GMD Publications for 2013
Click on page icon to view abstract.
Andrews, A. E., J. Kofler, M. Trudeau, J. C. Williams, D. Neff, K. A. Masarie, D. Y. Chao, D. Kitzis, P. C. Novelli, C. L. Zhao, E. J. Dlugokencky, P. M. Lang, M. J. Crotwell, M. L. Fischer, M. J. Parker, J. T. Lee, D. D. Baumann, A. R. Desai, C. O. Stanier, S. F. J. de Wekker, D. E. Wolfe, J. W. Munger and P. P. Tans, (2013), CO2, CO and CH4 measurements from the NOAA Earth System Research Laboratory, Atmospheric Measurement Techniques Discussions, 6, 1, , 10.5194/amtd-6-1461-2013
Asaf, David, Eyal Rotenberg, Fyodor Tatarinov, Uri Dicken, Stephen A. Montzka and Dan Yakir, (2013), Ecosystem photosynthesis inferred from measurements of carbonyl sulphide flux, Nature Geoscience, , , 10.1038/ngeo1730
AbstractLimited understanding of carbon dioxide sinks and sources on land is often linked to the inability to distinguish between the carbon dioxide taken up by photosynthesis, and that released by respiration1, 2. Carbonyl sulphide, a sulphur-containing analogue of carbon dioxide, is also taken up by plants, and could potentially serve as a powerful proxy for photosynthetic carbon dioxide uptake, which cannot be directly measured above the leaf scale. Indeed, variations in atmospheric concentrations of carbonyl sulphide are closely related to those of carbon dioxide at regional, local and leaf scales3, 4, 5, 6, 7, 8, 9. Here, we use eddy covariance and laser spectroscopy10 to estimate the net exchange of carbon dioxide and carbonyl sulphide across three pine forests, a cotton field and a wheat field in Israel. We estimate gross primary productivity—a measure of ecosystem photosynthesis—directly from the carbonyl sulphide fluxes, and indirectly from carbon dioxide fluxes. The two estimates agree within an error of ±15%. The ratio of carbonyl sulphide to carbon dioxide flux at the ecosystem scale was consistent with the variability in mixing ratios observed on seasonal timescales in the background atmosphere. We suggest that atmospheric measurements of carbonyl sulphide flux could provide an independent constraint on estimates of gross primary productivity, key to projecting the response of the land biosphere to climate change.
Asmi, A., O'Dowd, C, Jennings, S.G., Weller, R, Flentie, H, Fjaeraa, A.M, Fiebig, M, Myhre, C.L, Hallar, A.G., Laj, P, M. Collaud Coen, J. A. Ogren, E. Andrews, P. Sheridan, A. Jefferson, E. Weingartner, U. Baltensperger, N. Bukowiecki, H. Lihavainen, N. Kivekäs, E. Asmi, P. P. Aalto, M. Kulmala, A. Wiedensohler, W. Birmili, A. Hamed, , (2013), Aerosol decadal trends – Part 2: In-situ aerosol particle number concentrations at GAW and ACTRIS stations, Atmospheric Chemistry and Physics, 13, 2, , 10.5194/acp-13-895-2013
Augustine, John A. and Ellsworth G Dutton, (2013), Variability of the surface radiation budget over United States from 1996 through 2011 from high-quality measurements, Journal of Geophysical Research, 118, , 10.1029/2012JD018551
Buller, D.B., Berwick, M., Shane, J., Lantz, K., Klein Buller, M., , (2013), User-centered Development of a Smart Phone Mobile Application Delivering Personalized Real-time Advice on Sun Protection, Translational Behavioral Medicine,
Collaud Coen, M., Weller, R, Weingartner, R, Virkkula, A, Sheridan, P, Schichtel, B.A., Ogren, J.A., O'Dowd, C, Lai, P, E. Andrews, A. Asmi, U. Baltensperger, N. Bukowiecki, D. Day, M. Fiebig, A. M. Fjaeraa, H. Flentje, A. Hyvärinen, A. Jefferson, S. G. Jennings, G. Kouvarakis, H. Lihavainen, C. Lund Myhre, W. C. Malm, N. Mihapopoulos, J. V. Molenar, , (2013), Aerosol decadal trends – Part 1: In-situ optical measurements at GAW and IMPROVE stations, Atmospheric Chemistry and Physics, 13, 2, , 10.5194/acp-13-869-2013
Gamon, John A., K. Fred Huemmrich, Robert S. Stone and Craig E. Tweedie, (2013), Spatial and temporal variation in primary productivity (NDVI) of coastal Alaskan tundra: Decreased vegetation growth following earlier snowmelt, Remote Sensing of Environment, 129, 144-153, 10.1016/j.rse.2012.10.030
Huang, M., G. R. Carmichael, T. Chai, R. B. Pierce, S. J. Oltmans, D. A. Jaffe, K. W. Bowman, A. Kaduwela, C. Cai, S. N. Spak, A. J. Weinheimer, L. G. Huey and G. S. Diskin, (2013), Impacts of transported background pollutants on summertime western US air quality: model evaluation, sensitivity analysis and data assimilation, Atmospheric Chemistry and Physics, 13, 1, , 10.5194/acp-13-359-2013
Lantz, K., Buller, D., Kane, I., Berwick, M., Buller, M.K., , (2013), Validation of an observed cloud fraction measure to modify a clear-sky UV Index for a erythema health application,
Michalsky, Joseph J. and G. B. Hodges, (2013), Field Measured Spectral Albedo–Four Years of Data from the Western U.S. Prairie, Journal of Geophysical Research: Atmospheres, , n/a-n/a, 10.1002/jgrd.50149
