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GPS radio occultations captured by receivers on board the CHAMP and SAC-C spacecraft were used to study the evolution of temperature profiles in the Arctic region north of 65 degrees.
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Stratospheric hydration and dehydration were measured inside the Arctic polar vortex in January and February 2000, as part of the Sage III Ozone Loss Validation Experiment (SOLVE).
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During the January 2000 deployment of the SAGE III Ozone Loss Validation Experiment (SOLVE), the NASA ER-2 aircraft intercepted air parcels with unusual water mixing ratios within the the Arctic polar vortex.
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In the boreal forest region and for coniferous forest species, the summer frost free period bounds the growing season length (Walter et Breckle 1993). For both coniferous and deciduous trees, their grown potential is further limited by their mineral and water uptake.
High altitude balloon flights of a combined payload of the Submillimeterwave Limb Sounder and the whole air sampler instruments were performed on 27 January 1995 and 08 March 1995. Both flights were launched from sweden as part of the Second European Stratospheric Arctic and Mid-latitude Experiment (SESAME). Results of the first flight suggest that most of the available chlorine had been converted to CLOx in the observed air parcel, while warmer air in the second flight had much more HCl than CLOx.
Instruments on board the Upper Atmosphere Research Satellite have been measuring stratospheric temperatures, winds, and constituent species since September 1991. Among the correlative data that aid in interpreting this data are two sets of global meteorological analyses. Meteorological data from the United Kingdom Meteorological Office (UKMO), and the US National Meteorological Center (NMC) are discussed.
Microwave Limb Sounder observations of mid-stratospheric ozone during stratospheric warmings show tongues of high ozone drawn up from low latitudes into the developing anticyclone.
Concentrations of HC1 measured in the 1991/3 northern hemisphere lower stratosphere from the ER-2 aircraft are significantly lower than model predictions using both gas phase and heterogeneous chemistry, but are in much better agreement with model predictions for the 1994 southern hemisphere.
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The tidal signature in the middle atmospheric thermal structure is investigated using more than 140 hours of nighttime lidar measurements at Table Mountain (34.4 degrees north) during January 1997 and February 1998.
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We synthesize daily sonde (vertical) information and daily satellite (horizontal) information to provide an empirical description of ozone origins over the northern Indian Ocean during the INDOEX (Indian Ocean Experiment) field campaign (February-March 1999). This area is shown to be a significant portion of the "high-ozone tropics". East-west O3 features and their flow are identified, and ozone origins are compared to other tropical regions, using water vapor as a second tracer. In the study period, multiple processes contribute to O3 column enhancements, their importance varying strongly by latitude: (1) Low-altitude O3 pollution over the northern Indian Ocean mainly originates from the Indian subcontinent and is traceable to high emission areas. Convective activity south of Sri Lanka helps direct ozone outflow from the northern Indian subcontinent. (2) Middle tropospheric O3 maxima over the northern Indian Ocean originate from various sources, often transitioning within a few hours. Convective venting of Asian pollutants can add 20-30 ppbv to the middle troposphere at 5degN-10degN, alternating with stratospheric influence. (3) A number of cases suggest that strong mixing-in of stratospheric air along the subtropical jet raised tropospheric O3 in early March by approx.40-50 ppbv, especially poleward of approx. 10degN. (4) Influences of lightning and large-scale biomass burning were not strong during this period, in contrast to the situation in Africa and the South Atlantic or locally in Southeast Asia. This work illustrates successes and limitations in approaches to synthesizing disparate information on trace-gas distributions taken from satellite retrieval products and ozonesondes.