Open Access. Powered by Scholars. Published by Universities.®
Physical Sciences and Mathematics Commons™
Open Access. Powered by Scholars. Published by Universities.®
U.S. - Japan Bilateral Workshop on the Tropical Tropopause Layer: State of the Current Science and Future Observational Needs
- File Type
Articles 1 - 30 of 53
Full-Text Articles in Physical Sciences and Mathematics
Campaign Logistics, Mapping, And Discussion (Climate), Student Group
Campaign Logistics, Mapping, And Discussion (Climate), Student Group
U.S. - Japan Bilateral Workshop on the Tropical Tropopause Layer: State of the Current Science and Future Observational Needs
No abstract provided.
Campaign Logistics, Mapping, And Discussion (Djf), Student Group
Campaign Logistics, Mapping, And Discussion (Djf), Student Group
U.S. - Japan Bilateral Workshop on the Tropical Tropopause Layer: State of the Current Science and Future Observational Needs
No abstract provided.
Campaign Logistics, Mapping, And Discussion (Jja), Student Group
Campaign Logistics, Mapping, And Discussion (Jja), Student Group
U.S. - Japan Bilateral Workshop on the Tropical Tropopause Layer: State of the Current Science and Future Observational Needs
No abstract provided.
Summary And Discussion Of Science Questions (Climate), Student Group
Summary And Discussion Of Science Questions (Climate), Student Group
U.S. - Japan Bilateral Workshop on the Tropical Tropopause Layer: State of the Current Science and Future Observational Needs
No abstract provided.
Summary And Discussion Of Science Questions (Djf), Student Group
Summary And Discussion Of Science Questions (Djf), Student Group
U.S. - Japan Bilateral Workshop on the Tropical Tropopause Layer: State of the Current Science and Future Observational Needs
No abstract provided.
Summary And Discussion Of Science Questions (Jja), Student Group
Summary And Discussion Of Science Questions (Jja), Student Group
U.S. - Japan Bilateral Workshop on the Tropical Tropopause Layer: State of the Current Science and Future Observational Needs
No abstract provided.
Identification Of Ttl Boundaries Using The Ozone-Water Vapor Relationship, Laura Pan
Identification Of Ttl Boundaries Using The Ozone-Water Vapor Relationship, Laura Pan
U.S. - Japan Bilateral Workshop on the Tropical Tropopause Layer: State of the Current Science and Future Observational Needs
Two sets of TTL boundary definitions have been proposed in the literature. One uses the static stability structure (Gettelman and Foster, 2002) and the other uses the radiative forcing mass flux criterion (Fu et al., 2007; Fueglistaler et al., 2009). In this work, we present a method to characterize the TTL boundaries using ozone–water vapor relationship. The result shows that the tracer behavior supports the level of the minimum stability to be the lower boundary of the transition layer and the cold point to be a good proxy of the upper boundary. Using this method, we characterize and compare the …
Ozone Variations Over The Northern Subtropical Region Revealed By Ozonesonde Observations In Hanoi, Shin-Ya Ogino
Ozone Variations Over The Northern Subtropical Region Revealed By Ozonesonde Observations In Hanoi, Shin-Ya Ogino
U.S. - Japan Bilateral Workshop on the Tropical Tropopause Layer: State of the Current Science and Future Observational Needs
Seasonal and subseasonal variations in the ozone mixing ratio (OMR) are investigated by using continuous seven-year ozonesonde data from Hanoi (21 0 N, 106 0 E), Vietnam. The mean seasonal variations for the seven years show large amplitude at the upper troposphere and lower stratosphere (UTLS) region (10–18 km) and at the lower troposphere (around 3 km) with standard deviations relative to the mean value of about 30% for both regions. In the UTLS region, the seasonal variation in the OMR shows a minimum in winter and a maximum in spring to summer. The variation seems to be caused by …
The Noaa H2o And O3 Data Base, Karen Rosenlof
The Noaa H2o And O3 Data Base, Karen Rosenlof
U.S. - Japan Bilateral Workshop on the Tropical Tropopause Layer: State of the Current Science and Future Observational Needs
No abstract provided.
