Irene Brox Nilsen

• Huang, Shaochun; Wong, Wai Kwok; Dobler, Andreas; Bakke, Sigrid Jørgensen; Beldring, Stein & Haddeland, Ingjerd [Show all 14 contributors for this article] (2026). An improved modelling chain for bias-adjusted high-resolution climate and hydrological projections for Norway. Geoscientific Model Development. ISSN 1991-959X. 19(10), p. 4567–4599. doi: 10.5194/gmd-19-4567-2026. Full text in Research Archive Show summary

  About every 10 years, the Norwegian Centre for Climate Services publishes a national climate assessment report, presenting the updated historical climate change and climate projections towards the end of this century. This paper documents the model experiment used to generate high-resolution climate and hydrological projections for the new climate assessment report published in October 2025. The model experiment follows the standard modelling chain for hydrological impact assessment, i.e., climate model selection – downscaling and bias adjustment – hydrological modelling. However, compared with the model experiment for the climate assessment report published in 2015, all modelling components have been improved in terms of data availability, data quality and methodology. Specifically, a large climate model ensemble was available and new criteria were developed to select tailored climate projections for Norway. Two bias-adjustment methods (one univariate and one multivariate) were applied to account for the uncertainty of method choice. The hydrological modelling was improved by implementing a physically-based Penman–Monteith method for evaporation and a glacier model accounting for glacier retreat under climate change scenarios. Besides model description, this paper elaborates the effects of different bias-adjustment methods and the contribution of climate models and bias-adjustment methods to the uncertainty of climate and hydrological projections under the RCP4.5 scenario as examples. The results show that the two bias-adjustment methods can contribute larger uncertainty to seasonal projections than climate models. The multivariate bias-adjustment method improves hydrological simulations, especially in the reference period, but cannot conserve climate change signals of the original climate projections. The dataset generated by the presented modelling chain provides the most updated, comprehensive and detailed hydrometeorological projections for mainland Norway, serving as a knowledge base for climate change adaptation to decision makers at various administrative levels in Norway.

• Nilsen, Irene Brox; Hanssen-Bauer, Inger; Dyrrdal, Anita Verpe; Hisdal, Hege; Lawrence, Deborah & Haddeland, Ingjerd [Show all 7 contributors for this article] (2022). From Climate Model Output to Actionable Climate Information in Norway. Frontiers in Climate. 4. doi: 10.3389/fclim.2022.866563. Full text in Research Archive Show summary

  The Norwegian Centre for Climate Services (NCCS) has developed a production chain for climate information with the aim of delivering a knowledge base for climate change adaptation suitable for use by planners at various administrative levels in Norway. This process consists of two main steps: First, climate and hydrological projections are produced at a local scale (1 × 1 km resolution) using available results from global and regional climate models (GCMs and RCMs). In a second step, climate factsheets with abridged information relevant for individual counties in Norway have been co-produced with users and county authorities. Projections were produced by using a climate–hydrological modeling chain driven by downscaled simulations from 10 GCM–RCM combinations and two climate scenarios in which temperature and precipitation were first downscaled and bias-adjusted to a 1 × 1 km resolution. Bias-adjustment was necessary, partly due to biases in the RCMs. These results were published in the Norwegian climate assessment report “Climate in Norway 2100.” The results have then been disseminated through various formats, such as reports, dataportals, visualizations and factsheets (available at https://klimaservicesenter.no/ ). NCCS has issued climate factsheets for 17 counties in Norway and Svalbard. The county-wise climate factsheets have become the most extensive product issued by NCCS. A challenge when developing information about climate change for use in adaptation is the issue of uncertainty, and the trade-off between robustness vs. precision in the numerical values given should guide the dissemination of climate information. Based on our experiences, we also recommend that climate information is developed in collaboration with users because this ensures that it will be understood by a wider audience. Most climate-related challenges for infrastructure are related to extreme events. For technical applications in Norway, climate change allowances are now available for heavy precipitation, floods, and storm surges as a tool for design analyses of buildings and infrastructure. This paper describes the production chain for the presently available climate projections following the release of IPCC AR5 (CMIP5), our experiences of the dissemination process, as well as our plans for further development of the next national climate assessment report based on IPCC AR6 (CMIP6).

