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This study maps agriculture’s vulnerability to drought in the European pre-Alpine regions of Thurgau (CH) and Podravska (SI). We combine region-specific knowlegde supported with quantitative data: experts of the study regions, far apart, identified few common but more region-specific factors that we integrated in two vulnerability 'scenarios'. We highlight the benefits of the participatory approach improving the quantitative results and closing the gap between science and practictioners.

Applying DLM, we confirm near-global ozone recovery [55N–55S] in the mesosphere, upper and middle stratosphere, as well as a steady increase in tropospheric ozone. We also show that modern CCMs, such as SOCOLv4, still cannot properly reproduce the observed trends in extratropical low stratospheric ozone, exhibiting weak and non-significant trends. Nevertheless, the obtained pattern of ozone trends in SOCOLv4 is generally consistent with observations and reanalysis data sets.

We present results from the Met Office Unified Model (UM) to study the dry Martian climate. We describe our model setup conditions and run two scenarios, one with dust that interacts with the environment and it does not. We compare both scenarios to results from an existing Mars climate model, the Planetary Climate Model. We find good agreement in winds and air temperatures, but dust amounts differ between models. This study highlights the importance of using the UM for future Mars research.

Collisional fragmentation of asteroids, comets and meteoroids result in the formation of dust in the solar system. The dust distribution is however uncharted and the role of dust in the solar system is largely unknown. At present, the solar system is explored by the Solar Orbiter spacecraft. We present a novel method, based on artificial intelligence, that can be used for detecting when dust particles impact the Solar Orbiter with high accuracy, making it possible to study the dust distribution.

Easterly winds encircle Antarctica, moving sea ice and helping drive ocean currents which shield ice shelves from warmer waters. Our most complete picture of how these winds behave comes from reanalysis datasets. In this paper we use satellite data, surface measurements and weather balloons to test how realistic recent reanalysis estimates are. The winds are generally accurate, especially in the most recent of the datasets, but important short-term variations are often misrepresented.

Climate change is causing extensive permafrost degradation and nutrient releases into rivers with great ecological impacts on the Arctic Ocean. We focused on nitrogen (N) release from this degradation and associated cycling using N isotopes, an understudied area. Many N species are released at degradation sites with exchanges between species. N inputs from permafrost degradation and seasonal river nitrogen trends were identified using isotopes, helping to predict climate change impacts.

It is not known if the Last Interglacial (LIG) experienced Arctic summers that were sea ice-free: models show a wide spread in LIG Arctic temperature and sea ice results. Evaluation against sea ice markers is hampered by too few observations. Here, assessment of 11 climate model simulations against summer temperatures shows that the most skilful models have a 77–79 % reduction in LIG sea ice. A LIG area of sea ice (1.3 mill. km²) indicates a likely mix of ice-free and near ice-free LIG summers.

This contribution is focused on the accurate measurement of U and Th by wet chemistry and laser ablation to improve the (U-Th)/He dating of magnetite and spinel. The low U-Th content and the lack of specific U-Th standards limit significantly the accuracy of (U-Th)/He dating. Obtained U and Th results on natural and synthetic magnetite and aluminous spinel samples analyzed by both extraction methods, have important implications for the (U-Th)/He method and dates interpretation.

This study aims to analyse the changes of the vertical structure of the ocean during upwelling and the role of climate patterns in the Canary Current (25–35° N) for a period of 25 years (1993–2017). Ocean mixing is enhanced during upwelling events and extents deeper (shallower) in the winters of positive (negative) North Atlantic Oscillation. It is enhanced during coupled, opposite phases of the East Atlantic pattern suggesting stronger upwelling activity in dependence of climate patterns.

The objective of this study is to reconstruct the climatic variability in Haiti during the last millennium using mineralogical and geochemical composition. We also seek to understand climate mechanisms and modes that could explain this variability. The results showed that Haiti has experienced long progressively drier periods over the past millennium. The rainy or dry periods in Haiti are linked to the average changes in the temperature of the oceans: Atlantic and Pacific, through oscillations.

We present new tools in the Landscape Evolution Model “Badlands” to simulate ¹⁰Be production, erosion and transport. These tools are applied to a source-to-sink system in the SW French Alps where the model is calibrated. We propose a model that fits river incision rates and ¹⁰Be concentrations in sediments, and we show that ¹⁰Be in marine sediments is a signal with multiple contributions that cannot be easily interpreted.

Long-term observations of snow are well suited as indicators of climate change, but our current knowledge of snow depth trends is based almost entirely on non-homogenised data, which shows only a veiled picture of the real trends due to inhomogeneities. We compare the impact of homogenization methods on snow indices using Swiss time series between 1961–2021 and present ways to improve the results. E.g., the adjustments removed all positive trends for snow days, especially for stations >1500 m.

