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Terrestrial ecosystems are the largest sink for carbon, and their ecosystem gross primary productivity (GPP) regulates variations in atmospheric carbon dioxide (CO2) concentrations. Current process-based ecosystem models used for estimating GPP are subject to large uncertainties due to poorly constrained parameter values. In this study, we implemented a global sensitivity analysis (GSA) on paramet

The emission of nitrous oxide (N2O) from agricultural soils to the atmosphere is a significant contributor to anthropogenic greenhouse gas emissions. The recycling of organic nitrogen (N) in manure and crop residues may result in spatiotemporal variability in N2O production and soil efflux which is difficult to capture by process-based models. We propose a multi-species, reactive transport model t

In response to rapid climate change and increasing human pressure, a wide variety of taxa have shifted their distribution in the past decades (range shift), with important consequences for ecosystem services and human health and economy. However, it is not yet clear whether most species will be able to track their favourable habitats or lag behind the climate signal (migration lag). Studying the p

The individual- and patch-based peatland-vegetation model LPJ-GUESS was employed to study past and future peatland carbon dynamics across the pan-Arctic. A substantial reduction in peatland sink capacity, expected under rapid global warming, has the potential to trigger important climate feedbacks.

Observed winter near-surface air temperature anomalies in the Northern Hemisphere have exhibited a warm Arctic-cold Eurasia (WACE) pattern with interdecadal variation in recent decades, but the exact mechanism behind WACE is still under debate. This study used reanalysis data and climate model simulations to investigate the interdecadal variability of the WACE pattern on a centennial scale, as wel

Data from four soil profiles studied through pollen and macroscopic charcoal analyses were used to identify specific palynological assemblages associated with a traditional land-use system documented in the Eastern Ligurian Apennines (NW Italy) between the 18th and early 20th century, concerning a cyclical use of grey alder plots for temporary cultivations involving to the use of controlled fire.

We present an evaluation of a nested high-resolution Goddard Earth Observing System (GEOS)-Chem chemistry transport model simulation of tropospheric chemistry over tropical South America. The model has been constrained with two isoprene emission inventories: (1) the canopy-scale Model of Emissions of Gases and Aerosols from Nature (MEGAN) and (2) a leaf-scale algorithm coupled to the Lund-Potsdam-

We investigated if coarse-resolution satellite data from the MODIS sensor can be used for regional monitoring of insect disturbances in Fennoscandia. A damage detection method based on z-scores of seasonal maximums of the 2-band Enhanced Vegetation Index (EVI2) was developed. Time-series smoothing was applied and Receiver Operating Characteristics graphs were used for optimisation. The method was

One of the major concerns regarding climate change in high latitudes is the potential feedback from greenhouse gases (GHG) being released from thawing peat soils. In this paper we show how vegetational patterns and associated GHG fluxes in subarctic palsa (peat mounds with a permanently frozen core) mires can be linked to climate, based on field observations from fifteen palsa sites distributed in

The African humid tropical biome constitutes the second largest rainforest region, significantly impacts global carbon cycling and climate, and has undergone major changes in functioning owing to climate and land-use change over the past century. We assess changes and trends in CO2 fluxes from 1901 to 2010 using nine land surface models forced with common driving data, and depict the inter-model v

Terrestrial carbon cycle models have incorporated increasingly more processes as a means to achieve more-realistic representations of ecosystem carbon cycling. Despite this, there are large across-model variations in the simulation and projection of carbon cycling. Several model intercomparison projects (MIPs), for example, the fifth phase of the Coupled Model Intercomparison Project (CMIP5) (hist

Soil carbon (C) is a critical component of Earth system models (ESMs), and its diverse representations are a major source of the large spread across models in the terrestrial C sink from the third to fifth assessment reports of the Intergovernmental Panel on Climate Change (IPCC). Improving soil C projections is of a high priority for Earth system modeling in the future IPCC and other assessments.

Understanding communication and signalling has long been strived for in studies of animal behaviour. Many songbirds have a variable and complex song, closely connected to territory defence and reproductive success. However, the quantification of such variable song is challenging. In this paper, we present a novel, automated method for detection and classification of syllables in birdsong. The meth

The climate sensitivity of carbon (C) cycling in Arctic terrestrial ecosystems is a major unknown in the Earth system. There is a lack of knowledge about the mechanisms that drive the interactions between photosynthesis, respiration, and changes in C stocks across full annual cycles in Arctic tundra. We use a calibrated and validated model (soil-plant-atmosphere; SPA) to estimate net ecosystem exc

Bryophytes play key roles in the ecological function of a number of major world biomes but remain understudied compared with vascular plants. Little is known about bryophyte responses to different aspects of predicted changes in moisture dynamics with climate change. In this study, CO 2 fluxes and photosynthetic light responses were measured within bryophyte mesocosms, being subjected to differe

The study has developed an interactive mission benefit analysis (MBA) tool that allows instantaneous evaluation of a range of potential mission designs. The designs are evaluated in terms of their constraint on carbon and water fluxes through calibration of a terrestrial bisphere model. The constraint is quantified by methematically rigorous uncertainty propagation in CCDAS. Applying the MBA tool,

Permafrost peatlands are biogeochemical hot spots in the Arctic as they store vast amounts of carbon. Permafrost thaw could release part of these long-term immobile carbon stocks as the greenhouse gases (GHGs) carbon dioxide (CO 2 ) and methane (CH 4 ) to the atmosphere, but how much, at which time-span and as which gaseous carbon species is still highly uncertain. Here we assess the effect of

Northern regions have received considerable attention not only because the effects of climate change are amplified at high latitudes but also because this region holds vast amounts of carbon (C) stored in permafrost. These carbon stocks are vulnerable to warming temperatures and increased permafrost thaw and the breakdown and release of soil C in the form of carbon dioxide (CO2) and methane (CH4).

There is growing evidence of ongoing changes in the statistics of intra-seasonal rainfall variability over large parts of the world. Changes in annual total rainfall may arise from shifts, either singly or in a combination, of distinctive intra-seasonal characteristics -i.e. rainfall frequency, rainfall intensity, and rainfall seasonality. Understanding how various ecosystems respond to the change

The decomposition of large stocks of soil organic carbon in thawing permafrost might depend on more than climate change-induced temperature increases: indirect effects of thawing via altered bacterial community structure (BCS) or rooting patterns are largely unexplored. We used a 10-year in situ permafrost thaw experiment and aerobic incubations to investigate alterations in BCS and potential resp