. The retrieval approach has been evaluated by comparison with available in situ measurements.
Using Opaque Microwave Bands
, 2004
"... This thesis describes the use of opaque microwave bands for global estimation of precipitation rate. An algorithm was developed for estimating instantaneous precip-itation rate for the Advanced Microwave Sounding Unit (AMSU) on the NOAA-15, NOAA-16, and NOAA-17 satellites, and the Advanced Microwave ..."
Abstract
- Add to MetaCart
(Show Context)
This thesis describes the use of opaque microwave bands for global estimation of precipitation rate. An algorithm was developed for estimating instantaneous precip-itation rate for the Advanced Microwave Sounding Unit (AMSU) on the NOAA-15, NOAA-16, and NOAA-17 satellites, and the Advanced Microwave Sounding Unit and Humidity Sounder for Brazil (AMSU/HSB) aboard the NASA Aqua satellite. The algorithm relies primarily on channels in the opaque 54-GHz oxygen and 183-GHz water vapor resonance bands. Many methods for estimating precipitation rate using surface-sensitive microwave window channels have been developed by others. The algorithm involves a set of signal processing components whose outputs are fed into a neural net to produce a rain rate estimate for each 15-km spot. The signal processing components utilize techniques such as principal component analysis for characterizing groups of channels, spatial filtering for cloud-clearing brightness tem-
Atmospheric
"... doi:10.5194/nhess-13-1959-2013 © Author(s) 2013. CC Attribution 3.0 License. ..."
Abstract
- Add to MetaCart
doi:10.5194/nhess-13-1959-2013 © Author(s) 2013. CC Attribution 3.0 License.
A Comparison of Observed and Simulated Brightness Temperatures from Two Radiative Transfer Models of RTTOV and CRTM
"... Abstract: The radiative transfer for TIROS operational vertical sounder (RTTOV) and the community radiative transfer model (CRTM) are two fast radiative transfer models (RTM) that are used as observation operators in numerical weather prediction (NWP) systems. This study compares the basic structure ..."
Abstract
- Add to MetaCart
Abstract: The radiative transfer for TIROS operational vertical sounder (RTTOV) and the community radiative transfer model (CRTM) are two fast radiative transfer models (RTM) that are used as observation operators in numerical weather prediction (NWP) systems. This study compares the basic structure and input data of the two models. With data from Advanced Microwave Sounding Unit-A (AMSU-A), which has channels of various frequencies, observed brightness temperature (TB) and simulated TBs from the two models are compared over the ocean surface in two cases-one where cloud information is included and the other without it. Regarding AMSU-A sounding channels (5-14), the two models produce no large significant differences in their calculated TB, but RTTOV produces smaller first guess (FG) departures (i.e., better results) in window and near-surface sounding channels than does CRTM. When adding cloud water and ice particles from Unified Model (UM), the TB bias between observations and simulations are reduced in both models and the
Nadir Correction of AIRS Radiances
, 2009
"... electronic reprint (preprint) with permission of American Meteorological Society. The paper can be found at ..."
Abstract
- Add to MetaCart
electronic reprint (preprint) with permission of American Meteorological Society. The paper can be found at
Services and Solution Group
"... Public reporting burden for the collection of information is estimated to average 1 hour per response, including the time for reviewing instructions, searching existing data sources, gathering and maintaining the data needed, and completing and reviewing the collection of information. Send comments ..."
Abstract
- Add to MetaCart
Public reporting burden for the collection of information is estimated to average 1 hour per response, including the time for reviewing instructions, searching existing data sources, gathering and maintaining the data needed, and completing and reviewing the collection of information. Send comments regarding this burden estimate or any other aspect of this collection of information, including suggestions for reducing this burden, to Washington Headquarters Services, Directorate for Information Operations and Reports, 1215 Jefferson Davis Highway, Suite 1204, Arlington VA 22202-4302. Respondents should be aware that notwithstanding any other provision of law, no person shall be subject to a penalty for failing to comply with a collection of information if it does not display a currently valid OMB control number. 1. REPORT DATE 17 DEC 2013 2. REPORT TYPE