By monitoring the concentration and Δ¹⁷O of stream nitrate in three forested streams, the new nitrogen saturation index of forested catchments (M_atm / D_atm ratio) was estimated. We found that (1) the unprocessed atmospheric nitrate in our studied forested stream (FK1 catchment) was the highest ever reported in forested streams, (2) the M_atm / D_atm ratio can be used as a robust index for evaluating nitrogen saturation in forested catchments as the M_atm / D_atm ratio is independent of the precipitation.

We measured volatile and intermediate-volatility gases and semi-volatile gas- and particle-phase compounds in the atmosphere during an 11-day period in a Bay Area suburb. We separated compounds based on variability in time to arrive at 13 distinct sources. Some compounds emitted from plants are found in greater quantities as fragrance compounds in consumer products. The wide volatility range of these measurements enables the construction of more complete source profiles.

We describe the development of the first large-scale ice sheet model that accounts for stochasticity in a range of processes. Stochasticity allows to represent the impacts of inherently uncertain processes on ice sheets. This includes climatic uncertainty, as the climate is inherently chaotic. Furthermore, stochastic capabilities also encompass poorly constrained glaciological processes that display strong variability at fine spatiotemporal scales. We present the model and test experiments.

The increase in ocean mass due to land ice melting is responsible for about two thirds of the global mean sea level rise. The ocean mass variations are monitored by GRACE and GRACE Follow-On gravimetry satellites that faced instrumental issues over the last few years. In this work, we assess the robustness of these data by comparing the ocean mass gravimetry estimates to independent observations (other satellite observations, oceanographic measurements and land ice and water models).

We studied the long-term mean flow through the Marsdiep tidal inlet in the Dutch Wadden Sea. We found that this flow, which is important for sediment, salt and nutrient balances, is reversing from net outflow to inflow. We relate this to changes in tides in the North Sea, caused by increased stratification in response to global warming. Hence, we expect permanent inflow conditions within a decade, with potential effects on the sediment balance and the ecosystem of this World Heritage site.

In this work, we propose a flexible framework to generate and interact with geological models using explicit surface representations. The essence of the work lies in the determination of the flexible control mesh, topologically similar to the main geological structure, watertight and controllable with few number of control points to manage the geological structures. We exploited subdivision surface method in our work, which is commonly used in animation and gaming industry.

Phenomenological models may be impressive in reproducing empirical time series but this is not sufficient to claim physical similarity with nature until comparison of similarity parameters is performed. We illustrated such a process of diagnostics of physical similarity by comparing a phenomenological dynamical paleoclimate model with a more physically explicit dynamical model.

Smile effect (an effect in which a shift in the center wavelength appears as a distortion in the spectral image) was detected during our recent work. To evaluate how it affects the cloud retrieval product, we did a simulation of MSI forward radiation, then evaluated the error in simulated scenes from a global cloud system resolving model and a satellite simulator. Our results indicated that the error from the smile effect was generally small and could be seen as negligible for oceanic scenes.

Our manuscript presents an alternative approach for generating high-resolution precipitation maps based on the non-linear combination of the complete set of variables of the numerical weather predictions. This process combines the super-resolution task with the bias correction in a single step, generating high-resolution corrected precipitation maps with 3 hour lead time. We used using deep learning algorithms to combine the input information and increase the accuracy of the precipitation maps.

Using a small research vessel based out of Cambridge Bay in the Kitikmeot Sea (Canadian Arctic Archipelago), we were able to make measurements of surface ocean pCO₂ shortly after sea ice breakup for four consecutive years. We compare our measurements to previous underway measurements and the two ongoing ocean carbon observatories in the region. We identify high inter annual variability and a potential bias in previous estimates due to lower pCO₂ in bays and inlets.

This work investigates the potential value of using fine-scale meteorological ensembles to represent the inherent meteorological uncertainties in atmospheric dispersion models outputs. Probabilistic scores were used to evaluate the probabilistic performance of dispersion ensembles, using an original data set of new continuous Krypton-85 air concentration measurements and a well-known source term. The results show that the ensemble dispersion simulations performs better than deterministic ones.

CFC-11 and CFC-12, which are classified as ozone depleting substances, also have high global warming potentials. This paper describes obtaining the CFC-11 and CFC-12 vertical profiles and total columns from the solar spectra based on ground-based Fourier transform infrared spectroscopy at Hefei, China. The seasonal variation and annual trend of the two gases are analyzed, and then the data are compared with other independent datasets.