AbstractThis paper presents an initial look at four years of spectral measurements used to calculate albedo for the Colorado prairie just east of the Rocky Mountain range foothills. Some issues associated with calculating broadband albedo from thermopile sensors are discussed demonstrating that uncorrected instrument issues have led to incorrect conclusions. Normalized Difference Vegetative Index (NDVI) is defined for the spectral instruments in this study and used to demonstrate the dramatic changes that can be monitored with this very sensitive product. Examples of albedo wavelength and solar-zenith angle dependence for different stages of vegetative growth and senescence are presented. The spectral albedo of fresh snow and its spectral and solar-zenith angle dependence are discussed and contrasted with other studies of these dependencies. We conclude that fresh snow is consistent with a Lambertian reflector over the solar incidence angles measured; this is contrary to most snow albedo results. Even a slope of a degree or two in the viewed surface can explain the asymmetry in the morning and afternoon albedos for snow and vegetation. Plans for extending these spectral measurements for albedo to longer wavelengths and to additional sites are described.
Oltmans, S.J., A.S. Lefohn, D. Shadwick, J.M. Harris, H.E. Scheel, I. Galbally, D.W. Tarasick, B.J. Johnson, E.-G. Brunke, H. Claude, G. Zeng, S. Nichol, F. Schmidlin, J. Davies, E. Cuevas, A. Redondas, H. Naoe, T. Nakano and T. Kawasato, (2013), Recent tropospheric ozone changes – A pattern dominated by slow or no growth, Atmospheric Environment, 67, , 10.1016/j.atmosenv.2012.10.057
Petron, Gabrielle, Gregory J. Frost, Michael K. Trainer, Benjamin R Miller, Edward Dlugockencky and Pieter P. Tans, (2013), Reply to comment on "Hydrocarbon emissions characterization in the Colorado front range - A Pilot Study" by Michael A. Levi, Journal of Geophysical Research, , , 10.1029/2012JD018487
AbstractThe Comment by Levi (2012) on our paper, Pétron et al. (2012), presents a different interpretation of the atmospheric data and inventory estimates we used to derive our conclusions about methane emissions from oil and natural gas development in the Denver-Julesburg Basin (DJB) in Weld County, Colorado. Levi's (2012) Comment brings up new issues that point to the need for additional information. We maintain the value of the results derived in Pétron et al. (2012), particularly that vented and fugitive methane emissions from Weld County's fossil fuel exploration and production in 2008 were likely larger and more uncertain than values reported by emission inventories. Our findings rely on the interpretation of high-quality atmospheric observations using existing inventory data provided by the industry and regulatory agencies and on reasonable assumptions about the average vented raw gas composition. However, Levi (2012) has caused us to extend our analysis and to better characterize the uncertainties associated with his and with our approaches. In this Reply, we examine some critical limitations of the Pétron et al. (2012) and Levi (2012) interpretations of the atmospheric data using simple, two-source emission models that incorporate inventory data sets of unknown reliability. We present new evidence that the regulatory estimates of flashing emission and regulatory modeled composition profiles for a limited number of condensate tanks, the starting point for the calculations of Pétron et al. (2012) and Levi (2012), probably do not represent the true range of these parameters for the thousands of such sources across the DJB in 2008. The results of Levi (2012) suggest that leakage in Weld County in 2008 was biased toward dry gas wells, which disagrees with current inventories of venting and fugitive emissions in U.S. oil and gas fields, including the DJB. Most importantly, the indirect flux derivations undertaken by Levi (2012) and Pétron et al. (2012) highlight two inherent shortcomings common to most emissions inventories: their reliance on the extrapolation of very limited information and the difficulty in carrying out a full uncertainty analysis of such datasets. We agree with Levi (2012) that there is an urgent need to statistically document the composition profiles and magnitudes of significant sources in oil- and gas-producing fields. Observations-based methods with established uncertainties and that are completely independent of inventory information could directly quantify emission strengths and compositions of both point and aggregated area sources, providing an objective assessment of inventory methodology and estimates.
