Publications Published in 2004

1. Abrupt climate change around 22 ka on the Siple Coast of Antarctica. Taylor, K C; White, J W C; Severinghaus, J. P.; Brook, E J; Mayweski, P A; Alley, R B; Steig, E J; Spencer, M K; Meyerson, E; Meese, D A; Lamorey, G W; Grachev, A; Gow, A J; Barnett, B A.
   Quaternary Science Reviews: 2004
   Notes
   A new ice core from Siple Dome, Antarctica suggests the surface temperature increased by B6 C in just several decades at approximately 22 ka BP. This abrupt change did not occur 500km away in the Byrd ice core, or in climate proxy records in the Siple Dome core indicative of the mid-latitude Pacific. This demonstrates there was significant spatial heterogeneity in the response of the Antarctic climate during the last deglaciation and draws attention to unexplained mechanisms of abrupt climate change in Antarctica.
   
   
   
2. Accelerated Sea-Level Rise from West Antarctica. Thomas, R.; Rignot, E.; Casassa, G.; Kanagaratnam, P.; Acuna, C.; Akins, T.; Brecher, H.; Frederick, E..
   Science: 2004
   DOI: 10.1126/science.1099650
   Notes
   Recent aircraft and satellite laser altimeter surveys of the Amundsen Sea sector of West Antarctica show that local glaciers are discharging about 250 cubic kilometers of ice per year to the ocean, almost 60% more than is accumulated within their catchment basins. This discharge is sufficient to raise sea level by more than 0.2 millimeters per year. Glacier thinning rates near the coast during 2002-2003 are much larger than those observed during the 1990s. Most of these glaciers flow into floating ice shelves over bedrock up to hundreds of meters deeper than previous estimates, providing exit routes for ice from further inland if ice-sheet collapse is under way.
   
   
   
3. ACE-ASIA: Regional Climatic and Atmospheric Chemical Effects of Asian Dust and Pollution. Seinfeld, John H; Carmichael, Gregory R; Arimoto, Richard; Conant, William C; Brechtel, Frederick J; Bates, Timothy S; Cahill, Thomas A; Clarke, Antony D.; Doherty, Sarah J..
   American Meterological Society: 2004
   Notes
   Although continental-scale plumes of Asian dust and pollution reduce the amount of solar radiation reaching the earth's surface and perturb the chemistry of the atmosphere, our ability to quantify these effects has been limited by a lack of critical observations, particularly of layers above the surface. Comprehensive surface, airborne, shipboard, and satellite measurements of Asian aerosol chemical composition, size, optical properties, and radiative impacts were performed during the Asian Pacific Regional Aerosol Characterization Experiment (ACE-Asia) study. Measurements within a massive Chinese dust storm at numerous widely spaced sampling locations revealed the highly complex structure of the atmosphere, in which layers of dust, urban pollution, and biomass-burning smoke may be transported long distances as distinct entities or mixed together. The data allow a first-time assessment of the regional climatic and atmospheric chemical effects of a continental-scale mixture of dust and pollution. Our results show that radiative flux reductions during such episodes are sufficient to cause regional climate change.
   
   
   
4. A comprehensive set of high-resolution grids of monthly climate for Europe and the globe: the observed record (1901-2000) and 16 scenarios (2001-2100). Mitchell, Timothy D; Carter, Timothy R; Jones, Philip D; Hulme, Mike; New, Mark.
   Tyndall Centre for Climate Change Research: 2004
   Notes
   The authors describe the construction of a comprehensive set of high-resolution grids of monthly climate at spatial resolutions of 10 minutes for Europe and 0.5 degrees for the global land surface. Five climate variables are included: temperature, diurnal temperature range, precipitation, vapour pressure, and cloud cover. The set comprises the observed climate record (1901–2000), a control scenario (1901–2100) and 16 scenarios of projected future climate (2001–2100). The 16 climate change scenarios represent all combinations of four emissions scenarios and four global climate models (GCMs), covering 93% of the range of uncertainty in global warming in the 21st century published by the Intergovernmental Panel on Climate Change. Thus these scenarios permit users to assess the implications for climate impacts of some of the major sources of uncertainty in future climate. The scenarios were constructed by combining time-series of global warming and patterns of change from GCMs with the baseline climate and sub-centennial variability from the observed record. Thus these grids provide homogenous 200-year transient scenarios (1901–2100) for users projecting the future impacts of climate change using environmental models. These grids are publicly available through the Climatic Research Unit.
   