Mesoscale eddies are ubiquitous turbulent structures in the ocean, influencing the upper mixed layer. The mixed layer is the ocean surface layer mixed through air-sea exchanges. Using Argo profiling floats inside large Mediterranean anticyclone, we investigate the induced winter mixed layer depth anomalies. Mixed layer depth was observed to be greatly influenced by eddy preexisting subsurface structure to which it possibly connects, and can also create double-core anticyclones.

The long-term comparison between observed and simulated outgoing longwave radiances represents a strict test to evaluate climate model performance. In this work, 9 years of synthetic spectrally resolved radiances simulated on-line on the basis of the atmospheric fields predicted by the EC-Earth GCM (version 3.3.3) in clear-sky conditions are compared to a IASI spectral radiance climatology in order to detect model biases in temperature and humidity at different atmospheric levels.

An analytical approach for calculating the theoretical tidal gravity of a three-dimensional Earth is developed. The current study determines the effects of lateral inhomogeneity and compares the results with those of other factors. The rotation and ellipticity should be the most dominant contributor, whose influence may be three times larger than that of the lateral inhomogeneity. Ocean tide loading is a moderate factor, and the lateral inhomogeneity is the least but non-neglected factor.

Sudden releases of meltwater from glacier-dammed lakes can influence ice flow, cause flooding hazards and landscape changes. This study presents a record of 14 drainages from 2007–2021 from a lake in West Greenland. The time series reveals how the lake fluctuates between releasing large and small amounts of drainage water which is caused by a weakening of the damming glacier following the large events. We also find a shift in the water drainage route which increases the risk of flooding hazards.

There is confusion in the literature on interactions of dissolved phosphate and sulphate with the alkalinity of seawater. These do play a minor role in the titration to determine alkalinity. However, a perceived biological role of phosphate and sulphate has been suggested in the value of Oceanic Alkalinity. We think this is mistaken. Some other minor issues additionally have led to confusion on the exact description of Alkalinity. We treat those against a theoretical and empirical background.

This study introduces an improved method of the Globally Resolved Energy Balance Model by the Bayes network. Starting from the climate elements relationship included in the GREB model, we reconstruct the model by the Bayes network to solve the problem of low model accuracy due to the inability to use observed data for dynamic correction of model parameters. The results show that the improved model has higher average accuracy and lower spatial variability.

This study is aims to analyze seasonal and long-term trend of meteorological drought trends under climate change. We merge tree-ring proxy with instrumental datasets to understand multi-centennial trends. We develop an approach for temporal downscaling from bi-annual time series to monthly scale, and develop a model for bias correction and trend analysis across all datasets. The model was applied to 14 sites in US, and found regions with recent wetting/drying trends and rapid seasonal shifts.

Black carbon (BC) is often assumed to be spherical in shape, causing uncertainties in its optical properties when modeled. This study investigates different modeling techniques for the optical properties of BC by comparing them to laboratory measurements. We provide experimental support for emphasizing the use of an appropriate size representation (polydisperse size method) and morphological representation (aggregate morphology) for optical modeling and parametrization scheme development of BC.

Natural climate variability plays an important role in the discussion of past and future climate change. Here we study centennial temperature variability and the role of large-scale ocean circulation variability using different climate models, geological reconstructions and temperature observations. Unfortunately, uncertainties in models and geological reconstructions are such that more research is needed before we can describe the characteristics of natural centennial temperature variability.

Chemical reactions in river sediments influence how clean the water is and how much greenhouse gas comes out of a river. Our study investigates why some sediments have higher rates of chemical reactions than others. We find that to achieve high rates, sediments need to have two things: only a few different kinds of molecules, but a lot of them. This result spans about 80 rivers such that it could be a general rule helpful for predicting the future of rivers and our planet.

The majority of river studies focuses on headwater or floodplain systems, while often neglecting intermediate river segments. Our study on the subalpine Sihl River bridges the gap between streams and lowlands and demonstrates that moderately steep river segments are areas of significant instream transformation, modulating the export of organic carbon over short distances.

The behaviour of natural systems is now very often represented through mathematical models. These models represent our understanding of how the nature works. Of course, the nature doesn't care about our understanding. Since our understanding is not perfect, evaluating models is challenging and there are uncertainties. This manuscript illustrates this uncertainty for land models and argues that evaluating models in the light of uncertainty in various components provides useful information.

As the transition zone between the Tibetan Plateau and the arid region, the Qilian Mountains are important ecological barriers and source regions of inland rivers in northwest China. In recent decades, drastic changes in the cryosphere have had a significant impact on the quantity and formation process of water resources in the Qilian Mountains. the mountain runoff of Qilian Mountains mainly comes from the cryosphere belt, which contributes to approximately About eighty percent runoff.

