Transport of Water Vapor from Tropical Cyclones to the Upper Troposphere

This paper investigates the influence of tropical cyclones on water vapor concentrations in the upper atmosphere above these storms. We use independent data sets of tropical storm intensity, water vapor and lightning activity to investigate this relationship. Water vapor in the upper troposphere is a key greenhouse gas, with direct impacts on surface temperatures. Both the amount and altitude of water vapor impact the radiative balance and the greenhouse effect of the atmosphere. The water vapor enters the upper troposphere through deep convective storms, often associated with lightning activity. The intensity of the lightning activity represents the intensity of the convection in these storms, and hence the amount of water vapor transported aloft. In this paper, we investigate the role of tropical cyclones on the contribution of water vapor to the upper atmosphere moistening. Tropical cyclones are the largest most intense storms on Earth and can last for up to two weeks at a time. There is also evidence that the intensity of tropical cyclones is increasing, and will continue to increase, due to global warming. In this study we find that the maximum moistening of the upper atmosphere occurs at the 200 hPa level (~12 km altitude), with a lag of 1–2 days after the maximum sustained winds in the tropical cyclone. While the water vapor peaks after the maximum of the storm intensity, the lightning activity peaks before the maximum intensity of the storms, as shown previously. We show here that the absolute amount of water vapor in the upper troposphere above tropical storms increases linearly with the intensity of the storms. For every 10 hPa decrease in the minimum pressure of tropical storms, the specific humidity increases around 0.2 g/kg at the 200 hPa level.

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Effect of tropical cyclones on the Stratosphere-Troposphere Exchange observed using satellite observations over north Indian Ocean

10.5194/acp-2015-988 ◽

2016 ◽

Cited By ~ 3

Author(s):

M. Venkat Ratnam ◽

S. Ravindra Babu ◽

S. S. Das ◽

Ghouse Basha ◽

B. V. Krishnamurthy ◽

...

Keyword(s):

Water Vapor ◽

Indian Ocean ◽

Tropical Cyclones ◽

Lower Stratosphere ◽

North Indian Ocean ◽

Satellite Observations ◽

Upper Troposphere ◽

North West ◽

The North ◽

The Impact

Abstract. Tropical cyclones play an important role in modifying the tropopause structure and dynamics as well as stratosphere-troposphere exchange (STE) process in the Upper Troposphere and Lower Stratosphere (UTLS) region. In the present study, the impact of cyclones that occurred over the North Indian Ocean during 2007–2013 on the STE process is quantified using satellite observations. Tropopause characteristics during cyclones are obtained from the Global Positioning System (GPS) Radio Occultation (RO) measurements and ozone and water vapor concentrations in UTLS region are obtained from Aura-Microwave Limb Sounder (MLS) satellite observations. The effect of cyclones on the tropopause parameters is observed to be more prominent within 500 km from the centre of cyclone. In our earlier study we have observed decrease (increase) in the tropopause altitude (temperature) up to 0.6 km (3 K) and the convective outflow level increased up to 2 km. This change leads to a total increase in the tropical tropopause layer (TTL) thickness of 3 km within the 500 km from the centre of cyclone. Interestingly, an enhancement in the ozone mixing ratio in the upper troposphere is clearly noticed within 500 km from cyclone centre whereas the enhancement in the water vapor in the lower stratosphere is more significant on south-east side extending from 500–1000 km away from the cyclone centre. We estimated the cross-tropopause mass flux for different intensities of cyclones and found that the mean flux from stratosphere to troposphere for cyclonic stroms is 0.05 ± 0.29 × 10−3 kg m−2 and for very severe cyclonic stroms it is 0.5 ± 1.07 × 10−3 kg m−2. More downward flux is noticed in the north-west and south-west side of the cyclone centre. These results indicate that the cyclones have significant impact in effecting the tropopause structure, ozone and water vapour budget and consequentially the STE in the UTLS region.

