A5040617728- Climate variability and models
- Hydrology and Drought Analysis
- Meteorological Phenomena and Simulations
- Cryospheric studies and observations
- Climate change and permafrost
- Precipitation Measurement and Analysis
- Atmospheric and Environmental Gas Dynamics
- Arctic and Antarctic ice dynamics
- Arctic and Russian Policy Studies
- demographic modeling and climate adaptation
- Methane Hydrates and Related Phenomena
- Geophysics and Gravity Measurements
- Flood Risk Assessment and Management
- Indigenous Studies and Ecology
- Atmospheric Ozone and Climate
- Spatial and Panel Data Analysis
- Fire effects on ecosystems
- Sustainability and Ecological Systems Analysis
- Climate Change and Health Impacts
- Renewable Energy and Sustainability
- Tropical and Extratropical Cyclones Research
- Space Exploration and Technology
- Conservation, Biodiversity, and Resource Management
- Art, Aesthetics, and Perception
- European history and politics
Norwegian Meteorological Institute
2020-2024
University of Oslo
2020
Potsdam Institute for Climate Impact Research
2013-2014
University of Klagenfurt
2010
NSF National Center for Atmospheric Research
1998
The development of the first Australian C-band polarimetric/Doppler meteorological radar system (C-POL) is described. Motivated by need to obtain improved rainfall estimation and vertical profile hydrometeors, C-POL was developed jointly Bureau Meteorology (BOM), Commonwealth Scientific Industrial Research Organisation Australia, National Center for Atmospheric Research. based on a standard operational employed BOM but modified be capable transmitting linear horizontal polarizations...
Abstract Precipitation plays an important role in the Arctic hydrological cycle, affecting different areas like surface energy budget and mass balance of glaciers. Thus, accurate measurements precipitation are crucial for physical process studies, but gauge sparse subject to relocations several issues. From Svalbard, we analyze trends at six weather stations last 50–100 years by combining observation series adjusting inhomogeneities. For past 50 years, measured annual has increased 30%–45%....
There are few commonly used indicators that describe the state of Earth’s global hydrological cycle and here we propose three to capture how an increased greenhouse effect influences associated rainfall patterns. They are: i) 24-hr total rainfall, ii) surface area with daily precipitation, iii) mean precipitation intensity. With a recent progress in both satellite observations reanalyses, can now estimate provide new insights into intensity changes over time. Based on ERA5 reanalysis, find...
Abstract The cryosphere web portal maintained by the Norwegian Meteorological Institute (MET Norway), https://cryo.met.no , provides access to latest operational data and current state of sea ice, snow, permafrost in Norway, Arctic, Antarctic. We present addition this portal: monitoring at MET Norway methods for visualising real-time temperature data. temperatures are compared climatology generated from station’s record, including median, confidence intervals, extremes, trends. There...
Due to its location, old sewage system, and the channelling of rivers, Oslo is highly exposed urban flooding. Thus, it crucial provide relevant reliable information on extreme precipitation in planning design infrastructure. Intensity-Duration-Frequency (IDF) curves are a frequently used tool for that purpose. However, computational method IDF Norway was established over 45 years ago, has not been further developed since. In our study, we show current fitting Gumbel distribution highest...
Abstract. We present a framework for evaluating multi-model ensembles based on common empirical orthogonal functions (common EOFs) that emphasize salient features connected to spatio-temporal covariance structures embedded in large climate data volumes. This enables the extraction of most pronounced spatial patterns coherent variability within joint dataset and provides set weights each model terms principal components which refer exactly same covariance. In other words, EOFs provide means...
Abstract A simple formula for estimating approximate values of return levels sub-daily rainfall is presented and tested. It was derived from a combination mathematical principles, approximations fitted to 10 year taken intensity-duration-frequency (IDF) curves representing 14 sites in Oslo. The subsequently evaluated against IDF independent elsewhere Norway. Since it only needs 24 h rain gauge data as input, can provide estimates the used describe levels. In this respect, be considered means...
Abstract. Intensity–duration–frequency (IDF) statistics describing extreme rainfall intensities in Norway were analysed with the purpose of investigating how shape curves is influenced by geographical conditions and local climate characteristics. To this end, principal component analysis (PCA) was used to quantify salient information about IDF curves, a Bayesian linear regression study dependency shapes on climatological information. Our indicated that are both 24 h precipitation statistics....
Areal reduction factors (ARFs) convert a point estimate of extreme precipitation to an over spatial domain, and are commonly used in flood risk estimation. The fixed-area approach ARF estimation considers area certain size constructs the ratio extremes with same exceedance probability for areal average at representative location. In regions spare observation networks, estimates highly uncertain if based on rain gauge data only. We construct compare regional seasonal Norway using different...
This article provides a comprehensive insight into Germany’s transition to climate neutrality, bringing together the political framework of Climate Protection Act (CPA), funding strategy its key pillar,...
Precipitation on Svalbard can generally be linked to the atmospheric circulation in Northern Atlantic. Using an automated type classification, we show that weather statistics are well represented Max Planck Institute Earth System Model at base resolution (MPI-ESM-LR). For a future climate projection following Representative Concentration Pathway scenario RCP8.5, find only small changes statistics. However, convection permitting simulations with regional model from Consortium for Small-scale...
Purpose The Orange River is one of the largest river basins in southern Africa. Since it plays a crucial role region's ecology and economy, important to estimate future developments its hydrology. A necessary means this end are climate projections. This paper seeks address issue. Design/methodology/approach In work authors present projections obtained by two complementary methods; they use Statistical Analogue Re‐sampling Scheme (STARS) dynamical regional model (CCLM – COSMO Climate Mode)....
<p>Global warming is expected to alter the global hydrological cycle in addition higher temperatures, sea levels and melting ice. We present an analysis of how rainfall patterns have changed over period 1950-2020 based on ERA5 reanalysis, involving both aggregation 2D Haar wavelet analysis. Our results suggest that there been pronounced changes, such as increased activity rain events with a size less than 400 km. Such changes call for need hydro-climate indicators provide...
How well would your city weather a hurricane? Digitally “moving” past storms to new locations simulates the effects of extreme events on local infrastructure.
If the shape of mathematical curves describing local weather statistics are systematically influenced by large-scale conditions and geographical factors, then it may be possible to downscale this kind information directly. Such include probability density functions (pdfs) for daily temperature/precipitation or intensity-duration-frequency (IDF) estimating return values intense sub-daily rainfall. Downscaling such referred as ‘downscaling climate’ if we regard...
We present an interactive climate atlas providing visualisations of future regional projections temperature and precipitation in northern Europe from multiple sources. It is based on results both empirical-statistical dynamical downscaling multi-model ensembles CMIP5 CMIP6 including several emission scenarios. Displayed alongside each other, the projected change estimated different model can be compared contrasted. The comparison useful to evaluate robustness information influence...
In August 2023, the extreme weather event “Hans” moved into Scandinavia from southeast, bringing large amounts of rainfall. It led to large-scale floods, a number landslides and forced evacuations across parts southeastern Norway, ended up costing more than 150 million Euros.In water poses largest physical climate risk, adaptation prepare for such events is crucial. Successful relies on accurate design values any location, area (such as catchment), well future climate.We...