While the national ambient air quality standard of ozone is based on the 3-year average of the 4^th highest 8-hour maximum (MDA8) ozone concentrations, these predicted extreme values using numerical methods are always biased low. We built 4 computational models (GAM, MARS, Random Forest & SVR) to predict the 4^th highest MDA8 ozone in Southern California using precursor emissions, meteorology, and climatological patterns. All models presented acceptable performance with GAM being the best.

Heat flux is one of the major factors leading to ocean climate change under global warming. In this study, we quantitatively evaluate the impacts of the magnitude change of heat-flux perturbations over North Atlantic (NA) region on the ocean climate change. We found the changes in Atlantic Meridional Overturning Circulation (AMOC) and added ocean heat uptake over NA were almost linearly related to the heat flux over NA, while the changes in redistributed ocean heat uptake over NA were not.

This work develops a novel lightning data assimilation (LDA) technique to make use of Meteosat Third Generation (MTG) Lightning Imager (LI) data in a regional, convection-permitting numerical weather prediction model. The approach combines statistical Bayesian and 3-dimensional variational methods. Our LDA can promote missing convection and suppress spurious convection in the initial state of the model, and has similar skill to the operational radar data assimilation for rainfall forecasts.

The present study addresses the soil information gap in tropical seagrass meadows. The different geological and bioclimatic settings caused a relevant soil diversity. Contrasting geochemical conditions promote different intensities of soil processes. Seagrass soils from the NE semiarid coast are marked by a more intense sulfidization. Understanding soil processes may help in the sustainable management of seagrasses.

Mollusk shells are valuable recorders of climate and environmental changes of the past down to a daily resolution. To explore this potential, we measured changes in the composition of shells of two types of bivalves recorded at the hourly scale: The king scallop Pecten maximus, and giant clams (Tridacna) that have engage in photosymbiosis. We find that photosymbiosis produces more day-night fluctuation in shell chemistry, but that most of the variation is not periodic, perhaps recording weather.

Anthropogenic climate change will influence marine phytoplankton over the coming century. Here, we quantify the influence of anthropogenic climate change on marine phytoplankton variance using an Earth System Model ensemble, identifying a decline in global phytoplankton biomass variance with warming. Our results suggest that climate mitigation efforts that account for marine phytoplankton changes should also consider changes in phytoplankton variance driven by anthropogenic warming.

Altimetry satellite are essential to monitor and understand sea level evolution around the world with rates accuracy of mm/year. But these systems must also be qualified and controlled, especially approaching the coast. Using long-term sea level time series from Noumea tide gauge (New-Caledonia) and in situ data collected during the GEOCEAN-NC campaign, we propose a method to re-analyse about twenty years of altimetry observations and re-address the question of sea level evolution in the lagoon.

I use observations to establish that changing river flows were an important contributor to coastal sea-level changes in the Río de la Plata of South America during the past century.

The early 19^th century was the coldest period over the past 500 years, when strong tropical volcanic events and a solar minimum coincided. This study quantifies potential surface cooling from the solar and volcanic forcing in the early 19^th century with large ensemble simulations and identifies the regions that their impacts cannot be simply additive. The cooling perspective of Arctic Amplification exists in both solar and post-volcano period with the albedo feedback as the main contribution.

It is always difficult to quantify seismic hazard for a region with a complex fault system. Thus, we proposed a physics-based model and confirm its credibility through fitting a case of an Indonesian earthquake. Our model could be further applied for evaluating potential seismic hazard in strong ground shaking and fault displacement.

Experiments we conducted show that the carbonate inventory of Aegean seawater is in part not in exchange with atmospheric CO₂. This "background" reservoir makes up around 78 % of the total carbon in Aegean Seawater. This means that only 22 % of the dissolved inorganic carbon is in equilibrium with the atmosphere and is thus able to buffer anthropogenic CO₂. Based on our results it can be calculated that the buffer capacity for CO₂ in Aegean seawater will be reduced by 50 % by the year 2100.

We first present a novel method of monitoring the UHI intensity using GNSS data. We overcomes two major challenges in the algorithm development. The first challenge is the determination of the GNSS tomographic top grid height, and the second challenge is the estimation of temperature from wet refractivity. The result shows that the proposed algorithm can achieve an accuracy of 1.2 K at a 95 % confidence level.

The particle size and chemical composition of bioaerosol were analyzed based on single particle aerosol mass spectrometer. Fungal aerosol of 10 μm was measured for the first time and the characteristic spectrum of bioaerosol was updated. The ion peak ratio method can distinguish bioaerosols from interferers by 97 %. The factors influencing the differentiation of bioaerosols are also discussed. Single particle mass spectrometry can be a new method for real-time identification of bioaerosols.