• Rizzi, Jonathan; Nilsen, Irene Brox; Stagge, James Howard; Gisnås, Kjersti Gleditsch & Tallaksen, Lena M. (2018). Five decades of warming: impacts on snow cover in Norway. Hydrology Research. ISSN 1998-9563. 49(3), p. 670–688. doi: 10.2166/nh.2017.051. Full text in Research Archive Show summary

  Northern latitudes are experiencing faster warming than other regions in the world, which is partly explained by the snow albedo feedback. In Norway, mean temperatures have been increasing since the 1990s, with 2014 being the warmest year on record, 2.2 °C above normal (1961–1990). At the same time, a concurrent reduction in the land area covered by snow has been reported. In this study, we present a detailed spatial and temporal (monthly and seasonal) analysis of trends and changes in snow indices based on a high resolution (1 km) gridded hydro-meteorological dataset for Norway (seNorge). During the period 1961–2010, snow cover extent (SCE) was found to decrease, notably at the end of the snow season, with a corresponding decrease in snow water equivalent except at high elevations. SCE for all Norway decreased by more than 20,000 km2 (6% of the land area) between the periods 1961–1990 and 1981–2010, mainly north of 63° N. Overall, air temperature increased in all seasons, with the highest increase in spring (particularly in April) and winter. Mean monthly air temperatures were significantly correlated with the monthly SCE, suggesting a positive land–atmosphere feedback enhancing warming in winter and spring.

• Nilsen, Irene Brox; Stagge, James Howard & Tallaksen, Lena M. (2016). A probabilistic approach for attributing temperature changes to synoptic type frequency. International Journal of Climatology. ISSN 0899-8418. 37(6), p. 2990–3002. doi: 10.1002/joc.4894. Full text in Research Archive Show summary

  To understand the cause of regional temperature change, it is common to separate the temperature change signal into changes in atmospheric synoptic circulation and other factors, so-called within-type changes. In this study, we suggest a novel probabilistic approach that allows detection of months and regions where temperature changes can mainly be attributed to changes in synoptic circulation and where within-type changes also play a role. By combining resampling with a Monte Carlo test, we assess the likelihood that the observed warming can be explained by synoptic circulation changes alone. This method is applicable for any variable, and in any region of the world. We applied it to an example case using gridded WATCH Forcing Data ERA-Interim (WFDEI) temperature data and synoptic types derived from the SynopVis Grosswetterlagen catalogue (1981–2010). For this European example, the most widespread warming was found in summer, with up to 60% of the land area experiencing signicant warming during August, notably in Eastern and Northern Europe. In spring and autumn, this area was reduced to 10–30%. In December and January, only about 5% of the land area experienced signicant warming, most pronounced in northern Scandinavia. The probabilistic approach revealed that changes in synoptic circulation c ould not account for all the observed (WFDEI) warming, with the exception of regions in southeastern Europe in February and Western Europe in May. Signicant warming in other months and regions, such as the large-scale warming in April, June, July, August, and November, must also be caused by other factors. Within-type changes were conrmed for the Black Sea region in November, where the magnitude of a widespread temperature trend was strongest. This European example contributes to an improved understanding of the causes of recent temperature change by assessing the relative role of synoptic circulation changes and within-type changes on regional-scale warming.

• Nilsen, Irene Brox; Fleig, Anne K.; Tallaksen, Lena M. & Hisdal, Hege (2014). Recent trends in monthly temperature and precipitation patterns in Europe. IAHS-AISH publication. ISSN 0144-7815. 363, p. 132–137. Full text in Research Archive

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• Nilsen, Irene Brox (2025). Historiske endringer i avrenning i Norge : bakgrunnsrapport til rapporten Klima i Norge. Full text in Research Archive Show summary

  Her sammenlignes ulike datasett brukt til kapitlet om historisk avrenning i Klima i Norge og begrunner valget av distHBV framfor datasettene Avrenningskartet og Totalavrenning som referansedatasett for endringer i avrenning for historisk periode.

