Maryland Shared Open Access Repository

MD-SOAR is a shared digital repository platform for twelve colleges and universities in Maryland. It is currently funded by the University System of Maryland and Affiliated Institutions (USMAI) Library Consortium (usmai.org) and other participating partner institutions. MD-SOAR is jointly governed by all participating libraries, who have agreed to share policies and practices that are necessary and appropriate for the shared platform. Within this broad framework, each library provides customized repository services and collections that meet local institutional needs. Please follow the links below to learn more about each library's repository services and collections.

 

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Oltmans Receives 2013 Yoram J. Kaufman Unselfish Cooperation in Research Award
(AGU, 2014-08-26) Thompson, Anne M.
Samuel “Sam” Oltmans, an AGU Fellow since 2007, was head of the National Oceanic and Atmospheric Administration's (NOAA) Global Monitoring Division Ozone and Water Vapor group for more than 30 years. He is currently a senior research scientist at the Cooperative Institute for Research in the Environmental Sciences (CIRES) of the University of Colorado at Boulder.
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Stratospheric ozone trends and variability as seen by SCIAMACHY from 2002 to 2012
(EGU, 2014-01-24) Gebhardt, C.; Rozanov, A.; Hommel, R.; Weber, M.; Bovensmann, H.; Burrows, J. P.; Degenstein, D.; Froidevaux, L.; Thompson, Anne M.
Vertical profiles of the rate of linear change (trend) in the altitude range 15–50 km are determined from decadal O₃ time series obtained from SCIAMACHY¹/ENVISAT² measurements in limb-viewing geometry. The trends are calculated by using a multivariate linear regression. Seasonal variations, the quasi-biennial oscillation, signatures of the solar cycle and the El Niño–Southern Oscillation are accounted for in the regression. The time range of trend calculation is August 2002–April 2012. A focus for analysis are the zonal bands of 20° N–20° S (tropics), 60–50° N, and 50–60° S (midlatitudes). In the tropics, positive trends of up to 5% per decade between 20 and 30 km and negative trends of up to 10% per decade between 30 and 38 km are identified. Positive O₃ trends of around 5% per decade are found in the upper stratosphere in the tropics and at midlatitudes. Comparisons between SCIAMACHY and EOS MLS³ show reasonable agreement both in the tropics and at midlatitudes for most altitudes. In the tropics, measurements from OSIRIS4/Odin and SHADOZ⁵ are also analysed. These yield rates of linear change of O₃ similar to those from SCIAMACHY. However, the trends from SCIAMACHY near 34 km in the tropics are larger than MLS and OSIRIS by a factor of around two. ¹ SCanning Imaging Absorption spectroMeter for Atmospheric CHartographY ² European environmental research satellite ³ Earth Observing System (EOS) Microwave Limb Sounder (MLS) ⁴ Optical Spectrograph and InfraRed Imager System ⁵ Southern Hemisphere ADditional OZonesondes
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Comparison of Tropical Ozone from SHADOZ with Remote Sensing Retrievals from Suomi-npp Ozone Mapping Profile Suite (OMPS)
(2014-09-22) Witte, Jacquelyn C.; Thompson, Anne M.; Ziemke, Jerald R.; Wargan, Krzysztof
The Ozone Mapping Profile Suite (OMPS) was launched October 28, 2011 on-board the Suomi NPP satellite (http://npp.gsfc.nasa.gov). OMPS is the next generation total column ozone mapping instrument for monitoring the global distribution of stratospheric ozone. OMPS includes a limb profiler to measure the vertical structure of stratosphere ozone down to the mid-troposphere. This study uses tropical ozonesonde profile measurements from the Southern Hemisphere Additional Ozonesondes (SHADOZ, http://croc.gsfc.nasa.gov/shadoz) archive to evaluate total column ozone retrievals from OMPS and concurrent measurements from the Aura Ozone Monitoring Instrument (OMI), the predecessor of OMPS with a data record going back to 2004. We include ten SHADOZ stations that contain data overlapping the OMPS time period (2012-2013). This study capitalizes on the ozone profile measurements from SHADOZ to evaluate OMPS limb profile retrievals. Finally, we use SHADOZ sondes and OMPS retrievals to examine the agreement with the GEOS-5 Ozone Assimilation System (GOAS). The GOAS uses data from the OMI and the Microwave Limb Sounder (MLS) to constrain the total column and stratospheric profiles of ozone. The most recent version of the assimilation system is well constrained to the total column compared with SHADOZ ozonesonde data.
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On the hiatus in the acceleration of tropical upwelling since the beginning of the 21st century
(EGU, 2014-12-05) Aschmann, J.; Burrows, J. P.; Gebhardt, C.; Rozanov, A.; Hommel, R.; Weber, M.; Thompson, Anne M.
Chemistry–climate models predict an acceleration of the upwelling branch of the Brewer–Dobson circulation as a consequence of increasing global surface temperatures, resulting from elevated levels of atmospheric greenhouse gases. The observed decrease of ozone in the tropical lower stratosphere during the last decades of the 20th century is consistent with the anticipated acceleration of upwelling. However, more recent satellite observations of ozone reveal that this decrease has unexpectedly stopped in the first decade of the 21st century, challenging the implicit assumption of a continuous acceleration of tropical upwelling. In this study we use three decades of chemistry-transport-model simulations (1980–2013) to investigate this phenomenon and resolve this apparent contradiction. Aside from a high-bias between 1985–1990, our model is able to reproduce the observed tropical lower stratosphere ozone record. A regression analysis identifies a significant decrease in the early period followed by a statistically robust trend-change after 2002, in qualitative agreement with the observations. We demonstrate that this trend-change is correlated with structural changes in the vertical transport, represented in the model by diabatic heating rates taken from the reanalysis product Era-Interim. These changes lead to a hiatus in the acceleration of tropical upwelling between 70–30 hPa and a southward shift of the tropical pipe at 30 and 100 hPa during the past decade, which appear to be the primary causes for the observed trend-change in ozone.
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Bollasina Receives 2013 James R. Holton Junior Scientist Award
(AGU, 2014-08-26) Thompson, Anne M.
Dr. Massimo Bollasina, a postdoctoral scholar at the National Oceanic and Atmospheric Administration's (NOAA) Geophysical Fluid Dynamics Lab (GFDL) through the Princeton University Atmospheric and Ocean Science Visitors Program, is this year's recipient of the James R. Holton Junior Scientist Award from AGU's Atmospheric Sciences section, named after a pioneer in atmospheric dynamics, the late James R. Holton of the University of Washington. Since its inception in 2004, the Holton Award has become a highly sought honor. It recognizes the achievements and potential of a junior AGU member whose Ph.D. was awarded within 3 years of the nomination deadline.