Rigby, M., Montzka, S.A., Dutton, G.S., R. G. Prinn, , (2013), Re-evaluation of the lifetimes of the major CFCs and CH3CCl3 using atmospheric trends, Atmospheric Chemistry and Physics, 13, 5, , 10.5194/acp-13-2691-2013
Sharma, S., M. Ishizawa, D. Chan, D. Lavoué, E. Andrews, K. Eleftheriadis and S. Maksyutov, (2013), 16-year simulation of Arctic black carbon: transport, source contribution, and sensitivity analysis on deposition, Journal of Geophysical Research: Atmospheres, , n/a-n/a, 10.1029/2012JD017774
AbstractArctic regional climate is influenced by the radiative impact of aerosol black carbon (BC) both in the atmosphere and deposited on the snow and ice covered surfaces. The NIES (National Institute for Environmental Studies) global atmospheric transport model was used, with BC emissions from mid-latitude fossil fuel and biomass burning source regions, to simulate BC concentrations with 16 year period. The model-simulated BC agreed well with the BC observations, including the trends and seasonality, at three Arctic sites: Alert (Nunavut, Canada), Barrow (Alaska, USA), and Zepplin, Ny-Ålesund (Svalbard, Norway). The equivalent black carbon (EBC, absorption inferred BC) observations at the three Arctic locations showed an overall decline of 40% from 1990 to 2009; with most change occurring during early 1990s. Model simulations confirmed declining influence on near surface BC contribution by 70% , and atmospheric BC burden by one half from the Former Soviet Union (FSU) BC source region over 16 years. In contrast, the BC contribution from the East Asia (EA) region has little influence at the surface but atmospheric Arctic BC burden increased by 3 folds. Modelled dry deposition is dominant in the Arctic during wintertime, while wet deposition prevails at all latitudes during summer. Sensitivity analyses on the dry and wet deposition schemes indicate that parameterizations need to be refined to improve on the model performance. There are limitations in the model due to simplified parameterizations and remaining model uncertainties, which requires further exploration of source region contributions, especially from growing EA source region to Arctic BC levels in the future is warranted.
Tans, P., (2013), Allocation of terrestrial carbon sources using 14CO2; measurement and modeling,
The radiocarbon content of whole air provides a theoretically ideal and now observationally proven tracer for recently-‐added fossil fuel derived CO2 in the atmosphere (Cff). Over large industrialized land areas, determination of Cff also constrains the change in CO2 due to uptake and release by the terrestrial biosphere. Here we review the development of a Δ14CO2 measurement program and its implementation within the NOAA Global Monitoring Division’s air sampling network, using the US as an example. The Δ14CO2 measurement repeatability is evaluated based on surveillance cylinders of whole air and equates to a Cff detection limit of ≤0.9 ppm based on measurement uncertainties alone. We also attempt to quantify additional sources of uncertainty arising from non-‐fossil terms in the atmospheric 14CO2 budget and from uncertainties in the composition of “background” air against which Cff enhancements occur. As an example of how we apply the measurements, we present estimates of the boundary layer enhancements of Cff and Cbio using observations obtained from vertical airborne sampling profiles off of the northeastern US. We also present an updated time series of measurements from NOAA GMD’s Niwot Ridge site at 3475 m asl in Colorado in order to characterize recent Δ14CO2 variability in the well-‐ mixed free troposphere.
Wang, Kaicun, Robert E. Dickinson, Qian Ma, John A. Augustine and Martin Wild, (2013), Measurement Methods Affect the Observed Global Dimming and Brightening, Journal of Climate, , , 10.1175/JCLI-D-12-00482.1
Surface incident solar radiation (G) determines our climate and environment. G has been widely observed with a single pyranometer since the late 1950s. Such observations have suggested a widespread decrease between the 1950s and 1980s (“global dimming”), i.e., at a rate of -3.5 W m−2 per decade (or -2% per decade) from 1960 to 1990. Since the early 1990s, the diffuse and direct components of G have been measured independently and a more accurate G was calculated by summing these two measurements. Data from this summation method have suggested that G has increased at a rate of 6.6 W m−2 per decade (3.6% per decade) from 1992 to 2002 (“brightening”) at selected sites. The brightening rates from these studies were also higher than those from a single pyranometer. In this paper, we used 17 years (1995-2011) parallel measurements by the two methods from nearly 50 stations to test whether these two measurement methods of G provide similar long-term trends. Our results show that although measurements of G by the two methods agree very well on a monthly time scale, the long-term trend from 1995 to 2011 determined by the single pyranometer is 2-4 W m−2 per decade less than that from the summation method. This difference of trends in the observed G is statistically significant. The dependence of trends of G on measurement methods uncovered here has an important implication for the widely reported “global dimming” and “brightening” based on datasets collected by different measurement methods, i.e., the dimming might have been less if measured with current summation methods.
Ziska, F., B. Quack, K. Abrahamsson, S. D. Archer, E. Atlas, T. Bell, J. H. Butler, L. J. Carpenter, C. E. Jones, N. R. P. Harris, H. Hepach, K. G. Heumann, C. Hughes, J. Kuss, K. Krüger, P. Liss, R. M. Moore, A. Orlikowska, S. Raimund, C. E. Reeves, W. Reifenhäuser, A. D. Robinson, C. Schall, T. Tanhua, S. Tegtmeier, S. Turner, L. Wang, D. Wallace, J. Williams, H. Yamamoto, S. Yvon-Lewis and Y. Yokouchi, (2013), Global sea-to-air flux climatology for bromoform, dibromomethane and methyl iodide, Atmospheric Chemistry and Physics Discussions, 13, 2, , 10.5194/acpd-13-5601-2013