Regional Antarctic snow accumulation over the past 1000 years Climate of the Past DOI 10.5194/cp-13-1491-2017 10 November 2017 Regional Antarctic snow accumulation derived from 79 ice core records is evaluated as part of the PAGES Antarctica 2k working group. Our results show that surface mass balance for the total Antarctic ice sheet has increased at a rate of 7 ± 0.13 Gt dec-1 since 1800 AD, representing a net reduction in sea level of ~ 0.02 mm dec-1 since 1800 and ~ 0.04 mm dec-1 since 1900 AD. The largest contribution is from the Antarctic Peninsula. Read more
Towards representing human behavior and decision making in Earth system models – an overview of techniques and approaches Earth System Dynamics DOI 10.5194/esd-8-977-2017 8 November 2017 Today, human interactions with the Earth system lead to complex feedbacks between social and ecological dynamics. Modeling such feedbacks explicitly in Earth system models (ESMs) requires making assumptions about individual decision making and behavior, social interaction, and their aggregation. In this overview paper, we compare different modeling approaches and techniques and highlight important consequences of modeling assumptions. We illustrate them with examples from land-use modeling. Read more
Making better sense of the mosaic of environmental measurement networks: a system-of-systems approach and quantitative assessment Geoscientific Instrumentation, Methods and Data Systems DOI 10.5194/gi-6-453-2017 6 November 2017 The term system-of-systems with respect to observational capabilities is frequently used, but what does it mean and how can it be assessed? Here, we define one possible interpretation of a system-of-systems architecture that is based upon demonstrable aspects of observing capabilities. We develop a set of assessment strands and then apply these to a set of atmospheric observational networks to decide which observations may be suitable for characterising satellite platforms in future work. Read more
Methanesulfonic acid (MSA) migration in polar ice: data synthesis and theory The Cryosphere DOI 10.5194/tc-11-2439-2017 3 November 2017 We combine a synthesis of 22 ice core records and a model of soluble impurity transport to investigate the enigmatic, post-depositional migration of methanesulfonic acid in polar ice. Our findings suggest that migration may be universal across coastal regions of Greenland and Antarctica, though it is mitigated at sites with higher accumulation and (or) lower impurity content. Records exhibiting severe migration may still be useful for inferring decadal and lower-frequency climate variability. Read more
Global consequences of afforestation and bioenergy cultivation on ecosystem service indicators Biogeosciences DOI 10.5194/bg-14-4829-2017 3 November 2017 Many climate change mitigation scenarios require negative emissions from land management. However, environmental side effects are often not considered. Here, we use projections of future land use from two land-use models as input to a vegetation model. We show that carbon removal via bioenergy production or forest maintenance and expansion affect a range of ecosystem functions. Largest impacts are found for crop production, nitrogen losses, and emissions of biogenic volatile organic compounds. Read more
Is there 1.5-million-year-old ice near Dome C, Antarctica? The Cryosphere DOI 10.5194/tc-11-2427-2017 2 November 2017 The oldest dated deep ice core drilled in Antarctica has been retrieved at EPICA Dome C (EDC), reaching ~ 800 000 years. Obtaining an older palaeoclimatic record from Antarctica is one of the greatest challenges of the ice core community. Here, we estimate the age of basal ice in the Dome C area. We find that old ice (> 1.5 Myr) likely exists in two regions a few tens of kilometres away from EDC:Little Dome C PatchandNorth Patch. Read more
The Palaeoclimate and Terrestrial Exoplanet Radiative Transfer Model Intercomparison Project (PALAEOTRIP): experimental design and protocols Geoscientific Model Development DOI 10.5194/gmd-10-3931-2017 1 November 2017 We provide the experimental designs and protocols for a community experiment to compare radiative transfer codes used for past climate on Earth, and for exoplanets. Read more
Impact of agricultural emission reductions on fine-particulate matter and public health Atmospheric Chemistry and Physics DOI 10.5194/acp-17-12813-2017 27 October 2017 This study shows that agricultural emissions are important for air quality and their reduction can effectively reduce the concentration of fine particles and their associated premature mortality. Therefore, emission control policies, especially in North America and Europe, should also involve strong ammonia emission decreases to optimally reduce fine-particle concentration. Read more
Vertical segregation among pathways mediating nitrogen loss (N2 and N2O production) across the oxygen gradient in a coastal upwelling ecosystem Biogeosciences DOI 10.5194/bg-14-4795-2017 26 October 2017 This investigation characterizes the variability of pathways involved in N loss in the water column over the continental shelf off central Chile during the development of the upwelling season. Our results highlight the links between several pathways involved in N removal, and considering the extreme variation in oxygen observed could help to understand the ecological and biogeochemical implications due to global warming when intensification and/or expansion of the oceanic OMZs are projected. Read more
Expansion of oil palm and other cash crops causes an increase of the land surface temperature in the Jambi province in Indonesia Biogeosciences DOI 10.5194/bg-14-4619-2017 25 October 2017 From the analysis of MODIS and Landsat satellite data of the Jambi province in Indonesia, this first study on the effects of oil palm expansion on the surface temperature in Indonesia shows shows a local and regional warming effect caused by the expansion of oil palm plantations and other cash or tree crops between 2000 and 2015. The observed warming effects may affect ecosystem services, reduce water availabilty in the dry period and increase the vulnerability to fires in the province. Read more