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High-latitude vegetation experience different temperatures than the ambient air temperature. While lacking a regional plant temperature product, we drove the dynamic ecosystem model, LPJ-GUESS, with widely used ERA5-land surface temperature (Tsurf, at radiative equilibrium) and air temperature to understand ecosystem process responses to these two temperatures. We show that tundra plants' growth i

Modern hydrological modeling frequently incorporates global remote sensing or reanalysis products for multivariate calibration. Although these datasets significantly contribute to model accuracy, the inherent uncertainties in the datasets and multivariate calibration present challenges in the modeling process. To address this issue, this study introduces an adaptive, process-wise fitting framework

Accurately representing and predicting hydrological processes in terrestrial ecosystems is crucial for understanding the impacts of global environmental change, particularly climate change. This doctoral thesis aims to advance the understanding of vegetation-hydrology interactions and provides new modelling approaches to enhance hydrological prediction abilities. The thesis is grounded in the eval

Fog makes a significant contribution to the hydrology of a wide range of important terrestrial ecosystems. The amount and frequency of fog immersion are affected by rapid ongoing anthropogenic changes but the impacts of these changes remain relatively poorly understood compared with changes in rainfall. Here, we present the design and performance of a novel experiment to actively manipulate low ly

Background: In the Sahel, one of the largest semi-arid areas in the world, pastoral livestock is the main source of protein for the local population. The quantification of herbaceous biomass in the Sahelian rangelands is of major importance since it provides food for the livestock. The main method used to monitor the biomass consists of cutting, drying, and weighting it. However, indirect methods

Drought is a multifaceted phenomenon driven by both natural climate fluctuations and human activities. Unlike traditional, slow-developing droughts, flash droughts (FDs) emerge suddenly and intensify rapidly, posing significant challenges for natural resource management. The lack of effective tools to quantify FDs exacerbates stakeholders' concerns, particularly due to the risks they pose to water

Increased global vegetation gross primary productivity (GPP) over the past decades has led to an enhanced terrestrial carbon sink, an important factor in mitigating global warming. However, the global spatiotemporal evolution of GPP trends is still under debate, largely limiting our understanding of the sustainability in terrestrial carbon sink. Here in this study, based on a dozen of long-term gl

The color of lakes is an essential indicator of the local ecological state, and the corresponding changes can reflect the physical and biochemical processes of lakes. However, worldwide changes in lake color and their drivers remain largely unknown. Here, we analyze the long-term color distributions and changes of 67,579 lakes worldwide from 1984 to 2021 by utilizing 32 million consistent satellit

This study investigates seasonal changes in near-surface wind speeds in the Arctic using the regional climate model (RCM) simulations with RCA4 driven by four global climate models (GCMs) CMIP5 under Representative Concentration Pathways (RCP) 4.5 and 8.5 scenarios. In addition, the RCM RCA-GUESS (RCA4 with interactive vegetation dynamics) is used to investigate the role of biogeophysical feedback

Nitrous oxide (N2O) is the most important stratospheric ozone-depleting agent based on current emissions and the third largest contributor to increased net radiative forcing. Increases in atmospheric N2O have been attributed primarily to enhanced soil N2O emissions. Critically, contributions from soils in the Northern High Latitudes (NHL, >50°N) remain poorly quantified despite their exposure to r

Ocean evaporation, represented by latent heat flux (LE), plays a crucial role in global precipitation patterns, water cycle dynamics, and energy exchange processes. However, existing bulk methods for quantifying ocean evaporation are associated with considerable uncertainties. The maximum entropy production (MEP) theory provides a novel framework for estimating surface heat fluxes, but its applica

Forestation is expected to play an significant role as a terrestrial carbon dioxide removal technology in low-emission scenarios by storing carbon in the biosphere, thereby changing the physical properties of the land surface. To represent land use change, including afforestation and reforestation (AR), Earth system models (ESM) that contribute to the Coupled Model Intercomparison Project Phase 6

Nutrients are the lifeblood of aquatic ecosystems, but not all nutrients are equally accessible to the organisms that depend on them. While traditional monitoring often tracks total or inorganic concentrations of carbon, nitrogen, and phosphorus, these measures do not reflect what microbial communities can actually use. This thesis explores that disconnect by investigating the bioavailability of k

Nitrogen (N) transformation processes by soil microbes account for significant nitrous oxide (N2O) emissions from natural ecosystems and cropland. However, understanding and quantifying global soil N2O emissions and their responses to changing environmental conditions remain challenging. Here, we implemented a soil nitrification–denitrification module into the dynamic vegetation model LPJ-GUESS to

Management of drained forested peatlands has important implications for carbon budgets, but contrasting views exist on its effects on climate. This study utilised the dynamic ecosystem model ForSAFE-Peat to simulate biogeochemical dynamics over two complete forest rotations (1951–2088) in a nutrient-rich drained peatland afforested with Norway spruce (Picea abies) in southwestern Sweden. Model sim

In recent decades, changes in vegetation phenology have exhibited a tight coupling with global warming. Mountain ecosystems are particularly susceptible to climate change, with high elevations warming faster than lower areas. The inconsistent rate of temperature change across elevations may lead to synchronization of phenological patterns, reducing the differences in phenology timing between high

The Sun’s energy is effectively limitless. While resources such as coal or gas are finite, if you are able to capture and use solar power it doesn’t prevent anyone else from also using as much sunshine as they need.Except that isn’t quite the full story. Beyond a certain size, solar farms become large enough to affect the weather around them and ultimately the climate as a whole. In our new resear