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Tropical cyclone eyewall thunderstorms as a driver of upper tropospheric water vapor increases

10.5194/egusphere-egu21-4269 ◽

2021 ◽

Author(s):

Colin Price ◽

Tair Plotnik ◽

Anirban Guha ◽

Joydeb Saha`

Keyword(s):

Global Warming ◽

Water Vapor ◽

Tropical Cyclones ◽

Longwave Radiation ◽

Maximum Intensity ◽

Lightning Activity ◽

Maximum Enhancement ◽

The Earth ◽

The Future ◽

The Impact

<p>Tropical cyclones have been observed in recent years to be increasing in intensity due to global warming, and projections for the future are for further shifts to stronger tropical cyclones, while the changes in the number of storms is less certain in the future.&#160; These storms have been shown to exhibit strong lightning activity in the eyewall and rainbands, and some studies (Price et al., 2009) showed that the lightning activity peaks before the maximum intensity of the tropical cyclones.&#160; Now we have investigated the impact of these tropical storms on the upper tropospheric water vapor (UTWV) content.&#160; Using the ERA5 reanalysis product from the ECMWF center, together with lightning data from the ENTLN network, we show that the lightning activity in tropical cyclones is closely linked to the increase in UTWV above these storms.&#160; We find the maximum enhancement in UTWV occurs between the 100-300 mb pressure levels, with a lag of 0-2 days after the peak of the storm intensity (measured by the maximum sustained winds in the eyewall).&#160; The lightning activity peaks before the storm reaches its maximum intensity, as found in previous studies.&#160; The interest in UTWV concentrations is due to the strong positive feedback that exists between the amounts of UTWV and surface global warming.&#160; Water Vapor is a strong greenhouse gas which is most efficient in trapping in longwave radiation emitted from the Earth in the upper troposphere.&#160; Small changes in UTWV over time can result in strong surface warming.&#160; If tropical cyclones increase in intensity in the future, this will likely result in increases in UTWV, reducing the natural cooling ability of the Earth.&#160; Lightning may be a useful tool to monitor these changes.</p>

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A Multi-sensor Upper Tropospheric Ozone Product (MUTOP) based on TES ozone and GOES water vapor: derivation

Atmospheric Chemistry and Physics Discussions ◽

10.5194/acpd-10-30055-2010 ◽

2010 ◽

Vol 10 (12) ◽

pp. 30055-30087 ◽

Cited By ~ 2

Author(s):

S. R. Felker ◽

J. L. Moody ◽

A. J. Wimmers ◽

G. Osterman ◽

K. Bowman

Keyword(s):

Water Vapor ◽

Potential Vorticity ◽

Tropospheric Ozone ◽

Forecast Model ◽

Scientific Basis ◽

Specific Humidity ◽

Upper Troposphere ◽

Weather Patterns ◽

Mixing Ratios ◽

Spatial Coverage

Abstract. The Tropospheric Emission Spectrometer (TES), a hyperspectral infrared instrument on the Aura satellite, retrieves a vertical profile of tropospheric ozone. However, polar-orbiting instruments like TES provide limited nadir-view coverage. This work illustrates the value of these observations when taken in context with information about synoptic-scale weather patterns. The goal of this study is to create map-view products of upper troposphere (UT) ozone through the integration of TES ozone measurements with two synoptic dynamical tracers of stratospheric influence: specific humidity derived from the GOES Imager, and potential vorticity from an operational forecast model. As a mixing zone between tropospheric and stratospheric reservoirs, the upper troposphere (UT) exhibits a complex chemical makeup. Determination of ozone mixing ratios in this layer is especially difficult without direct in-situ measurement. However, it is well understood that UT ozone is correlated with dynamical tracers like low specific humidity and high potential vorticity. Blending the advantages of two remotely sensed quantities (GOES water vapor and TES ozone) is at the core of the Multi-sensor Upper Tropospheric Ozone Product (MUTOP). Our approach results in the temporal and spatial coverage of a geostationary platform, a major improvement over individual polar overpasses, while retaining TES's ability to characterize UT ozone. Results suggest that over 70% of TES-observed UT ozone variability can be explained by correlation with the two dynamical tracers. MUTOP reproduces TES retrievals across the GOES-West domain with a root mean square error (RMSE) of 19.2 ppbv. There are several advantages to this multi-sensor derived product approach: (1) it is calculated from 2 operational fields (GOES specific humidity and GFS PV), so the layer-average ozone can be created and used in near real-time; (2) the product provides the spatial resolution and coverage of a geostationary platform as it depicts the distribution of dynamically driven ozone in the UT; and (3) the 6 h temporal resolution of the imagery allows for the visualization of rapid movement of this dynamically-driven ozone in the UT. This paper presents the scientific basis and methodology behind the creation of this unique ozone product, as well as a statistical comparison of the derived product to a set of coincident TES observations.