• Nilsen, Irene Brox; Isaksen, Ketil; Svello, Sunniva Nordeide; Hanssen-Bauer, Inger & Bakke, Sigrid Jørgensen (2025). Observerte langtidstrender i snøforhold i Norge. Full text in Research Archive Show summary

  Her beskrives historiske endringer i snøforhold. Siden målingene av snødybde startet på tidlig 1900-tall, er det observert kortere ​snødekkesesong​ og mindre snødybde i lavereliggende og midlere høyder. Flere steder har skisesongen blitt 4–6 uker kortere, siden målingene startet (målestart varierer fra måleserie til måleserie). Snømengdene har også blitt redusert ved de fleste måleseriene. Unntaket er enkelte måleserier i høyereliggende områder.

• Dalen, Lars Sandved; Eisner, Stephanie & Nilsen, Irene Brox (2023). Varmere vær gir flere varmekjære trær - Nibio. [Internet]. nibio.no. Full text in Research Archive Show summary

  Blir det kaldt kler vi på oss, blir det varmt tar vi klærne av. Men hva med trærne? Hva gjør de når klimaet endres og det blir varmere vær? Trærnes tetratermkrav gir oss svaret.

• Hygen, Hans Olav; Nilsen, Irene Brox & Dalen, Elin (2022). Climate factsheets for world heritage sites in Norway. Full text in Research Archive Show summary

  UNESCO has defined 1154 properties of world heritage, which all face an increased threat of degradation of their values due to climate change. Eight world heritage sitesare based in Norway (with one transboundary). As a response to this known threat, The Directorate for Cultural Heritage in Norway has started to assess the threat, and effect, of climate change on the sites and the communities around the sites by applying a method called CVI (https://cvi-heritage.org/) to the world heritage site on Vega archipelago. As part of this process, an assessment of the known climate changes affecting Vega was developed.

• Dyrrdal, Anita Verpe; Nilsen, Irene Brox; Mayer, Stephanie; Hygen, Hans Olav; Dobler, Andreas & Hanssen-Bauer, Inger (2022). Decisions made when updating national climate projections for Norway. Full text in Research Archive Show summary

  The Norwegian Centre for Climate Services (NCCS), a national collaboration on the natural scientific knowledge for climate adaptation, has published the national climate assessment reports for Norway (Hanssen-Bauer et al., 2009; Hanssen-Bauer et al., 2015, Hanssen-Bauer et al., 2019). The work on national climate projections and associated products are described in Nilsen et al., 2022. In the wake of IPCC AR6 (CMIP6), the Norwegian Environment Agency has commissioned an update of the report “Climate in Norway 2100”, including new fine-scale climate projections for Norway. The report will present changes in past climate of the last 2000 years, current climate and hydrological normals and projected future changes in climate, hydrology and effects on natural hazards.

• Tajet, Helga Therese Tilley; Sagen, Stine; Agersten, Solfrid; Hygen, Hans Olav; Skaland, Reidun Gangstø & Lussana, Cristian [Show all 8 contributors for this article] (2022). Climatological Heat Waves in Norway - a base for Operational Warning System. Full text in Research Archive Show summary

  With increasing temperatures in Norway, the possibility of heat waves are assumed to increase. The Norwegian Meteorological Institute (MET Norway) is testing ways to monitor heat waves and possibly implement an operational warning system for heat waves in the future. For this work, it was necessary to assess the development of observed heat waves in Norway.

• Nilsen, Irene Brox; Eisner, Stephanie & Heiberg, Hanne (2022). Databehov i landbruket : oppsummering av interessegruppemøter om klimainformasjon i landbruk. Full text in Research Archive Show summary

  Denne rapporten oppsummerer to interessegruppemøter arrangert for landbruket. Noen brukerbehov kan innfris innenfor prosjektene, men det er sprik mellom hva forskningsprosjekter kan levere og hva interessegruppen har behov for, slik at ikke alle ønsker kan innfris. Enkelte ønsker har blitt videreformidlet til værvarslingstjenesten. Som et svar på brukerbehov etter interessegruppemøtet i 2022 beregnet vi tetraterm (varmekrav for ulike treslag i sommermånedene), inkludert endringer i tetraterm over tid. Tetratermen har økt i hele landet, og med det øker den potensielle utbredelsen av varmekjære trær. I den nettbaserte versjonen av rapporten beskrives også eksisterende dataportaler mer inngående, noe interessegruppen har etterspurt.

