Growth of nucleation mode particles in the summertime Arctic: a case study Atmospheric Chemistry and Physics DOI 10.5194/acp-16-7663-2016 23 June 2016 We present a case study focused on an aerosol growth event observed in the Canadian High Arctic during summer. Using measurements of aerosol chemical and physical properties we find evidence for aerosol growth into cloud condensation nuclei-active sizes, through marine-influenced secondary organic aerosol formation. Understanding the mechanisms that control the formation and growth of aerosol is crucial for our ability to predict cloud properties, and therefore radiative balance and climate. Read more
Greenland Ice Sheet seasonal and spatial mass variability from model simulations and GRACE (2003–2012) The Cryosphere DOI 10.5194/tc-10-1259-2016 20 June 2016 We compared satellite-derived estimates of spatial and seasonal variations in Greenland Ice Sheet mass with a set of model simulations, revealing an agreement between models and satellite estimates for the ice-sheet-wide seasonal fluctuations in mass, but disagreement at finer spatial scales. The model simulations underestimate low-elevation mass loss. Improving the ability of models to capture variations and trends in Greenland Ice Sheet mass is important for estimating future sea level rise. Read more
A 7-year dataset for driving and evaluating snow models at an Arctic site (Sodankylä, Finland) Geoscientific Instrumentation, Methods and Data Systems DOI 10.5194/gi-5-219-2016 16 June 2016 Physically based models that predict the properties of snow on the ground are used in many applications, but meteorological input data required by these models are hard to obtain in cold regions. Monitoring at the Sodankyla research station allows construction of model input and evaluation datasets covering several years for the first time in the Arctic. The data are used to show that a sophisticated snow model developed for warmer and wetter sites can perform well in very different conditions. Read more
Spring bloom onset in the Nordic Seas Biogeosciences DOI 10.5194/bg-13-3485-2016 15 June 2016 We investigated the bloom onset in the Nordic Seas using 6 bio-optical floats. We found that the float data are consistent with two possible scenarios for the onset of blooms in the Nordic Seas. The Nordic Seas blooms could have started either when the light became sufficiently abundant that the division rates exceeded the loss rates, or when the photoperiod, the number of daily light hours experienced by phytoplankton, exceeded a critical value. Read more
Estimate of changes in agricultural terrestrial nitrogen pathways and ammonia emissions from 1850 to present in the Community Earth System Model Biogeosciences DOI 10.5194/bg-13-3397-2016 13 June 2016 Future increases are predicted in the amount of nitrogen produced as manure or used as synthetic fertilizer in agriculture. However, the impact of climate on the subsequent fate of this nitrogen has not been evaluated. Here we describe, analyze and evaluate the FAN (flows of agricultural nitrogen) process model that simulates the the climate-dependent flows of nitrogen from agriculture. The FAN model is suitable for use within a global terrestrial climate model. Read more
Modeling 25 years of spatio-temporal surface water and inundation dynamics on large river basin scale using time series of Earth observation data Hydrology and Earth System Sciences DOI 10.5194/hess-20-2227-2016 10 June 2016 We statistically modeled surface water extent (SWE) and inundation dynamics from a unique Landsat-based time series (1986–2011) for Australia’s Murray–Darling Basin as a function of river flow and spatially explicit time series of rainfall, evapotranspiration and soil moisture. We present a data-driven and transferable approach that allowed us to model SWE through periods of flooding and drying for 363 floodplain units and to identify local combinations of variables that drive SWE dynamics. Read more
Return glider radiosonde for in situ upper-air research measurements Atmospheric Measurement Techniques DOI 10.5194/amt-9-2535-2016 9 June 2016 New radiosonde instruments for humidity-, radiation- and gas-profile measurements were introduced in recent years for atmospheric research and climate monitoring. Such instruments are intended to be reused on multiple flights. Here we introduce the return glider radiosonde (RGR), which enables flying and retrieving valuable in situ upper-air instruments. The RGR is lifted with weather balloons to a preset altitude, and a built-in autopilot flies the glider autonomously back to the launch site. Read more
Causes and systematics of inundations of the Krasnodar territory on the Russian Black Sea coast Natural Hazards and Earth System Sciences DOI 10.5194/nhess-16-1289-2016 8 June 2016 Inundations on the Black Sea coast of the Krasnodar territory of the Russian Federation were analysed for 1945 to 2013. Risks, hazards and damage from inundations here are some of the highest in the country. The large quantity and the extremeness of rainfall, and the intense flood regimes of the rivers are the main contributors. Additionally, anthropogenic impact such as badly planned economic activities in channels, floodplains and on river watersheds strongly enhance the effects. Read more
High spatial resolution imaging of methane and other trace gases with the airborne Hyperspectral Thermal Emission Spectrometer (HyTES) Atmospheric Measurement Techniques DOI 10.5194/amt-9-2393-2016 1 June 2016 Using data from a new airborne Hyperspectral Thermal Emission Spectrometer (HyTES) instrument, we present a technique for the detection and wide-area mapping of emission plumes of methane and other atmospheric trace gas species over challenging and diverse environmental conditions with high spatial resolution, that permits direct attribution to sources in complex environments. Read more
Will a perfect model agree with perfect observations? The impact of spatial sampling Atmospheric Chemistry and Physics DOI 10.5194/acp-16-6335-2016 24 May 2016 We show that evaluating global aerosol model data with observations of very different spatial scales (200 vs. 10 km) can lead to large discrepancies, solely due to different spatial sampling. Strategies for reducing these sampling errors are developed and tested using a set of high-resolution model simulations. Read more
