Radiative forcing of the direct aerosol effect from AeroCom Phase II simulations Atmospheric Chemistry and Physics DOI 10.5194/acp-13-1853-2013 19 February 2013 We report on the AeroCom Phase II direct aerosol effect (DAE) experiment where 16 detailed global aerosol models have been used to simulate the changes in the aerosol distribution over the industrial era. All 16 models have estimated the radiative forcing of the anthropogenic DAE, and have taken into account anthropogenic sulphate, black carbon and organic aerosols from fossil fuel, biofuel, and biomass burning emissions. Read more
The effect of hygroscopicity on eddy covariance estimates of sea-spray aerosol fluxes: a comparison of high-rate and bulk correction methods Atmospheric Measurement Techniques DOI 10.5194/amt-6-323-2013 13 February 2013 Here we describe a method of correcting aerosol spectra for relative humidity induced size variations at the high frequency (10 Hz) measurement timescale, where counting statistics are poor and the spectral shape cannot be well represented by a simple power law. Read more
The importance of glacier and forest change in hydrological climate-impact studies Hydrology and Earth System Sciences DOI 10.5194/hess-17-619-2013 11 February 2013 Changes in land cover alter the water balance components of a catchment, due to strong interactions between soils, vegetation and the atmosphere. Therefore, hydrological climate impact studies should also integrate scenarios of associated land cover change. To reflect two severe climate-induced changes in land cover, we applied scenarios of glacier retreat and forest cover increase that were derived from the temperature signals of the climate scenarios used in this study. Read more
Application of the Statistical Oxidation Model (SOM) to Secondary Organic Aerosol formation from photooxidation of C12 alkanes Atmospheric Chemistry and Physics DOI 10.5194/acp-13-1591-2013 8 February 2013 We apply the Statistical Oxidation Model of Cappa and Wilson (2012) to model the formation of the secondary organic aerosol from the formation of the four C12 alkanes, dodecane, 2-methyl undecane, cyclododecane and hexylcyclohexane, under both high- and low-NOxconditions, based upon data from the Caltech chambers. SOM) to Secondary Organic Aerosol formation from photooxidation of C12 alkanes">Read more
Brief Communication: Expansion of meltwater lakes on the Greenland Ice Sheet The Cryosphere DOI 10.5194/tc-7-201-2013 1 February 2013 Forty years of satellite imagery reveal that meltwater lakes on the margin of the Greenland Ice Sheet have expanded substantially inland to higher elevations with warming. These lakes are important because they provide a mechanism for bringing water to the ice bed, causing sliding. Read more
High-latitude cooling associated with landscape changes from North American boreal forest fires Biogeosciences DOI 10.5194/bg-10-699-2013 1 February 2013 Here we simulated changes in forest composition due to altered burn area using a stochastic model of fire occurrence, historical fire data from national inventories, and succession trajectories derived from remote sensing. Read more
What could have caused pre-industrial biomass burning emissions to exceed current rates? Climate of the Past DOI 10.5194/cp-9-289-2013 31 January 2013 Recent studies based on trace gas mixing ratios in ice cores and charcoal data surprisingly indicate that biomass burning emissions over the past millennium exceeded contemporary emissions by up to a factor of 4 for certain time periods. We have analysed how emissions from several landscape biomass burning sources could have fluctuated to yield emissions that are in correspondence with recent results based on ice core mixing ratios of carbon monoxide and its isotopic signature measured at South Pole station. Read more
Identifying urban sources as cause of elevated grass pollen concentrations using GIS and remote sensing Biogeosciences DOI 10.5194/bg-10-541-2013 29 January 2013 We examine here the hypothesis that during flowering, the grass pollen concentrations at a specific site reflect the distribution of grass pollen sources within a few kilometres of this site. We perform this analysis on data from a measurement campaign in the city of Aarhus (Denmark) using three pollen traps and by comparing these observations with a novel inventory of grass pollen sources. GIS and remote sensing">Read more
On the nature of rainfall intermittency as revealed by different metrics and sampling approaches Hydrology and Earth System Sciences DOI 10.5194/hess-17-355-2013 29 January 2013 Results of this work may be useful to improve the calibration of stochastic algorithms used to downscale coarse rainfall predictions of climate and weather forecasting models, as well as the parameterization of intensity-duration-frequency curves, adopted for land planning and design of civil infrastructures. Read more
Similarity of climate control on base flow and perennial stream density in the Budyko framework Hydrology and Earth System Sciences DOI 10.5194/hess-17-315-2013 25 January 2013 Perennial stream density (DP), which is obtained from the high resolution National Hydrography Dataset, for 185 watersheds declines monotonically with climate aridity index, and an inversely proportional function is proposed to model the relationship between DPand the ratio of potential evaporation to precipitation. Read more
