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Climate-herbivory interactions have been largely debated vis-à-vis ecosystem carbon sequestration. However, invertebrate herbivores also modify emissions of plant biogenic volatile organic compounds (BVOCs). Over the shorter term, they do this by the induction of de novo synthesis of a plethora of compounds; but invertebrates also affect the relative proportions of constitutively BVOCs-emitting pl
We have incorporated a semi-mechanistic isoprene emission module into the JULES land-surface scheme, as a first step towards a modelling tool that can be applied for studies of vegetation - atmospheric chemistry interactions, including chemistry-climate feedbacks. Here, we evaluate the coupled model against local above-canopy isoprene emission flux measurements from six flux tower sites as well as
Through rapid reactions with ozone, which can initiate the formation of secondary organic aerosols, the emission of sesquiterpenes from vegetation in Amazonia may have significant impacts on tropospheric chemistry and climate. Little is known, however, about sesquiterpene emissions, transport, and chemistry within plant canopies owing to analytical difficulties stemming from very low ambient conce
The simulation of current and projected wildfires is essential for predicting crucial aspects of vegetation patterns, biogeochemical cycling as well as pyrogenic emissions across the African continent. This study uses a data-driven approach to parameterize two burned area models applicable to dynamic vegetation models (DVMs) and Earth system models (ESMs). We restricted our analysis to variables f
In September 2012, Arctic sea-ice extent plummeted to a new record low: two times lower than the 1979-2000 average. Often, record lows in sea-ice cover are hailed as an example of climate change impacts in the Arctic. Less apparent, however, are the implications of reduced sea-ice cover in the Arctic Ocean for marine-atmosphere CO2 exchange. Sea-ice decline has been connected to increasing air tem
The LPJ-GUESS dynamic vegetation model uniquely combines an individual-and patch-based representation of vegetation dynamics with ecosystem biogeochemical cycling from regional to global scales. We present an updated version that includes plant and soil N dynamics, analysing the implications of accounting for C-N interactions on predictions and performance of the model. Stand structural dynamics a
The land and ocean absorb on average just over half of the anthropogenic emissions of carbon dioxide (CO2) every year. These CO2 "sinks" are modulated by climate change and variability. Here we use a suite of nine dynamic global vegetation models (DGVMs) and four ocean biogeochemical general circulation models (OBGCMs) to estimate trends driven by global and regional climate and atmospheric CO2 in
The capacity for volatile isoprenoid production under standardized environmental conditions at a certain time (E-S, the emission factor) is a key characteristic in constructing isoprenoid emission inventories. However, there is large variation in published E-S estimates for any given species partly driven by dynamic modifications in E-S due to acclimation and stress responses. Here we review addit
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
Exchange of non-CO2 trace gases between the land surface and the atmosphere plays an important role in atmospheric chemistry and climate. Recent studies have highlighted its importance for interpretation of glacial-interglacial ice-core records, the simulation of the pre-industrial and present atmosphere, and the potential for large climate-chemistry and climate-aerosol feedbacks in the coming cen
The measured net ecosystem exchange (NEE) of CO2 between the ecosystem and the atmosphere reflects the balance between gross CO2 assimilation [gross primary production (GPP)] and ecosystem respiration (R-eco). For understanding the mechanistic responses of ecosystem processes to environmental change it is important to separate these two flux components. Two approaches are conventionally used: (1)
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This paper discusses the effects of vegetation cover and soil parameters on the climate change projections of a regional climate model over the Arctic domain. Different setups of the land surface model of the regional climate model HIRHAM were realized to analyze differences in the atmospheric circulation caused by (1) the incorporation of freezing/thawing of soil moisture, (2) the consideration o
Syftet med studien är att undersöka kundlojalitet på lågengagemangsmarknader och därigenom förstå och redogöra för om företag som erbjuder lågengagemangsprodukter kan uppnå sann kundlojalitet utifrån sitt produkt- och serviceerbjudande och i så fall hur de detta kan göras. Denna abduktiva studie är utformad utifrån en kvalitativ ansats med inslag av kvantitativ metod i form av fokusgrupper, observThe purpose of this study is to analyze the customer loyalty that exists in a low-involvement market. The study will enable an understanding for if companies selling low-involvement products can attain true customer loyalty through the product and service offered, and if so, how this can be accomplished. This abductive study is using a qualitative framework with elements of a quantitative method b
The Arctic is rapidly transitioning toward a seasonal sea ice-free state, perhaps one of the most apparent examples of climate change in the world. This dramatic change has numerous consequences, including a large increase in air temperatures, which in turn may affect terrestrial methane emissions. Nonetheless, terrestrial and marine environments are seldom jointly analyzed. By comparing satellite
An activity-based vocabulary for Voice Output Communication Aids (VOCAs) was designed and evaluated through a user-centred, iterative design process, using expressions from the Gothenburg Spoken Language Corpus as well as other recorded, natural conversations. The growth and development of the vocabulary, called Phrases, was closely linked to its evaluation. The iterative design process included p
Climate warming in the Swedish sub-Arctic since 2000 has reached a level at which statistical analysis shows for the first time that current warming has exceeded that in the late 1930' s and early 1940' s, and has significantly crossed the 0 degrees C mean annual temperature threshold which causes many cryospheric and ecological impacts. The accelerating temperature increase trend has driven simil