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Multimodel Analysis of the Water Vapor Feedback in the Tropical Upper Troposphere

Journal of Climate ◽

10.1175/jcli3882.1 ◽

2006 ◽

Vol 19 (20) ◽

pp. 5455-5464 ◽

Cited By ~ 17

Author(s):

Ken Minschwaner ◽

Andrew E. Dessler ◽

Parnchai Sawaengphokhai

Keyword(s):

Water Vapor ◽

Relative Humidity ◽

Climate Models ◽

Global Climate ◽

Global Climate Models ◽

Sea Surface ◽

Specific Humidity ◽

Upper Troposphere ◽

The Mean ◽

Tropical Upper Troposphere

Abstract Relationships between the mean humidity in the tropical upper troposphere and tropical sea surface temperatures in 17 coupled ocean–atmosphere global climate models were investigated. This analysis builds on a prior study of humidity and surface temperature measurements that suggested an overall positive climate feedback by water vapor in the tropical upper troposphere whereby the mean specific humidity increases with warmer sea surface temperature (SST). The model results for present-day simulations show a large range in mean humidity, mean air temperature, and mean SST, but they consistently show increases in upper-tropospheric specific humidity with warmer SST. The model average increase in water vapor at 250 mb with convective mean SST is 44 ppmv K−1, with a standard deviation of 14 ppmv K−1. Furthermore, the implied feedback in the models is not as strong as would be the case if relative humidity remained constant in the upper troposphere. The model mean decrease in relative humidity is −2.3% ± 1.0% K−1 at 250 mb, whereas observations indicate decreases of −4.8% ± 1.7% K−1 near 215 mb. These two values agree within the respective ranges of uncertainty, indicating that current global climate models are simulating the observed behavior of water vapor in the tropical upper troposphere with reasonable accuracy.

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Observed and Simulated Upper-Tropospheric Water Vapor Feedback

Journal of Climate ◽

10.1175/2007jcli2142.1 ◽

2008 ◽

Vol 21 (13) ◽

pp. 3282-3289 ◽

Cited By ~ 29

Author(s):

A. Gettelman ◽

Q. Fu

Keyword(s):

Water Vapor ◽

General Circulation ◽

Circulation Model ◽

Specific Humidity ◽

Upper Troposphere ◽

Double Peak Structure ◽

Peak Structure ◽

Surface Temperatures ◽

Community Atmosphere Model ◽

Water Vapor Feedback

Abstract Satellite measurements from the Atmospheric Infrared Sounder (AIRS) in the upper troposphere over 4.5 yr are used to assess the covariation of upper-tropospheric humidity and temperature with surface temperatures, which can be used to constrain the upper-tropospheric moistening due to the water vapor feedback. Results are compared to simulations from a general circulation model, the NCAR Community Atmosphere Model (CAM), to see if the model can reproduce the variations. Results indicate that the upper troposphere maintains nearly constant relative humidity for observed perturbations to ocean surface temperatures over the observed period, with increases in temperature ∼1.5 times the changes at the surface, and corresponding increases in water vapor (specific humidity) of 10%–25% °C−1. Increases in water vapor are largest at pressures below 400 hPa, but they have a double peak structure. Simulations reproduce these changes quantitatively and qualitatively. Agreement is best when the model is sorted for satellite sampling thresholds. This indicates that the model reproduces the moistening associated with the observed upper-tropospheric water vapor feedback. The results are not qualitatively sensitive to model resolution or model physics.

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Impacts of tropical cyclones on the thermodynamic conditions in the tropical tropopause layer observed by A-Train satellites

Atmospheric Chemistry and Physics ◽

10.5194/acp-21-15493-2021 ◽

2021 ◽

Vol 21 (20) ◽

pp. 15493-15518

Author(s):

Jing Feng ◽

Yi Huang

Keyword(s):

