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Train-Borne Measurements Of Tropical Methane Enhancements From Ephemeral Wetlands In Australia, Nicholas M. Deutscher, David W. T Griffith, Clare Paton-Walsh, Rittick Borah
Train-Borne Measurements Of Tropical Methane Enhancements From Ephemeral Wetlands In Australia, Nicholas M. Deutscher, David W. T Griffith, Clare Paton-Walsh, Rittick Borah
Faculty of Science - Papers (Archive)
We report greenhouse gas concentrations measured on a train covering a north-south transect through central Australia from north to south coast. During the monsoonal wet season we found significant enhancements in methane that correlate well with changing area of wetland inundation in Australian tropical savanna regions. We used a meteorological and air pollution model to quantify the ephemeral wetland fluxes necessary to cause the observed enhancements and estimate the constant Australian tropical wetland emissions. Annual Australian tropical ephemeral wetland fluxes are estimated at 0.4 +/- 0.2 Tg CH4, with permanent wetlands contributing a similar amount, 0.5 +/- 0.2 Tg CH4.
Estimated Total Emissions Of Trace Gases From The Canberra Wildfires Of 2003: A New Method Using Satellite Measurements Of Aerosol Optical Depth & The Mozart Chemical Transport Model, Clare Paton-Walsh, L Emmons, Stephen R. Wilson
Estimated Total Emissions Of Trace Gases From The Canberra Wildfires Of 2003: A New Method Using Satellite Measurements Of Aerosol Optical Depth & The Mozart Chemical Transport Model, Clare Paton-Walsh, L Emmons, Stephen R. Wilson
Faculty of Science - Papers (Archive)
In this paper we describe a new method for estimating trace gas emissions from large vegetation fires using satellite measurements of aerosol optical depth (AOD) at 550 nm, combined with an atmospheric chemical transport model. The method uses a threshold value to screen out normal levels of AOD that may be caused by raised dust, sea salt aerosols or diffuse smoke transported from distant fires. Using this method we infer an estimated total emission of 15±5 Tg of carbon monoxide, 0.05±0.02 Tg of hydrogen cyanide, 0.11±0.03 Tg of ammonia, 0.25±0.07 Tg of formaldehyde, 0.03±0.01 of acetylene, 0.10±0.03 Tg of ethylene, …
The Importance Of Transport Model Uncertainties For The Estimation Of Co2 Sources And Sinks Using Satellite Measurements, S Houweling, I Aben, F.-M Breon, F Chevallier, N Deutscher, R Engelen, C Gerbig, D Griffith, K Hungershoefer, R Macatangay, J Marshall, J Notholt, W Peters, S Serrar
The Importance Of Transport Model Uncertainties For The Estimation Of Co2 Sources And Sinks Using Satellite Measurements, S Houweling, I Aben, F.-M Breon, F Chevallier, N Deutscher, R Engelen, C Gerbig, D Griffith, K Hungershoefer, R Macatangay, J Marshall, J Notholt, W Peters, S Serrar
Faculty of Science - Papers (Archive)
This study presents a synthetic model intercomparison to investigate the importance of transport model errors for estimating the sources and sinks of CO2 using satellite measurements. The experiments were designed for testing the potential performance of the proposed CO2 lidar A-SCOPE, but also apply to other space borne missions that monitor total column CO2. The participating transport models IFS, LMDZ, TM3, and TM5 were run in forward and inverse mode using common CO2 fluxes and initial concentrations. Simulated column averaged CO2 (xCO 2) mixing ratios vary between the models by σCombining double low line0.5 ppm over the continents and σCombining …
Laboratory Measurements Of Trace Gas Emissions From Biomass Burning Of Fuel Types From The Southeastern And Southwestern United States, I R. Burling, R J. Yokelson, David W. Griffith, T J. Johnson, P Veres, J.M. Roberts, Carsten Warneke, S P. Urbanski, J Reardon, D R. Weise, W M Hao, Joost A. De Gouw
Laboratory Measurements Of Trace Gas Emissions From Biomass Burning Of Fuel Types From The Southeastern And Southwestern United States, I R. Burling, R J. Yokelson, David W. Griffith, T J. Johnson, P Veres, J.M. Roberts, Carsten Warneke, S P. Urbanski, J Reardon, D R. Weise, W M Hao, Joost A. De Gouw
Faculty of Science - Papers (Archive)