• Nilsen, Irene Brox; Kleivane, Ingeborg & Engeland, Kolbjørn (2022). Jernbanen må klargjøres for å takle framtidas flommer. Full text in Research Archive Show summary

  Etter flommene i 2011, 2013, og igjen i 2018, registrerte Bane NOR tre hundre skadepunkter langs Dovrebanen, med en beregnet kostnad på 300 millioner kroner. Det er et stort behov for bedre flomberegninger.

• Nilsen, Irene Brox; Heiberg, Hanne & Eisner, Stephanie (2022). Databehov i landbruket – rapport fra interessegruppemøter i prosjektene Emerald, Imprint og KSS. Full text in Research Archive Show summary

  Langtidsplanlegging av landbruket i et klimaendringsperspektiv krever relevant klimainformasjon. Denne teksten er skrevet som en oppsummering av interessegruppemøter mellom interessenter i landbruket og forskere i tre prosjekter i november 2019 og februar 2022. De tre prosjektene er EMERALD , IMPRINT og Norsk klimaservicesenter. Formålet med møtene har vært å konkretisere brukeres behov for klimainformasjon innen landbruk. Møtet i prosjektet EMERALD i november 2019 inviterte skogbruk, jordbruk og reindrift, men reindrift var ikke med i møtet i 2022, da fokuset hadde skiftet fra EMERALDs generelle oversikt over prosesser i kalde klima, til IMPRINTs hovedfokus på skogbruk.

• Narayanappa, Devaraju; Nilsen, Irene Brox & Falk, Stefanie (2021). Avskoging og den indiske monsunen ("Deforestation and the indian monsoon"). blogg.forskning.no- søkelys på skogplantning. Full text in Research Archive
• Nilsen, Irene Brox; Dalen, Thea Grobstok & Bryn, Anders (2021). Vil du være med og registrere tregrensa i sommer? Full text in Research Archive
• Bryn, Anders; Dalen, Thea Grobstok; Finne, Eirik Aasmo; Heiberg, Hanne; Nilsen, Irene Brox & Parmentier, Frans-Jan W. [Show all 22 contributors for this article] (2020). Natur i endring - en vandreutstilling. Full text in Research Archive
• Dyrrdal, Anita Verpe; Isaksen, Ketil; Jacobsen, Jens Kristian Steen & Nilsen, Irene Brox (2020). Present and future changes in winter climate indices relevant for access disruptions in Troms, northern Norway. Natural Hazards and Earth System Sciences. ISSN 1561-8633. 20(6), p. 1847–1865. doi: 10.5194/nhess-20-1847-2020. Full text in Research Archive Show summary

  A number of seaside communities in Troms, northern Norway, are vulnerable to sudden weather-induced access disruptions due to high-impact weather and dependency on one or few roads. In this paper we study changes in winter weather known to potentially cause access disruptions in Troms, for the present climate (1958–2017) and two future periods (2041–2070; 2071–2100). We focus on climate indices associated with snow avalanches and weather that may lead to for example slippery road conditions. In two focus areas, the most important results show larger snow amounts now compared to 50 years ago, and heavy snowfall has become more intense and frequent. This trend is expected to turn in the future, particularly at low elevations where snow cover during winter might become a rarity by 2100. Strong snow drift, due to a combination of snowfall and wind speed, has slightly increased in the two focus areas, but a strong decrease is expected in the future due to less snow. Events of heavy rain during winter are rather infrequent in the present winter climate of Troms, but we show that these events are likely to occur much more often in all regions in the future.

