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Treeline encroachments and retractions can provide global-scale feedbacks to the climate system, and treeline dynamics are therefore of great relevance for understanding global climate variability. To assess the accuracy of long-term treeline simulations based on the generalized dynamic vegetation model LPJ-GUESS, we simulate European Arctic treeline dynamics over the past 9000 years and compare t

Carbon assimilation defined as the overall rate of fixation of carbon through the process of photosynthesis is central to the climate change research. The present study compares the two well-known algorithms in satellite based carbon assimilation estimation, the Vegetation Photosynthesis Model (VPM) and the MOD 17A2 GPP Model, over the tropical forest types in India for a period of two years (Sept

We evaluated the seasonality of CO2 fluxes simulated by nine terrestrial ecosystem models of the TRENDY project against (1) the seasonal cycle of gross primary production (GPP) and net ecosystem exchange (NEE) measured at flux tower sites over different biomes, (2) gridded monthly Model Tree Ensembles-estimated GPP (MTE-GPP) and MTE-NEE obtained by interpolating many flux tower measurements with a

We present a network of sites across Fennoscandia for optical sampling of vegetation properties relevant for phenology monitoring and satellite data calibration. The network currently consists of five sites, distributed along an N-S gradient through Sweden and Finland. Two sites are located in coniferous forests, one in a deciduous forest, and two on peatland. The instrumentation consists of dual-

Light sensors are increasingly used to monitor vegetation growing status by measuring reflectance or transmittance in multispectral or photosynthetically active radiation (PAR) bands. The measurements are then used to estimate vegetation indices or the fraction of absorbed PAR (FPAR) in a continuous and long-term manner and to serve as inputs to environmental monitoring and calibration/validation

Terrestrial ecosystems currently sequester about one third of anthropogenic CO 2 emissions each year, an important ecosystem service that dampens climate change. The future fate of this net uptake of CO 2 by land based ecosystems is highly uncertain. Most ecosystem models used to predict the future terrestrial carbon cycle share a common architecture, whereby carbon that enters the system as net p

Isoprene emission from Sphagnum species naturally growing at different positions above the water table were measured in a subarctic peatland and at monoliths from a temperate bog. Our objectives were to investigate (1) whether emission rates were species and/or moisture dependent, and (2) whether short-term temperature history had an influence on emission capacity. We expected greater emission cap

Övervakningen i vårt samhälle ökar allt mer och att så kan ske beror på hotet från terrorism. Stater vill genomföra åtgärder i konflikt med mänskliga rättigheter för att bekämpa hotet, organisationer vill skydda de mänskliga rättigheterna och människan vill både vara skyddad från terrorn och att sina rättigheter ska respekteras. Efter att Sveriges regelverk om lagringsskyldighet för tjänstelever

The emergence of large language models (LLMs) has made it easier than ever to create chatbots capable of generating human-like responses to user inputs. Moreover, improvements in text-to-speech and speech-to-text make it possible to converse with these systems, not just in text but also through speech. These improvements have led to an increase in chatbot applications across various contexts, such

Precise synchronization of paleoclimate records is essential for inferring the dynamics and past evolution of the climate system. For the last glacial period, the time scales of ice cores from the Greenland and Antarctic ice sheets have been synchronized by the use of cosmogenic radionuclides, atmospheric gas concentrations, and traces of large volcanic eruptions. Here we identify the sulfate depo

This chapter summarizes the processes that are responsible for cosmogenic radionuclide variations in ice cores and the results that can be inferred from these records. The chapter starts with the production in the atmosphere caused by the influx of galactic cosmic ray particles and its modulation by the solar and geomagnetic field. Subsequently, the geochemical behavior of cosmogenic radionuclides

Robo-Advisor is bringing a paradigm shift in the coming financial markets, changing the way individuals make investments. Based on algorithms and data, robo advisors helps in making informed financial decisions without human interventions. However, the enablers of robo advisors remain a grey area of research. Therefore, the presented study focused on exploring the enablers impacting robo advisor a

Rapid urbanization in Guangdong Province has severely impacted river systems due to limited understanding of the sustainability of river connectivity and functions. This study applies the Minimum Cumulative Resistance Model (MCRM) to quantify expansion costs of natural and social processes, with their difference defined as the River Ecological Sensitivity (RES) index. Higher RES values indicate th

Process-based biosphere models, which formulate biophysical ecosystem processes, provide a mechanistic framework for understanding terrestrial carbon dynamics. In contrast, data-driven approaches, e.g., upscaling eddy covariance (EC) fluxes using satellite observations and machine learning, offer empirical estimates. These complementary methods often diverge significantly, particularly in estimati

The Siljan-Orsasjön Basin in south-central Sweden hosts two prominent lakes. A 100 m deep channel extends approximately 52 km across the basin but does not form a continuous connection between the lakes today. Geophysical mapping, including multibeam bathymetry and sub-bottom profiling, revealed several landslide areas associated with the steep slopes of this channel and redistributed mass-wasted

Both the East Asian winter monsoon (EAWM) and El Niño (EN) activities are vital climate modes that regulate the Pacific hydrologic cycle. However, the Holocene interactions among the EAWM, EN activities, and tropical Pacific precipitation remain unclear due to the lack of appropriate EAWM proxies. Here, we present high-resolution grain size records from the East China Sea shelf along with a transi

Vegetation phenology obtained from time series of remote sensing data is relevant for a range of ecological applications. The freely available Sentinel-2 imagery at a 10 m spatial resolution with a ~ 5-day repeat cycle provides an opportunity to map vegetation phenology at an unprecedented fine spatial scale. To facilitate the production of a Europe-wide Copernicus Land Monitoring Sentinel-2 based

Climate warming leads to vast changes in the land cover types and plant biomass in the northern high-latitude regions. The overall trend is of shrubland and tree lines moving northwards, while changes in different land cover types and vegetation growth in response to climate change are largely unknown. Here, we selected land areas with latitudes higher than 50°N as the study area. We compared the