We present measurements of stratospheric water vapor and aerosols in the Antarctic from the POAM III instrument during the period April through December 1998. The measured variations in water vapor enable us to study both descent in the vortex and the effect of dehydration that occurs in the lower stratosphere below ∼23 km when the temperature drops below the frost point in July. There is a temporal correlation between the dehydration that occurs in July and an increase in high aerosol optical depth events in the lower stratosphere, suggesting that these events are due to the presence of ice PSC's. When temperatures warm up there is some rehydration at the highest altitudes of the dehydrated region (∼20–23 km), probably resulting from descent within the vortex. At ∼12 km rehydration is probably the result of mixing in of air from outside the vortex. The temperature increase in October produces little rehydration at 17 km and no clear rehydration at 14 km, suggesting that the water has precipitated out of these layers.
Polar Ozone and Aerosol Measurement (POAM) III, a follow-on to the successful POAM II, is a spaceborne experiment designed to measure the vertical profiles of ozone, water vapor, nitrogen dioxide, and aerosol extinction in the polar stratosphere and upper troposphere with a vertical resolution of 1–2 km. Measurements are made by the solar occultation technique. POAM III, now in polar orbit aboard the SPOT 4 satellite, is providing data on north- and south-polar ozone phenomena, including the south-polar ozone hole, and on the spatial and temporal variability of stratospheric aerosols, polar stratospheric clouds, and polar mesospheric clouds. Differences between the POAM III and POAM II instruments are described. First validations of POAM III data products by comparison with Halogen Occultation Experiment and ozonesonde data are presented.
This paper discusses the validation of measurements of O3 distribution in the Earth's atmosphere made by the Millimeter‐wave Atmospheric Sounder (MAS), a component of NASA's ATLAS spacelab shuttle package. Measurements of 184 GHz O3 emission from the Earth's limb at tangent altitudes between 20 and 80 km were made with a 50 channel radiometer having a spectral resolution of 200 KHz. In three missions the emissions of O3, H2O, ClO, and O2 were measured between 70°S and 70°N latitudes. O3 mixing ratio calculations and error analysis were performed with the Rodgers optimal estimation method. Data binned in 128 s batches yield mixing ratio profiles with an altitude resolution of 7 km at the O3 peak and an estimated accuracy of 5%. Additional retrievals made with all data from each mission binned in 5° latitude zones yield mixing ratios with about 5 km altitude resolution and somewhat improved accuracy. Comparisons with coincident measurements from other space platforms indicate a general agreement within approximately 5%. The data are publicly available through the German Remote Sensing Data Center.
Ozone profile measurements were made by three instruments, ATMOS, MAS, and SSBUV, using distinctly different observing techniques, as part of the ATLAS Space Shuttle missions in March 1992, April 1993, and November 1994. ATMOS makes solar-occultation observations of infrared spectra using a Fourier transform interferometer. MAS uses a limb-scanning antenna to measure emission spectra at millimeter wavelengths. SSBUV is a nadir-viewing instrument measuring the transmission of scattered solar ultraviolet radiation modified by ozone absorption. A sample of zonal-mean mixing ratio profiles indicates that these three ATLAS instruments generally agree to within 10%, although a few potential biases have been noted. There are significant differences in the character of the agreement between ATLAS 1 and ATLAS 2 which will require further study.
We present measurements of the latitudinal variation of nighttime O3 and H2O in the mesosphere and (for O3) lower thermosphere obtained with the Millimeter‐wave Atmospheric Sounder (MAS) instrument during the ATLAS 2 mission (8–15 April 1993). These are the first such measurements that have ever been reported. They indicate an O3 mixing ratio minimum at mid‐latitudes in the upper mesosphere, with maxima in the tropics and at high latitudes. The H2O retrievals indicate H2O mixing ratios decreasing toward the poles in both hemispheres in the upper mesosphere. We also present measurements of the diurnal variation of O3 at southern mid‐latitudes, at higher vertical resolution than has ever been reported previously. The results are generally consistent with previous measurements and modeling studies.
MAS (Millimeter‐wave Atmospheric Sounder) observations from the shuttle ATLAS spacelab pallet have revealed some little known (and unexplained) structure in stratospheric ozone mixing ratio profiles at sub‐polar latitudes, of both hemispheres. Qualitatively similar features are observed by UARS instruments. Another possibly related feature has been observed by ground‐based remote sensing from the South Pole over an extended season. In all these cases, it seems likely that active photochemistry and highly structured horizontal and vertical transport play important roles. Some evidence of a similar feature is also present in a current 2‐D photochemical model. This high latitude phenomenon is both an intriguing challenge for current 3‐D models and potentially useful test for validating remote sensing experiments.
The Millimeter-Wave Atmospheric Sounder (MAS) is a shuttle-based limb-sounding instrument designed for global spectroscopic studies of O-3, and constituents important in O-3 photochemistry, in the middle atmosphere. It is part of the NASA's Atmospheric Laboratory for Applications and Science (ATLAS) spacelab shuttle mission. This paper presents an overview of the instrument, operation, and data analysis. In addition, as an example of the results, we present zonal average retrievals for O-3, H2O, and ClO obtained in ATLAS 1. The MAS O-3 and H2O measurements are shown to agree well with simultaneous observations made with the UARS MLS instrument.
We report on stratospheric and mesospheric water vapor (H2O) observations obtained by the Millimeter wave Atmospheric Sounder (MAS) in the Arctic spring of 1992. In the lower stratosphere, the observations show enhanced H2O inside the vortex between 450 K and 625 K, in agreement with other H2O observations. In the upper stratosphere and lower mesosphere, at potential temperatures between 1850 K and 2200 K, we find regions of depressed H2O volume mixing ratio coincident with remnants of high potential vorticity. The depressed mesospheric H2O, as well as the enhanced lower stratospheric H2O, are consistent with wintertime descent. It also suggests effective containment of air up into the lower mesosphere.
β-Blockers (BBs) are a widely used class of medications with a number of medical indications. Their ability to suppress the adrenergic response has made them a target of investigation for treating a variety of psychiatric symptoms.The aim of this review is to identify evidence regarding the use of BBs for various psychiatric disorders including anxiety disorders, mood disorders, psychosis, and posttraumatic stress disorder. We also review the evidence for use for aggression and agitation and for extrapyramidal side effects of psychiatric medications.A search of PubMed and Google Scholar was conducted with search terms relevant to the use of BBs for psychiatric conditions. Studies were selected based on relevance to the review objective, focusing on systematic reviews and meta-analyses. Case reports were included and are clearly identified when referenced in this review.A total of 44 publications were included that examined the use of BBs as treatment for the following psychiatric symptoms and conditions: anxiety disorders, depression and mood disorders, acute stress disorder and postraumatic stress disorder, psychotic disorders and extrapyramidal symptoms, as well as aggression and agitation. Additionally, adverse effects and drug-drug interactions were reviewed.Well-characterized psychiatric uses of BBs include treating symptoms of performance anxiety and akathisia. Some positive evidence exists for BB therapy in other disorders such as specific phobia, panic disorder, and for aggression in patients with psychosis, acquired brain injury, or intellectual disability. Most of the evidence on the role of BBs in psychiatry is as adjunctive treatment for management of somatic symptoms rather than as monotherapy. Outside of performance anxiety and akathisia, the role of BBs in psychiatry has not been subjected to careful study, and further investigative trials are needed.