• Nilsen, Irene Brox; Tallaksen, Lena M. & Stordal, Frode (2017). Potential feedbacks between snow cover, soil moisture and surface energy fluxes in Southern Norway. Full text in Research Archive Show summary

  At high latitudes, the snow season has become shorter during the past decades because snowmelt is highly sensitive to a warmer climate. Snowmelt influences the energy balance by changing the albedo and the partitioning between latent and sensible heat fluxes. It further influences the water balance by changing the runoff and soil moisture. In a previous study, we identified southern Norway as a region where significant temperature changes in summer could potentially be explained by land-atmosphere interactions. In this study we hypothesise that changes in snow cover would influence the summer surface fluxes in the succeeding weeks or months. The exceptionally warm summer of 2014 was chosen as a test bed. In Norway, evapotranspiration is not soil moisture limited, but energy limited, under normal conditions. During warm summers, however, such as in 2014, evapotranspiration can be restricted by the available soil moisture. Using the Weather Research and Forecasting (WRF) model we replace the initial ground conditions for 2014 with conditions representative of a snow-poor spring and a snow-rich spring. WRF was coupled to Noah-MP at 3 km horizontal resolution in the inner domain, and the simulations covered mid-May through September 2014. Boundary conditions used to force WRF were taken from the Era-Interim reanalysis. Snow, runoff, soil moisture and soil temperature observational data were provided by the Norwegian Water Resources and Energy Directorate for validation. The validation shows generally good agreement with observations. Preliminary results show that the reduced snowpack, hereafter “sim1” increased the air temperature by up to 5 K and the surface temperature by up to 10 K in areas affected by snow changes. The increased snowpack, hereafter “sim2”, decreased the air and surface temperature by the same amount. These are weekly mean values for the first eight simulation weeks from mid May. Because of the higher net energy available (∼ 100 Wm-2) in sim 1, both the evapotranspiration and sensible heat fluxes increased. In sim 2, they decreased because of lower net energy. The ground heat flux decreased in sim1 (and increased in sim2). Large increases were seen in runoff, both surface and underground runoff, during the first weeks of sim2 (from mid May), but the timing of snowmelt was only slightly affected. This study contributes to a greater understanding of land-atmosphere interactions in a wet, temperate climate, in particular the role of snow cover (and snowmelt) and its feedback to the atmosphere.

• Nilsen, Irene Brox; Stagge, James Howard & Tallaksen, Lena M. (2016). A probabilistic approach to attribute warming to changes in atmospheric circulation. Full text in Research Archive Show summary

  Europe has been warming over the past decades, especially in southern Europe in summer and northern Europe in winter. To understand the causes of regional warming, it is common to separate the temperature change signal into changes in atmospheric circulation (or dynamic causes) and other factors, so-called within-type changes (or thermodynamic causes). For example, increasing temperatures due to greenhouse gases may alter the position and strength of the polar jet stream, thus causing a change in the atmospheric circulation signal. On the other hand, warming may be entirely independent of circulation, occurring as a general increase in surface temperature. With the aim to detect regions and time of the year in Europe in which recent warming can either be explained by changes in atmospheric circulation or by within-type changes, we suggest a novel probabilistic approach to calculate the circulation-induced trend, the part of the temperature trend that is induced by changes in atmospheric circulation. Through the use of resampling, in combination with a Monte Carlo test, we assessed the likelihood that the observed temperature trend can be explained entirely by changes in atmospheric circulation frequency. The temperature data originate from the gridded 0.5◦ Watch Forcing Data Era-Interim (WFDEI), and cover the period 1981–2010. The SynopVis Grosswetterlagen catalogue of circulation types was used to detect circulation-induced trends in the same time period. We analysed trends on the monthly time scale to reveal short-term responses, such as those related to snow or greening. The most wide-spread observed warming was found in summer, with up to 60% of the European land area experiencing a significant warming trend during August, most notable in eastern and northern Europe. In spring and autumn, the percent area with significant temperature increases reduced to 10–30%. In December and January, only 5% of the land area experienced significant warming, most pronounced in northern Scandinavia. The probabilistic approach revealed that changes in atmospheric circulation could not account for all the observed warming. Regions where the observed trend likely can be explained entirely by changes in atmospheric circulation include western Europe in May, eastern Europe in August and Scandinavia in September. In most of the regions and months experiencing significant trends, however, warming must be caused by other factors as well; such within-type changes potentially driven by feedbacks between the land surface and atmosphere. For two cases where the magnitude of the temperature trend was strongest, northern Scandinavia in December and in the Black Sea region in November, circulation types warmed over time. This confirms the role of within-type change, i.e., that circulation types changed their properties over time. This study provides an important contribution toward improved understanding of the causes of synoptic-scale temperature change in Europe, more specifically, the relative role of circulation-induced changes and within-type changes.