In-Situ Water Vapor And Ozone Measurements In Lhasa And Kunming During The Asian Summer Monsoon, Jianchun Bian, Laura L. Pan, Laura Paulik, Holger Vömel, Hongbin Chen, Daren Lu
In-Situ Water Vapor And Ozone Measurements In Lhasa And Kunming During The Asian Summer Monsoon, Jianchun Bian, Laura L. Pan, Laura Paulik, Holger Vömel, Hongbin Chen, Daren Lu
U.S. - Japan Bilateral Workshop on the Tropical Tropopause Layer: State of the Current Science and Future Observational Needs
Asian summer monsoon (ASM) anticyclone circulation is recognized to be a significant transport pathway for water vapor and pollutants to enter the stratosphere. Observational evidence, however, is largely based on satellite retrievals. We report the first coincident in situ measurements of water vapor and ozone within the ASM anticyclone. The combined water vapor and ozone sondes were launched from Kunming in August 2009 and Lhasa in August 2010. We present the key characteristics of these measurements, and provide a comparison to similar measurements from Alajuela, Costa Rica, an equatorial location, during the Tropical Composition, Cloud and Climate Coupling (TC4) campaign …
Development Of New Hydorometer Video Sonde (Hyvis) System For Ice Cloud Observation In Ttl Region, Kensaku Shimizu
Development Of New Hydorometer Video Sonde (Hyvis) System For Ice Cloud Observation In Ttl Region, Kensaku Shimizu
U.S. - Japan Bilateral Workshop on the Tropical Tropopause Layer: State of the Current Science and Future Observational Needs
Cirrus clouds in the TTL play an important role on the radiation budget and thus the understanding of their optical properties together with the microphysical processes associated with their formation is quite important. In spite of the progress in theoretical research on the TTL cirrus (e.g., Koop et al., 2000; Peter et al., 2006), observational research is not enough because of the difficulty due to its height and coldness. On the other hand, research of cirrus clouds at 10 km height has been carried out since 1990s using aircraft and hydrometer sondes such as HYVIS (Murakami and Orikasa, 1997) and …
Impact Of Abrupt Stratospheric Dynamical Change On Tropical Tropopause Layer, Nawo Eguchi, Kunihiko Kodera, Tomoe Nasuno
Impact Of Abrupt Stratospheric Dynamical Change On Tropical Tropopause Layer, Nawo Eguchi, Kunihiko Kodera, Tomoe Nasuno
U.S. - Japan Bilateral Workshop on the Tropical Tropopause Layer: State of the Current Science and Future Observational Needs
We have studied the impact of stratospheric circulation change on water vapor in the Tropical Tropopause Layer (TTL) during the stratospheric sudden warming (SSW) events (e.g., Eguchi and Kodera, 2010). Increased Brewer-Dobson circulation associated with SSW produces cooling in the tropical lower stratosphere (LS). The cooling generally produces more cirrus clouds and decreases of the water vapor mixing ratio (WV) in the TTL, except for some regions over Africa and South American continents where penetrating clouds are expected. This time, we found a new stratospheric phenomenon which produces abrupt warming in the tropical stratosphere converse to the SSW event. The …
Volatility And Composition Of Ttl Aerosols By Balloon-Borne In-Situ Observation, Masahiko Hayashi
Volatility And Composition Of Ttl Aerosols By Balloon-Borne In-Situ Observation, Masahiko Hayashi
U.S. - Japan Bilateral Workshop on the Tropical Tropopause Layer: State of the Current Science and Future Observational Needs
Tandem optical particle counters (OPC) were launched by balloon, from Biak 1 0 S, 136 0 E in January 2011 and 2012. One of the tandem OPC directly observed size distribution of aerosols of 0.3 – 7 µm in diameter, and another one observed size distributions in heated conditions of 100 0 , 150 0 , and 200 0 C through thermodenuder, to observe volatility of TTL aerosols. Most of TTL aerosol smaller than 0.8 µm in diameter show high volatility, suggesting to be composed of sulfuric acid or sulfate. There also exist non-volatile particles larger than 0.8 µm in …