Vegetation commonly managed by prescribed burning was collected from five southeastern and southwestern US military bases and burned under controlled conditions at the US Forest Service Fire Sciences Laboratory in Missoula, Montana. The smoke emissions were measured with a large suite of state-of-the-art instrumentation including an open-path Fourier transform infrared (OP-FTIR) spectrometer for measurement of gas-phase species. The OP-FTIR detected and quantified 19 gas-phase species in these fires: CO2, CO, CH4, C2H2, C2H4, C3H6, HCHO, HCOOH, CH3OH, CH3COOH, furan, H2O, NO, NO2, HONO, NH3, HCN, HCl, and SO2. Emission factors for these species are presented for each vegetation type burned. …
Co-Located Column And In Situ Measurements Of Co2 In The Tropics Compared With Model Simulations, T Warneke, A K. Petersen, C Gerbig, A Jordan, C Rodenbeck, M Rothe, Ronald Macatangay, J Norholt, O Schrems
Co-Located Column And In Situ Measurements Of Co2 In The Tropics Compared With Model Simulations, T Warneke, A K. Petersen, C Gerbig, A Jordan, C Rodenbeck, M Rothe, Ronald Macatangay, J Norholt, O Schrems
Faculty of Science - Papers (Archive)
The first ground-based remote sensing measurements of the column averaged volume mixing ratio of CO2 (XCO2) in tropical South America have been obtained at Paramaribo, Suriname (5.8 N, 55.2 W). The remote sensing observations are complemented by surface air-samples collected at the site, analyzed for CO2 and 13CO2. The surface in-situ measurements are strongly influenced by local sources. From the isotopic composition of the air samples the local source component is suggested to be dominated by the terrestrial biosphere. Using 13C from the NOAA/ESRL stations Ascension Is. (ASC), 7.9 S, 14.4W, and Ragged Point (RPB), 13.2 N, 59.4W, the data …
Nanometer-Scale Distance Measurements In Proteins Using Gd3+ Spin Labeling, Alexey Potapov, Hiromasa Yagi, Thomas Huber, Slobodan Jergic, Nicholas E. Dixon, Gottfried Otting, Daniella Goldfarb
Nanometer-Scale Distance Measurements In Proteins Using Gd3+ Spin Labeling, Alexey Potapov, Hiromasa Yagi, Thomas Huber, Slobodan Jergic, Nicholas E. Dixon, Gottfried Otting, Daniella Goldfarb
Faculty of Science - Papers (Archive)
Methods for measuring nanometer-scale distances between specific sites in proteins are essential for analysis of their structure and function. In this work we introduce Gd3+ spin labeling for nanometer-range distance measurements in proteins by high-field pulse electron paramagnetic resonance (EPR). To evaluate the performance of such measurements, we carried out four-pulse double-electron electron resonance (DEER) measurements on two proteins, p75ICD and τC14, labeled at strategically selected sites with either two nitroxides or two Gd3+ spin labels. In analogy to conventional site-directed spin labeling using nitroxides, Gd3+ tags that are derivatives of dipicolinic acid were covalently attached to cysteine thiol groups. …
Validation Of Five Years (2003-2007) Of Sciamachy Co Total Column Measurements Using Ground-Based Spectrometer Observations, A T. J De Laat, A M. S Gloudemans, H Schrijver, I Aben, Y Nagahama, K Suzuki, E Mahieu, N B. Jones, Clare Paton-Walsh, N M. Deutscher, D W. T Griffith, M De Maziere, R L. Mittermeier, H Fast, J Notholt, M Palm, T Hawat, T Blumenstock, F Hase, M Schneider, C Rinsland, A V. Dzhola, E I. Grechko, A M. Poberovskii, M V. Makarova, J Mellqvist, A Strandberg, R Sussmann, T Borsdorff, M Rettinger
Validation Of Five Years (2003-2007) Of Sciamachy Co Total Column Measurements Using Ground-Based Spectrometer Observations, A T. J De Laat, A M. S Gloudemans, H Schrijver, I Aben, Y Nagahama, K Suzuki, E Mahieu, N B. Jones, Clare Paton-Walsh, N M. Deutscher, D W. T Griffith, M De Maziere, R L. Mittermeier, H Fast, J Notholt, M Palm, T Hawat, T Blumenstock, F Hase, M Schneider, C Rinsland, A V. Dzhola, E I. Grechko, A M. Poberovskii, M V. Makarova, J Mellqvist, A Strandberg, R Sussmann, T Borsdorff, M Rettinger
Faculty of Science - Papers (Archive)
Abstract. This paper presents a validation study of SCanning Imaging Absorption spectroMeter for Atmospheric CHartographY (SCIAMACHY) carbon monoxide (CO) total column measurements from the Iterative Maximum Likelihood Method (IMLM) algorithm using ground-based spectrometer observations from twenty surface stations for the five year time period of 2003–2007. Overall we find a good agreement between SCIAMACHY and ground-based observations for both mean values as well as seasonal variations. For high-latitude Northern Hemisphere stations absolute differences between SCIAMACHY and ground-based measurements are close to or fall within the SCIAMACHY CO 2 precision of 0.2×1018 molecules/cm2 (10%) indicating that SCIAMACHY can observe CO accurately …