• Nilsen, Irene Brox; Tallaksen, Lena M. & Stagge, James Howard (2015). A probabilistic method of calculating circulation-induced trends. Full text in Research Archive Show summary

  The water cycle in Europe has changed substantially over the past three decades. Increasing runoff is observed during winter and at northern latitudes in particular. Spring and summer months, as well as southern latitudes, are facing drier conditions. To understand what is driving large-scale changes in runoff, we look into changes in precipitation and temperature and link these to changes in atmospheric circulation. Previous studies have used the method of trend ratios (Cahynová and Huth, 2009) to attribute precipitation and temperature trends to changes in the frequency of circulation types. A trend ratio is the ratio of hypothetical trend, i.e., the trend that would result due to changes in circulation type frequency only, to the observed trend. However, the method of trend ratios has two drawbacks. First, if the observed trend is small, division by a very low value results in a meaningless trend ratio and thus requires a cut-off value to keep the trend ratio within meaningful boundaries. Second, the method does not allow a comparison of the observed trend to the spread of possible outcomes, because the method of hypothetical trends is based on a deterministic model. We propose a new, more robust method for detecting the importance of circulation-induced changes in explaining the observed trends, which has the benefit of being a non-parametric statistical test that assesses the entire range of hypothetical trends. Instead of creating a hypothetical series by replacing the observation on a given day with the long-term climatic mean of a certain month and circulation type (as in the existing trend ratio method), the new approach replaces the observation on a given day with a random sample from the distribution of the variable for the given month and circulation type. The method introduces the possibility to assign a rejection rate, thus allowing statistical significance to be assessed. We apply the method on time series of precipitation and temperature from the gridded 0.5 degree WFDEI dataset, covering Europe (40-65N, 10W-30E). The SynopVis Grosswetterlagen catalogue of circulation types for the time period 1981-2010, the same period as the climatic data, is used. The new approach is used to map in which regions and months changes in atmospheric circulation is the dominating factor controlling changes in precipitation and temperature in Europe.

• Nilsen, Irene Brox; Tallaksen, Lena M.; Hisdal, Hege & Fleig, Anne Kristina (2014). Regional precipitation and temperature trend patterns in Europe (presentasjon av Paper I: Recent trends in monthly temperature and precipitation patterns in Europe). Full text in Research Archive
• Nilsen, Irene Brox & Tallaksen, Lena M. (2014). Temperature changes in Norway: Recent increases in WFDEI validated against interpolated observations. Full text in Research Archive Show summary

  Increased global temperatures have been observed during the past decades, and trends are expected to be greatest at high latitudes because of the polar amplification. Polar amplification may be caused by feedbacks between the atmosphere and the surface, such as the ice–albedo feedback: when increased temperatures cause increased snow melting, areas with a lower albedo are exposed and more radiation is absorbed. Thus, the temperature increase is enhanced. In a previous study, we analysed precipitation and temperature trends for the period 1979–2009 using gridded, bias-corrected re-analysis data from the WATCH Forcing Data Era-Interim (WFDEI). The data used consisted of daily temperature and precipitation data from 1 January 1979 to 31 December 2009 (31 years) and covered 34◦ –72◦ N and 13◦ W–32◦ E with a spatial resolution of 0.5◦ × 0.5◦ . Temperature and precipitation trends covering all of Europe were mapped using the Theil-Sen slope as a robust trend estimator. We found the greatest warming in Europe in the northernmost parts of Norway during December and January. The temperature trends for certain months and regions were as high as 8 ◦ C. In this study, monthly temperature trends from WFDEI will be compared with and validated against a daily interpolated dataset for Norway (presented at www.seNorge.no). This dataset has a spatial resolution of 1 × 1 km and covers mainland Norway. Residual kriging is applied to the data to ensure stationarity and remove bias. The daily data will be aggregated to the monthly time scale and monthly temperature trends will be calculated using the Theil-Sen slope for the period 1979–2009. The results will be compared visually with the WFDEI trends covering Norway. In addition, the distribution of trends as well as the fraction of positive and negative trends in the two datasets will be compared.