Water Vapor ◽

Tropical Cyclone ◽

Tropical Cyclones ◽

Deep Convection ◽

Radiative Heating ◽

Radiative Cooling ◽

Radiative Balance ◽

Tropical Tropopause Layer ◽

Tropical Tropopause ◽

The Impact

Abstract. The tropical tropopause layer (TTL) is the transition layer between the troposphere and the stratosphere. Tropical cyclones may impact the TTL by perturbing the vertical distributions of cloud, temperature, and water vapor. This study combines several A-Train instruments, including radar from CloudSat, lidar from the Cloud-Aerosol Lidar and Infrared Pathfinder Satellite Observation (CALIPSO) satellite, and the Atmospheric Infrared Sounder (AIRS) on the Aqua satellite, to detect signatures of cyclone impacts on the distribution patterns of cloud, water vapor, temperature, and radiation by compositing these thermodynamic fields relative to the cyclone center location. Based on the CloudSat 2B-CLDCLASS-LIDAR product, this study finds that tropical cyclone events considerably increase the occurrence frequencies of TTL clouds, in the form of cirrus clouds above a clear troposphere. The amount of TTL cloud ice, however, is found to be mostly contributed by overshooting deep convection that penetrates the base of the TTL at 16 km. To overcome the lack of temperature and water vapor products in cloudy conditions, this study implements a synergistic method that retrieves temperature, water vapor, ice water content, and effective radius simultaneously by incorporating observations from AIRS, CloudSat, and CALIPSO. Using the synergistic method, we find a vertically oscillating pattern of temperature anomalies above tropical cyclones, with warming beneath the cloud top (around 16 km) and cooling above. Based on water vapor profiles retrieved by the synergistic method, we find that the layer integrated water vapor (LIWV) above 16 km is higher above tropical cyclones, especially above overshooting deep convective clouds, compared to climatological values. Moreover, we find that the longwave and net radiative cooling effect of clouds prevails within 1000 km of tropical cyclone centers. The radiative heating effects of clouds from the CloudSat 2B-FLXHR-LIDAR product are well differentiated by the collocated brightness temperature of an infrared window channel from the collocated AIRS L1B product. By performing instantaneous radiative heating rate calculations, we further find that TTL hydration is usually associated with radiative cooling of the TTL, which inhibits the diabatic ascent of moist air across isentropic surfaces to the stratosphere. Therefore, the radiative balance of the TTL under the impact of the cyclone does not favor the maintenance of moist anomalies in the TTL or transporting water vertically to the stratosphere.

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Impacts of tropical cyclones on the thermodynamic conditions in the tropical tropopause layer observed by A-train satellites

10.5194/acp-2021-154 ◽

2021 ◽

Author(s):

Jing Feng ◽

Yi Huang

Keyword(s):

Water Vapor ◽

Tropical Cyclones ◽

Distribution Patterns ◽

Radiative Heating ◽

Radiative Cooling ◽

Heating Rates ◽

Radiative Balance ◽

Tropical Tropopause Layer ◽

Tropical Tropopause ◽

The Impact

Abstract. The tropical tropopause layer (TTL) is the transition layer between the troposphere and the stratosphere. Tropical cyclones may impact the TTL by perturbing the vertical distributions of cloud, temperature, and water vapor, although this impact is poorly quantified due to the lack of collocated data. To address this problem, we implement a synergistic retrieval approach to obtain the thermodynamic profiles and ice water content above thick high-level clouds using the A-Train satellite measurements that pass over the tropical cyclones. This study detects the signature of cyclone impact on the distribution patterns of cloud, water vapor, temperature, and radiation by compositing these thermodynamic fields with respect to cyclone center locations. It is found that tropical cyclone events considerably increase the occurrence of TTL clouds, in the form of cirrus clouds above a clear troposphere. The amount of TTL cloud ice, however, is found to be mostly contributed by overshooting deep convections that penetrate the bottom of TTL. Using the synergistic retrieval method, we find a vertically oscillating pattern of temperature anomalies above tropical cyclones, with warming beneath the cloud top (around 16 km) and cooling above. The atmospheric column above 16 km is generally hydrated by overshooting convections, although dehydration is detected above non-overshooting TTL clouds. Above overshooting deep convections, the column-integrated water vapor is found to be on average 40 % higher than the climatology. Moreover, the TTL above tropical cyclones is cooled due to longwave radiative cooling. The radiative heating rates above cyclones are well differentiated by the brightness temperature of a satellite infrared channel in the window band. Using radiative calculations, it is found that TTL hydration is usually associated with radiative cooling of the TTL, which inhibits the diabatic ascent of moist air. The radiative balance of the TTL under the impact of the cyclone, therefore, is not in favor of maintaining the moist anomalies in the TTL or transporting water vertically to the stratosphere.

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A multi-sensor upper tropospheric ozone product (MUTOP) based on TES Ozone and GOES water vapor: derivation

Atmospheric Chemistry and Physics ◽

10.5194/acp-11-6515-2011 ◽

2011 ◽

Vol 11 (13) ◽

pp. 6515-6527 ◽

Cited By ~ 5

Author(s):

S. R. Felker ◽

J. L. Moody ◽

A. J. Wimmers ◽

G. Osterman ◽

K. Bowman

Keyword(s):

