Bulletin of the American Physical Society
APS March Meeting 2015
Volume 60, Number 1
Monday–Friday, March 2–6, 2015; San Antonio, Texas
Session D33: Focus Session: The Physics of Climate II |
Hide Abstracts |
Sponsoring Units: GPC DFD Chair: Juan Restrepo, Oregon State University Room: 208 |
Monday, March 2, 2015 2:30PM - 2:42PM |
D33.00001: Scattering and Absorption of E\&M radiation by small particles-applications to study impact of biomass aerosols on climate Solomon Bililign, Sujeeta Singh, Marc Fiddler, Damon Smith The phenomena of scattering, absorption, and emission of light and other electromagnetic radiation by small particles are central to many science and engineering disciplines. Absorption of solar radiation by black carbon aerosols has a significant impact on the atmospheric energy distribution and hydrologic processes. By intercepting incoming solar radiation before it reaches the surface, aerosols heat the atmosphere and, in turn, cool the surface. The magnitude of the atmospheric forcing induced by anthropogenic absorbing aerosols, mainly black carbon (BC) emitted from biomass burning and combustion processes has been suggested to be comparable to the atmospheric forcing by all greenhouse gases (GHGs). Despite the global abundance of biomass burning for cooking, forests clearing for agriculture and wild fires, the optical properties of these aerosols have not been characterized at wide range of wavelengths. Our laboratory uses a combination of Cavity ring down spectroscopy and integrating nephelometry to measure optical properties of (extinction, absorption and scattering coefficients) of biomass aerosols. Preliminary results will be presented. [Preview Abstract] |
Monday, March 2, 2015 2:42PM - 2:54PM |
D33.00002: Observations Determination of Surface Radiative Forcing by CO2 and CH4 William Collins, Daniel Feldman, Jonathan Gero, Margaret Torn, Eli Mlawer, Timothy Shippert Earth's background atmospheric CO2 and CH4 concentrations have been steadily rising due to anthropogenic emissions, and these increases since 1750 have implications for the radiative balance of the Earth's atmosphere. The physics governing how atmospheric CO2 and CH4, both well-mixed greenhouse gases (WMGHGs), influence atmospheric infrared energy balance, and thus climate, are well established, but the impact of recent atmospheric WMGHG trends on the surface energy balance has not been experimentally confirmed in the field. Using infrared WMGHG absorption bands and controlling for atmospheric temperature and water vapor, spectra from the DOE ARM Program's Atmospheric Emitted Radiance Interferometers (AERI) yield the first direct observational evidence of the time-series of WMGHG surface radiative forcing directly attributable to recent increases in WMGHGs, in this case between 2000-2010. The time-series shows a secular trend of in the radiative forcing from both CO2 and CH4. This data record provides the first comprehensive observational evidence of surface radiative forcing by WMGHGs, confirming theoretical predictions of the atmospheric greenhouse effect. [Preview Abstract] |
Monday, March 2, 2015 2:54PM - 3:06PM |
D33.00003: Interaction between carbon dioxide and coal: atomic-scale characteristics and electronic structures Yingdi Liu, Sanwu Wang Geologic sequestration of CO$_{\mathrm{2}}$ in unmineable coal seams has been suggested to mitigate the effect of the increasing of the atmospheric CO$_{\mathrm{2}}$ concentration on global warming. Extensive experimental studies have been performed for the injection of CO$_{\mathrm{2}}$ into coalbeds. However, the atomic-level mechanism for the interaction between CO$_{\mathrm{2}}$ and coal has not been fully explored. We report first-principles density-functional calculations and \textit{ab initio} molecular dynamics simulations for the interaction between CO$_{\mathrm{2}}$ and the coal network. In particular, we report results about atomic-scale and electronic properties of the interaction. We also report a comparison with the interaction between CH$_{\mathrm{4}}$ and coal. [Preview Abstract] |
Monday, March 2, 2015 3:06PM - 3:42PM |
D33.00004: Polar Oceanography, Arctic Sea Ice and Climate Invited Speaker: Mary-Louise Timmermans Intensive sampling from oceanographic moorings, shipboard measurements, and drifting autonomous buoy systems has brought new understanding to Arctic freshwater dynamics, ocean heat and mixing processes, circulation and eddies, and atmosphere-ice-ocean interactions. Observations indicate apparently rapid changes in the basin-scale freshwater distribution that have marked effects on Arctic stratification. Recent measurements support the idea that a strengthened stratification limits the vertical flux of deep-ocean heat. All ocean layers exhibit a rich mesoscale eddy field; eddies, with scales comparable to the Rossby Deformation Radius [O(10km)], transport water and heat over long distances and enhance ocean mixing. Measurements further reveal an active submesoscale flow field in the ocean surface layer. These upper-ocean features, having length scales of a few kilometers or less, are dynamically important in that they can impede surface-layer deepening and modify heat, salt, and momentum fluxes between the surface ocean and adjacent sea-ice cover. This talk will review highlights of recent Arctic Ocean observational studies across a range of temporal and spatial scales, and outline advances in our understanding of ocean drivers of sea ice and climate change. [Preview Abstract] |
Monday, March 2, 2015 3:42PM - 3:54PM |
D33.00005: Study of Aerosol Chemical Composition Based on Aerosol Optical Properties Austin Berry, Rudra Aryal We investigated the variation of aerosol absorption optical properties obtained from the CIMEL Sun-Photometer measurements over three years (2012-2014) at three AERONET sites GSFC; MD Science\textunderscore Center and Tudor Hill, Bermuda. These sites were chosen based on the availability of data and locations that can receive different types of aerosols from land and ocean. These absorption properties, mainly the aerosol absorption angstrom exponent, were analyzed to examine the corresponding aerosol chemical composition. We observed that the retrieved absorption angstrom exponents over the two sites, GSFC and MD Science Center, are near 1 (the theoretical value for black carbon) and with low single scattering albedo values during summer seasons indicating presence of black carbon. Strong variability of aerosol absorption properties were observed over Tudor Hill and will be analyzed based on the air mass embedded from ocean side and land side. We will also present the seasonal variability of these properties based on long-range air mass sources at these three sites. [Preview Abstract] |
Follow Us |
Engage
Become an APS Member |
My APS
Renew Membership |
Information for |
About APSThe American Physical Society (APS) is a non-profit membership organization working to advance the knowledge of physics. |
© 2024 American Physical Society
| All rights reserved | Terms of Use
| Contact Us
Headquarters
1 Physics Ellipse, College Park, MD 20740-3844
(301) 209-3200
Editorial Office
100 Motor Pkwy, Suite 110, Hauppauge, NY 11788
(631) 591-4000
Office of Public Affairs
529 14th St NW, Suite 1050, Washington, D.C. 20045-2001
(202) 662-8700