Cloud-Top Height Dataset By Geostationary Satellite Split Window Measurements Trained With Cloudsat Data, Noriyuki Nishi
Cloud-Top Height Dataset By Geostationary Satellite Split Window Measurements Trained With Cloudsat Data, Noriyuki Nishi
U.S. - Japan Bilateral Workshop on the Tropical Tropopause Layer: State of the Current Science and Future Observational Needs
Lookup tables for estimating the cloud-top height (CTOP) and visible optical thickness of uppertropospheric clouds by the infrared brightness temperature (TB) at 10.8 μm (T11) and its difference from TB at 12 μm (DT11-12) measured by geostationary satellites are developed (Hamada and Nishi 2010, JAMC). These lookup tables were constructed by regressing the cloud radar measurements by the CloudSat satellite over the infrared measurements by the Japanese geostationary multifunctional transport satellite MTSAT-1R and MTSAT-2. The CTOP is available at http://database.rish.kyoto-u.ac.jp/arch/ctop/ since July 2005. The data have good precision for cirrus clouds (τ > ~3) that have large DT11-12 values and are …
Quantifying The Deep Convective Temperature Signal Within The Tropical Tropopause Layer (Ttl), Thomas Birner
Quantifying The Deep Convective Temperature Signal Within The Tropical Tropopause Layer (Ttl), Thomas Birner
U.S. - Japan Bilateral Workshop on the Tropical Tropopause Layer: State of the Current Science and Future Observational Needs
Dynamics on a vast range of spatial and temporal scales, from individual convective plumes to planetary-scale circulations, play a role in driving the temperature variability in the tropical tropopause layer (TTL). Here, we aim to better quantify the deep convective temperature signal within the TTL using multiple datasets. First, we investigate the link between ozone and temperature in the TTL using the Southern Hemisphere Additional Ozonesondes (SHADOZ) dataset. Low ozone concentrations in the TTL are indicative of deep convective transport from the boundary layer. We confirm the usefulness of ozone as an indicator of deep convection by identifying a typical …
Future Project Foci: Aeroclim, Markus Rex
Future Project Foci: Aeroclim, Markus Rex
U.S. - Japan Bilateral Workshop on the Tropical Tropopause Layer: State of the Current Science and Future Observational Needs
No abstract provided.
Future Project Foci: Contrast, Laura Pan
Future Project Foci: Contrast, Laura Pan
U.S. - Japan Bilateral Workshop on the Tropical Tropopause Layer: State of the Current Science and Future Observational Needs
No abstract provided.
Future Project Foci: Cast-Sonde, Geraint Vaughan
Future Project Foci: Cast-Sonde, Geraint Vaughan
U.S. - Japan Bilateral Workshop on the Tropical Tropopause Layer: State of the Current Science and Future Observational Needs
No abstract provided.
Future Project Foci: Battrex, Joan Alexander
Future Project Foci: Battrex, Joan Alexander
U.S. - Japan Bilateral Workshop on the Tropical Tropopause Layer: State of the Current Science and Future Observational Needs
No abstract provided.
Future Project Foci: Attrex, Eric Jensen
Future Project Foci: Attrex, Eric Jensen
U.S. - Japan Bilateral Workshop on the Tropical Tropopause Layer: State of the Current Science and Future Observational Needs
No abstract provided.
Ongoing Project Foci: Sower, Fumio Hasebe
Ongoing Project Foci: Sower, Fumio Hasebe
U.S. - Japan Bilateral Workshop on the Tropical Tropopause Layer: State of the Current Science and Future Observational Needs
No abstract provided.
Ongoing Project Foci: Shadoz, Anne Thompson
Ongoing Project Foci: Shadoz, Anne Thompson
U.S. - Japan Bilateral Workshop on the Tropical Tropopause Layer: State of the Current Science and Future Observational Needs
No abstract provided.
Ongoing Project Foci: Ticosonde, Henry Selkirk
Ongoing Project Foci: Ticosonde, Henry Selkirk
U.S. - Japan Bilateral Workshop on the Tropical Tropopause Layer: State of the Current Science and Future Observational Needs
No abstract provided.