Retrieving atmospheric turbulence information from regular commercial aircraft using Mode-S and ADS-B Atmospheric Measurement Techniques DOI 10.5194/amt-9-2253-2016 23 May 2016 This paper is presenting a feasibility study focused on methods of estimating the turbulence intensity based on a class of navigational messages routinely broadcast by the commercial aircraft (known as ADS-B and Mode-S). Using this kind of information could have potentially significant impact on aviation safety. Three methods have been investigated. Read more
Investigating the impact of land-use land-cover change on Indian summer monsoon daily rainfall and temperature during 1951–2005 using a regional climate model Hydrology and Earth System Sciences DOI 10.5194/hess-20-1765-2016 10 May 2016 Regional climate model (RegCM4) simulations demonstrate that part of the observed decrease in moderate rainfall events during the summer monsoon season over central India from 1951 to 2005 is attributed to anthropogenically induced land-use land-cover change (LULCC). LULCC also partly explains the observed warming trend in the daily mean and maximum temperatures over India. This study demonstrates the importance of LULCC in the context of regional climate change over India. Read more
Alluvial plain dynamics in the southern Amazonian foreland basin Earth System Dynamics DOI 10.5194/esd-7-453-2016 10 May 2016 This paper analyses the behaviour of 12 tributaries of the Río Mamoré and their influence on alluvial plain dynamics. These rivers are extremely active: between 1984 and 2014, 7 of these 12 rivers underwent a total of 41 crevasses and 29 avulsions. Most of the sedimentary load of these rivers is deposited on the alluvial plains before they reach the Mamoré. Crevasses and avulsions are not controlled by ENSO cycles, but rather are the result of intrabasinal processes. Read more
Bayesian statistical ionospheric tomography improved by incorporating ionosonde measurements Atmospheric Measurement Techniques DOI 10.5194/amt-9-1859-2016 28 April 2016 We validate 2-D ionospheric tomography reconstructions against EISCAT incoherent scatter radar measurements. The method is based on Bayesian statistical inversion. We employ ionosonde measurements for the choice of the prior distribution parameters and use a sparse matrix approximation for the computations. This results in a computationally efficient tomography algorithm with clear probabilistic interpretation. We find that ionosonde measurements improve the reconstruction significantly. Read more
Mapping turbulent diffusivity associated with oceanic internal lee waves offshore Costa Rica Ocean Science DOI 10.5194/os-12-601-2016 26 April 2016 Lee waves play a significant role in ocean mixing but are difficult to study with traditional casts, moorings, and tows due to their stationary nature and limited spatial extent. We develop a new method to estimate turbulent diffusivity from seismic data and find elevated levels of turbulence associated with lee waves in the mid-water and around the seafloor that are 5 times greater than surrounding waters and 50 times greater than open-ocean diffusivities. Read more
A Late Pleistocene sea level stack Climate of the Past DOI 10.5194/cp-12-1079-2016 26 April 2016 This study presents an average of seven Late Pleistocene sea level records, which improves the signal-to-noise ratio for estimates of sea level change during glacial cycles of the past 800 000 years. Read more
Revolutions in energy input and material cycling in Earth history and human history Earth System Dynamics DOI 10.5194/esd-7-353-2016 22 April 2016 We identify six past revolutions in energy input and material cycling in Earth and human history. We find that human energy use has now reached a magnitude comparable to the biosphere, and conclude that a prospective sustainability revolution will require scaling up new solar energy technologies and the development of much more efficient material recycling systems. Our work was inspired by recognising the connections between Earth system science and industrial ecology at the “LOOPS” workshop. Read more
Differential climate impacts for policy-relevant limits to global warming: the case of 1.5 ∘C and 2 ∘C Earth System Dynamics DOI 10.5194/esd-7-327-2016 21 April 2016 We present for the first time a comprehensive assessment of key climate impacts for the policy relevant warming levels of 1.5 °C and 2 °C above pre-industrial levels. We report substantial impact differences in intensity and frequency of extreme weather events, regional water availability and agricultural yields, sea-level rise and risk of coral reef loss. The increase in climate impacts is particularly pronounced in tropical and sub-tropical regions. Read more
Effects of wood chip amendments on the revegetation performance of plant species on eroded marly terrains in a Mediterranean mountainous climate (Southern Alps, France) Solid Earth DOI 10.5194/se-7-599-2016 15 April 2016 This paper presents the results of two experiments of revegetation techniques in context of water erosion and mountainous Mediterranean climate. We studied the interest of a wood chip amendment, applied on soil surface (mulch), and its interaction with plant development. The use of different plant species and the monitoring on three growing seasons (with climatic variations) allow us to specify the interest of wood chip mulch to improve revegetation especially in erosion and drought conditions. Read more
The link between marine sediment records and changes in Holocene Saharan landscape: simulating the dust cycle Climate of the Past DOI 10.5194/cp-12-1009-2016 15 April 2016 We demonstrate for the first time the direct link between dust accumulation in marine sediment cores and Saharan land surface by simulating the mid-Holocene and pre-industrial dust cycle as a function of Saharan land surface cover and atmosphere-ocean conditions using the coupled atmosphere-aerosol model ECHAM6-HAM2.1. Mid-Holocene surface characteristics, including vegetation cover and lake surface area, are derived from proxy data and simulations. Read more