Impact of climate change on agriculture 

Agriculture is an important sector of any economy of the world. Agriculture productions are highly dependent on the climate change and variability. Changes in hydro-meteorological variables can influence crop yield and productivity at many places. Further, climate change can influence nutrient levels, soil moisture, water availability and other terrestrial parameters related to the agricultural productivity. Changes in the frequency and severity of droughts and floods could pose challenges for farmers and ranchers and threaten food safety. Further, changes in climate can influence meteorological conditions and thus can influence the crop growth pattern. It may also influence irrigation scheduling and water demand of the crops. The effects of climate change also need to be considered along with other evolving factors that affect agricultural production, such as changes in farming practices and technology.

The purpose of the proposed session is to gather scientific researchers related to this topic aiming to highlight ongoing researches and new applications in the field of climate change and agriculture. In this framework, original works concerned with the development or exploitation of advanced techniques for understanding the impact of climate change on agriculture will be invited.

The conveners of this session will encourage both applied and theoretical research in this area.

Co-organized by NH8
Convener: Prashant Kumar Srivastava | Co-conveners: Manika GuptaECSECS, R K Mall, George P. Petropoulos, George Stavroulakis
vPICO presentations
| Mon, 26 Apr, 13:30–15:00 (CEST)

vPICO presentations: Mon, 26 Apr

Chairpersons: Prashant Kumar Srivastava, George P. Petropoulos, Manika Gupta
M. Tufan Turp, Nazan An, Gökhan Özertan, and M. Levent Kurnaz

Apricot (Prunus armeniaca L.) is one of the most important export crops in Turkey and Turkey is the leader for both fresh and dried apricots production in the world. Apricot can be grown in all regions of Turkey with climate and vegetation diversities, except in the Eastern Black Sea Region and in the high plateaus of the East Anatolian Region. Malatya is the main producer province, which has good ecological and soil conditions in terms of apricot cultivation with the highest quality in Turkey. However, it is possible to talk about irregularities and decreases in apricot yield due to climate change in the region. Therefore, this study aims to observe climate change impacts on apricot yield in the main producer city, Malatya. Hereunder, climate projections were made at a 10 km horizontal resolution for the future period of 2021-2050 under the “worst-case” scenario (RCP8.5) using a regional climate model (RegCM4.4) for Malatya province considering 13 sub-regions. A statistical model, panel data method-multiple regression model, is designed to observe the effect of climate change and variability on the yield. Results indicate that adverse impacts of climate change on biological development of apricot lead to production irregularities and significant losses in yield in Malatya.


Acknowledgement: This research has been supported by Boğaziçi University Research Fund Grant Number 16763.

How to cite: Turp, M. T., An, N., Özertan, G., and Kurnaz, M. L.: Impact of Climate Change on Apricot Yield in Turkey in the Near Future, EGU General Assembly 2021, online, 19–30 Apr 2021, EGU21-5261,, 2021.

Nazan An, M. Tufan Turp, and M. Levent Kurnaz

Climate is a crucial factor for agricultural production and productivity. Foreseeing climate change in the future means predicting the possible effects on agriculture, and such studies observing year-dependent variability and predicting the effects of the near and mid-future climate change are valuable for both food security and economic value especially for countries which have commercial agricultural products like Turkey, as a Mediterranean Basin country with significant agricultural diversification. Apricot (Prunus armeniaca L.), which is one of Turkey's most important export products are expected to be affected significantly by climate change. Therefore, it is very important to see whether it will grow in the same regions in the future due to climatic changes for apricot. Hereunder, high resolution climate data, as an input for the membership function to be applied for classification of the climate suitability index, were obtained from RegCM4.4 under the RCP8.5 scenario for the period of 2021-2050 v.s. 1991-2018 for different phenological periods. Briefly, results indicate that adverse changes in climate suitability conditions for current apricot growing locations, 48 locations in the study, and the number of climate suitable locations for apricot will significantly decreases in the near and mid-future.  



Acknowledgement: This research has been supported by Bogazici University Research Fund Grant Number 17601.

How to cite: An, N., Turp, M. T., and Kurnaz, M. L.: Assessment of Climate Suitability for Prunus armeniaca L. in Turkey in a Changing Climate, EGU General Assembly 2021, online, 19–30 Apr 2021, EGU21-5382,, 2021.

Mosisa Wakjira, Darcy Molnar, Nadav Peleg, Johan Six, and Peter Molnar

Rainfall timing is a key parameter that farmers rely on to match the cropping season with the time window over which seasonal precipitation provides adequate soil moisture to meet plant growth demand. The unpredictability of rainfall timing affects the selection of an optimal growing season, and hence crop production in regions where rainfed agriculture (RFA) is practiced. In this study, we (a) map rainfall timing, and its interannual variability and changes over RFA areas across Ethiopia for the period 1981-2010, and (b) explore the impact of variability in rainfall timing on cereal crop production in the period 1995-2010.

For the mapping of rainfall timing, we used the quasi-global CHIRPS precipitation dataset over Ethiopia. We use information entropy on monthly rainfall to define the rainfall seasonality metrics, i.e. the relative entropy and dimensionless seasonality index, and map them in space. For rainfall timing attributes, we determine the onset, cessation, and length of the wet season from LOESS-smoothed cumulative pentad rainfall anomalies for each hydrological year. Changes in seasonality metrics and rainfall timing attributes are analyzed using non-parametric methods. We show that high seasonality (unimodal rainfall regime) is located in the northern part of the Ethiopian RFA area where high annual rainfall and high relative entropy are coincident, and where the onset of the rainfall season varies between mid-April to late-June and cessation occurs between mid-September to late-October. Low seasonality in the southern part of the Ethiopian RFA area shows low relative entropy regardless of the annual rainfall total. We observed a considerable interannual variability both in seasonality and rainfall timing over the study period, especially in the onset and length of the wet season. The length of the wet season and magnitude of seasonal rainfall are predominantly controlled by the timing of rainfall onset.