Water Vapor ◽

Potential Vorticity ◽

Tropospheric Ozone ◽

Forecast Model ◽

Scientific Basis ◽

Specific Humidity ◽

Water Vapor Absorption ◽

Upper Troposphere ◽

Weather Patterns ◽

Mixing Ratios

Abstract. The Tropospheric Emission Spectrometer (TES), a hyperspectral infrared instrument on the Aura satellite, retrieves a vertical profile of tropospheric ozone. However, polar-orbiting instruments like TES provide limited nadir-view coverage. This work illustrates the value of these observations when taken in context with geostationary imagery describing synoptic-scale weather patterns. The goal of this study is to create map-view products of upper troposphere (UT) ozone through the integration of TES ozone measurements with two synoptic dynamic tracers of stratospheric influence: specific humidity derived from the GOES Imager water vapor absorption channel, and potential vorticity (PV) from an operational forecast model. As a mixing zone between tropospheric and stratospheric reservoirs, the upper troposphere (UT) exhibits a complex chemical makeup. Determination of ozone mixing ratios in this layer is especially difficult without direct in situ measurement. However, it is well understood that UT ozone is correlated with dynamical tracers like low specific humidity and high potential vorticity. Blending the advantages of two remotely sensed quantities (GOES water vapor and TES ozone) is at the core of the Multi-sensor Upper Tropospheric Ozone Product (MUTOP). Our results suggest that 72 % of TES-observed UT ozone variability can be explained by its correlation with dry air and high PV. MUTOP reproduces TES retrievals across the GOES-West domain with a root mean square error (RMSE) of 18 ppbv (part per billion by volume). There are several advantages to this multi-sensor derived product approach: (1) it is calculated from two operational fields (GOES specific humidity and GFS PV), so maps of layer-average ozone can be created and used in near real-time; (2) the product provides the spatial resolution and coverage of a geostationary image as it depicts the variable distribution of ozone in the UT; and (3) the 6 h temporal resolution of the derived product imagery allows for the visualization of rapid movement of this dynamically-driven ozone, as illustrated in the animation Supplement. This paper presents the scientific basis and methodology behind the creation of this unique ozone product, as well as a statistical comparison of the derived product to an evaluation dataset of coincident TES observations.

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Water Vapor Retrievals from Spectral Direct Irradiance Measured with an EKO MS-711 Spectroradiometer—Intercomparison with Other Techniques

Remote Sensing ◽

10.3390/rs13030350 ◽

2021 ◽

Vol 13 (3) ◽

pp. 350

Author(s):

Rosa Delia García ◽

Emilio Cuevas ◽

Victoria Eugenia Cachorro ◽

Omaira E. García ◽

África Barreto ◽

...

Keyword(s):

Water Vapor ◽

Power Plants ◽

Precipitable Water ◽

Satellite System ◽

Infrared Spectrometry ◽

Radiative Balance ◽

Direct Normal Irradiance ◽

Routine Basis ◽

Solar Power Plants ◽

Global Navigation Satellite

Precipitable water vapor retrievals are of major importance for assessing and understanding atmospheric radiative balance and solar radiation resources. On that basis, this study presents the first PWV values measured with a novel EKO MS-711 grating spectroradiometer from direct normal irradiance in the spectral range between 930 and 960 nm at the Izaña Observatory (IZO, Spain) between April and December 2019. The expanded uncertainty of PWV (UPWV) was theoretically evaluated using the Monte-Carlo method, obtaining an averaged value of 0.37 ± 0.11 mm. The estimated uncertainty presents a clear dependence on PWV. For PWV ≤ 5 mm (62% of the data), the mean UPWV is 0.31 ± 0.07 mm, while for PWV > 5 mm (38% of the data) is 0.47 ± 0.08 mm. In addition, the EKO PWV retrievals were comprehensively compared against the PWV measurements from several reference techniques available at IZO, including meteorological radiosondes, Global Navigation Satellite System (GNSS), CIMEL-AERONET sun photometer and Fourier Transform Infrared spectrometry (FTIR). The EKO PWV values closely align with the above mentioned different techniques, providing a mean bias and standard deviation of −0.30 ± 0.89 mm, 0.02 ± 0.68 mm, −0.57 ± 0.68 mm, and 0.33 ± 0.59 mm, with respect to the RS92, GNSS, FTIR and CIMEL-AERONET, respectively. According to the theoretical analysis, MB decreases when comparing values for PWV > 5 mm, leading to a PWV MB between −0.45 mm (EKO vs. FTIR), and 0.11 mm (EKO vs. CIMEL-AERONET). These results confirm that the EKO MS-711 spectroradiometer is precise enough to provide reliable PWV data on a routine basis and, as a result, can complement existing ground-based PWV observations. The implementation of PWV measurements in a spectroradiometer increases the capabilities of these types of instruments to simultaneously obtain key parameters used in certain applications such as monitoring solar power plants performance.

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