Ongoing Project Foci: National Weather Service (Nws) Pacific Region Activities, Bill Ward
Ongoing Project Foci: National Weather Service (Nws) Pacific Region Activities, Bill Ward
U.S. - Japan Bilateral Workshop on the Tropical Tropopause Layer: State of the Current Science and Future Observational Needs
No abstract provided.
Ongoing Project Foci: Noaa, Dale Hurst
Ongoing Project Foci: Noaa, Dale Hurst
U.S. - Japan Bilateral Workshop on the Tropical Tropopause Layer: State of the Current Science and Future Observational Needs
No abstract provided.
Ongoing Project Foci: Gruan, Holger Vömel
Ongoing Project Foci: Gruan, Holger Vömel
U.S. - Japan Bilateral Workshop on the Tropical Tropopause Layer: State of the Current Science and Future Observational Needs
No abstract provided.
Correlated Variability Of Upwelling And Tracers Near The Tropical Tropopause, Marta Abalos
Correlated Variability Of Upwelling And Tracers Near The Tropical Tropopause, Marta Abalos
U.S. - Japan Bilateral Workshop on the Tropical Tropopause Layer: State of the Current Science and Future Observational Needs
Tropical upwelling should exert strong influence on temperatures and on tracers with large vertical gradients in the lower stratosphere. We test this behavior by comparing three upwelling estimates calculated from ERA‐Interim reanalysis data with observed temperatures in the tropical lower stratosphere, and with measurements of ozone and carbon monoxide (CO) from the Aura Microwave Limb Sounder (MLS) satellite instrument. Time series of temperature, ozone and CO are well correlated in the tropical lower stratosphere, and we quantify the influence of tropical upwelling on this joint variability. Strong coherent annual cycles observed in each quantity are found to reflect the seasonal …
Comparison Between Microphysical Model Simulation And Observed Cirrus Clouds Formation Within A Volcanic Aerosol Layer In The Tropical Tropopause Layer, Mayuko Sakurai
U.S. - Japan Bilateral Workshop on the Tropical Tropopause Layer: State of the Current Science and Future Observational Needs
In order to know the formation process of cirrus clouds in tropical tropopause layer, we used a microphysical numerical model to calculate nucleation and growing process of cirrus cloud particles, and compared the results of the model simulations with observed results. The observations compared had been performed at Biak, Indonesia in January 2011. Formation of cirrus clouds was observed by lidar in an aerosol layer at the altitude from 17.5 to 19 km. The backscatter coefficient of cirrus clouds was 10-8~10-7/m/str and number concentration was estimated less than 105/m3. Calculated results by …
Dehydration In The Ttl Estimated From The Water Vapor Match, Yoichi Inai
Dehydration In The Ttl Estimated From The Water Vapor Match, Yoichi Inai
U.S. - Japan Bilateral Workshop on the Tropical Tropopause Layer: State of the Current Science and Future Observational Needs
The match method is applied to the quantification of the dehydration process in the tropical tropopause layer (TTL) over the western Pacific. The match pairs are sought from the Soundings of Ozone and Water in the Equatorial Region (SOWER) campaign network observations with the use of isentropic trajectories. For those pairs identified, extensive screening procedures are performed to verify the representativeness of the air parcel and the validity of the isentropic treatment and to check possible water injection by deep convection, consistency between the sonde data and analysis field, and conservation of the ozone content. Among those pairs remaining, we …
Development Of A Balloon-Born Peltier-Based Chilled-Mirror Hygrometer For The Troposphere And The Lower Stratosphere, Takuji Sugidachi
Development Of A Balloon-Born Peltier-Based Chilled-Mirror Hygrometer For The Troposphere And The Lower Stratosphere, Takuji Sugidachi
U.S. - Japan Bilateral Workshop on the Tropical Tropopause Layer: State of the Current Science and Future Observational Needs
We have developed a new balloon-borne hygrometer, which is based on a chilled-mirror principle and uses a two stage Peltier cooler. In January 2012, we have conducted flight tests at Biak, Indonesia (1.180S, 136.110E) to evaluate the performances of this sensor. The result showed that this hygrometer has the ability to measure atmospheric water vapor from the surface to the lower stratosphere. It is considered that our hygrometer is helpful for TTL observation campaigns because of its ease-in-handling.