   
   
5. Aerosol distribution in the Northern Hemishpere during ACE-Asia: Results from global model, satellite observations, and Sun photometer measurements. Chin, Mian; Chu, Allen; Levy, Robert; Remer, Lorraine; Kaufman, Yoram; Holben, Brent; Eck, Tom; Ginoux, Paul; Gao, Qinqxian.
   Journal of Geophysical Research: 2004
   Notes
   [1] We analyze the aerosol distribution and composition in the Northern Hemisphere during the Asian Pacific Regional Aerosol Characterization Experiment (ACE-Asia) field experiment in spring 2001. We use the Goddard Chemistry Aerosol Radiation and Transport (GOCART) model in this study, in conjunction with satellite retrieval from the Moderate- resolution Imaging Spectroradiometer (MODIS) on EOS-Terra satellite and Sun photometer measurements from the worldwide erosol Robotic Network (AERONET). Statistical analysis methods including histograms, mean bias, root-meansquare error, correlation coefficients, and skill scores are applied to quantify the differences between the MODIS 1
   
   
   
6. Aerosol indirect effects in POLDER satellite data and the Laboratoire de Météorologie Dynamique-Zoom (LMDZ) general circulation model. Quaas, J.; Boucher, O.; Bréon, F.M..
   Journal of Geophysical Research: 2004
   Notes
   The POLDER-1 instrument was able to measure aerosol and cloud properties for eight months in 1996–1997. We use these observational data for aerosol concentration (the aerosol index), cloud optical thickness, and cloud droplet effective radius to establish statistical relationships among these parameters in order to analyze the first and second aerosol indirect effects. We also evaluate the representation of these effects as parameterized in the Laboratoire de Météorologie Dynamique–Zoom (LMDZ) general circulation model. We find a decrease in cloud top droplet radius with increasing aerosol index in both the model and the observations. Our results are only slightly changed if the analysis is done at fixed cloud liquid water path (LWP) instead of considering all LWP conditions. We also find a positive correlation between aerosol index and cloud liquid water path, which is particularly pronounced over the Northern Hemisphere midlatitudes. This may be interpreted as observational evidence for the second aerosol indirect effect on a large scale. The model-simulated relationship agrees well with that derived from POLDER data. Model simulations show a rather small change in the two relationships if preindustrial rather than present-day aerosol distributions are used. However, when entirely switching off the second aerosol indirect effect in our model, we find a much steeper slope than we do when including it.
   
   
   
7. Air pollution related deaths during the 2003 heat wave in the Netherlands. Fischer, Paul H; Brunekreef, Bert; Lebret, Erik.
   Atmospheric Environment: 2004
   Notes
   In the Netherlands an excess of 1000–1400 deaths was estimated due to the hot temperatures that occurred during the 2003 summer period. We estimated the number of deaths attributable to the ozone and Particular Matter (PM10) concentrations in the summer period June–August 2003. Our calculations show that an excess of around 400–600 air pollution-related deaths may have occurred compared to an ‘average’ summer. These calculations suggest that in the Netherlands, a significant proportion of the deaths now being attributed to the hot summer weather can reasonably be expected to have been caused by air pollution.
   
   
   
8. All downhill from here?. Krajick, Kevin.
   Science: 2004
   
   
9. A Method for Prediction of California Summer Air Surface Temperature. E.ALFARO,A.GERSHUNOV,D.CAYAN, A. STEINEMANN,D.PIERCE, T. BARNETT.
   EOS: 2004
   
   
10. A methodology to asess relations between climatic variability and variations in hydrologic time series in the southwestern United States. Hanson, R T; Newhouse, M W; Dettinger, M D.
    Journal of Hydrology: 2004
    Notes
    A new method for frequency analysis of hydrologic time series was developed to facilitate the estimation and reconstruction of individual or groups of frequencies from hydrologic time-series and facilitate the comparison of these isolated time-series components across data types, between different hydrologic settings within a watershed, between watersheds, and across frequencies. While climate-related variations in inflow to and outflow from aquifers have often been neglected, the development and management of ground-water and surface-water resources has required the inclusion of the assessment of the effects of climatic variability on the supply and demand and sustainability of use. The regional assessmentof climatic variability of surface-water and ground-water flow throughout the southwestern United States required this new systematic method of hydrologic time-series analysis. To demonstrate the application of this new method, six hydrologic time-series from the Mojave River Basin, California were analyzed. The results indicate that climatic variability exists in all the data types and are partially coincident with known climate cycles such as the Pacific Decadal Oscillation and the El Nino–Southern Oscillation. The time-series also indicate lagged correlations between tree-ring indices, streamflow, stream base flow, and ground-water levels. These correlations and reconstructed time-series can be used to better understand the relation of hydrologic response to climatic forcings and to facilitate the simulation of streamflow and ground-water recharge for a more realistic approach to water-resource management.