• Tallaksen, Lena M. & Nilsen, Irene Brox (2014). Norge er i gjennomsnitt blitt mer enn to grader varmere fra 1979 til 2009. Aftenposten Viten. ISSN 2464-3033. Full text in Research Archive Show summary

  Den største oppvarmingen finner vi om vinteren, med hele fem grader i januar. Har vi kunnskapen og beredskapen til å møte konsekvensene?

• Nilsen, Irene Brox (2014). Landoverflatemodellering og varmeflukser under hydrologiske ekstremer. Full text in Research Archive
• Nilsen, Irene Brox (2014). Does NOAH-LSM perform well for extremes, regarding heat fluxes? Full text in Research Archive Show summary

  As the climate and land surface in certain regions of Europe is drying or becoming wetter, certain feedback mechanisms may contribute to enhancing or reducing the effects on climate. For instance, soil moisture–precipitation feedbacks may act as a driving force to dry southern parts of Europe and to moisten northern parts. Understanding the partitioning of net radiation into turbulent fluxes into sensible and latent heat is important to represent these processes. In this project, NOAH will be run using ERA-Interim forcing data for four years covering both extremely wet and dry periods for regions in southern as well as northern Europe. In the first part, maps of the Bowen ratio will be plotted to establish the distribution of turbulent fluxes for wet and dry conditions. Second, the results will be compared with precipitation and temperature trends found in my PhD study to identify if possible concurrent changes in heat fluxes can explain the trends. The project contributes to understanding the driving forces controlling water availability which is important for water shortage mitigation.

• Nilsen, Irene Brox (2014). Hva gjør en klimaforsker? Full text in Research Archive
• Dyrrdal, Anita Verpe; Bakke, Sigrid Jørgensen; Hanssen-Bauer, Inger; Mayer, Stephanie; Nilsen, Irene Brox & Nilsen, Jan Even Øie [Show all 71 contributors for this article] (2025). Klima i Norge – kunnskapsgrunnlag for klimatilpasning oppdatert i 2025. Meteorologisk institutt. Full text in Research Archive Show summary

  I kjølvannet av FNs klimapanels sjette hovedrapport, og nedskalerte europeiske klimaframskrivninger, har Norsk klimaservicesenter fått i oppdrag å oppdatere rapporten Klima i Norge – Kunnskapsgrunnlag for klimatilpasning oppdatert i 2025. Dette er den tredje utgaven av ”Klima i Norge”-rapporten. Klima i Norge beskriver hvordan klimaendringer påvirker Norge, basert på målinger og klimaframskrivninger. Rapporten omhandler primært nasjonale forhold og definerer klimaendringer som endringer i atmosfære, kryosfære, hydrologi, skred og hav. Denne kunnskapen danner grunnlaget for klimatilpasning i Norge

• Bilt, Willem van der; Bakke, Jostein; Smedsrud, Lars H.; Sund, Monica; Schuler, Thomas & Westermann, Sebastian [Show all 47 contributors for this article] (2019). Climate in Svalbard 2100. Norsk klimaservicesenter. Full text in Research Archive Show summary

  This report was commissioned by the Norwegian Environment Agency in order to provide basic information for use in climate change adaptation in Svalbard. It includes descriptions of historical, as well as projections for the future climate development in the atmosphere, hydrosphere, cryosphere and ocean, and it includes effects on the physical nature e.g. on permafrost and various types of landslides and avalanches. The projections for the future climate are based on results in the IPCCs fifth assessment report. The report is to a large degree an assessment of existing literature and model results. New results from atmosphere, ocean and hydrological models are, however, also presented.

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