For the impacts of rainfall timing on crop production, we used cereal crop production data from the Central Statistical Agency of Ethiopia for the period 1995-2010 in 45 administrative zones. We carried out a parametric correlation analysis between rainfall timing and rescaled and de-trended crop production anomalies. We observe that anomalies in seasonal cereal crop production in RFA areas are significantly correlated with anomalies in rainfall onset (negatively) and the length of the wet season (positively), with a regional average production loss of 3% per pentad of late rainfall onset, and 2.7% per pentad of shorter length of the wet season. Seasonal rainfall is less strongly correlated with cereal crop production anomalies compared to the rainfall onset. These results show that the interannual variability in rainfall timing (start of the rainy season) even under present climate has strong impacts on crop yields in RFA areas in Ethiopia, and this may be exacerbated in a future climate.

How to cite: Wakjira, M., Molnar, D., Peleg, N., Six, J., and Molnar, P.: Regularity of rainfall timing across Ethiopia: implications for crop production, EGU General Assembly 2021, online, 19–30 Apr 2021, EGU21-9279,, 2021.

Sabine Egerer, Andrea Fajardo, Michael Peichl, Oldrich Rakovec, Luis Samaniego, and Uwe Schneider

The agricultural sector is particularly vulnerable to changing weather and climate conditions. Climate projections for Germany until the end of this century demonstrate higher temperatures and a substantial net water deficit during the summer months when agriculture is in high demand for water. Additionally, the frequency and length of dry periods increase as a consequence of climate change. Irrigation was introduced in the 1960s in Northeast Lower Saxony (Germany) to become more resilient to changing weather and climate conditions and prevent yield losses. The region involves today the largest irrigated area in Germany. However, during the drought in 2018 water extractions for irrigation by far exceeded the institutional limit. Water using conflicts are likely to strengthen in the future as the irrigation demand will increase. In this study, we explore the importance of irrigation as a climate change adaptation measure in the region. First, we employ a statistical regression model to investigate whether regional climate, hydrological, and irrigation data on a monthly and county level scale are adequate to describe potato yield changes between 1978 and 2018. Soil moisture information originates from the mesoscale hydrologic model (mHM). Irrigation is estimated based on the climatic water balance and crop water demand. These estimations are scaled with irrigation data from local authorities to account for realistic monthly water withdrawals. Second, we use the process-based crop model EPIC to estimate potato crop yields and to validate the performance of the statistical approach. We analyze future yield changes based on climate model projections for the 21st century using the two approaches. We investigate different irrigation scenarios as a potential climate change adaptation measure. By comparing the statistical and process-based approaches we explore whether a rather simplistic statistical approach captures the main processes of the climate change impact on yields.

How to cite: Egerer, S., Fajardo, A., Peichl, M., Rakovec, O., Samaniego, L., and Schneider, U.: The role of irrigation on potato yields in Northern Germany under climate change, EGU General Assembly 2021, online, 19–30 Apr 2021, EGU21-9554,, 2021.

Andrea Fajardo, Sabine Egerer, Luca Doro, Livia Rasche, and Uwe Schneider

Historically, there has not been major disputes over water rights between agriculture and domestic use in Northeastern Lower Saxony (NELS). In the 30-year mean from 1971 to 2000, the water balance national average was positive at 185 mm. According to the climate report for Lower Saxony, the water surplus will decrease by two-thirds for period 2070-2100 for RCP 8.5 scenario. NELS might be particularly vulnerable to more unstable precipitation patterns due to the sandy soil textures.

Frequency and intensity in drought events will intensify in the coming decades; irrigation investments might be the most promising option to attain stable yields for existing crops. Nevertheless, assessing feasible irrigation strategies requires consistent information on several crop processes and their impact by different weather conditions and irrigation strategies. EPIC crop model can generate data that allow testing of various irrigation options and their future implications. This offers an opportunity to save time resources, facilitating this way the decision-making processes.

In this study, we have simulated with EPIC crop model different irrigation levels changing application dates in regards to seasonal water deficit. The simulations use the crop rotation (potato – sugar beet – silage corn – soybean – winter wheat) under three RCPs scenarios (2.6, 4.5 and 8.5). With this research, we aim to advance the understanding of how irrigation influences soil quality and its contribution to the agriculture practices in Lower Saxony to emissions. Moreover, we investigated the effect of planting and harvesting dates on yield and soil quality.

How to cite: Fajardo, A., Egerer, S., Doro, L., Rasche, L., and Schneider, U.: Effects on irrigation patterns and management dates on silage corn and winter wheat yields in Northern Germany under climate change, EGU General Assembly 2021, online, 19–30 Apr 2021, EGU21-9687,, 2021.

Marie-Louise Schärer, Andreas Lüscher, Lucia Fuchslueger, Andreas Richter, and Ansgar Kahmen

Introduction Reoccurring drought events can severely restrict forage production. However, experimentally drought stressed temperate forage grasslands have recently been reported to recover quickly after drought stress and re-wetting (DRW) and to be even more productive after drought than non-drought stressed control plots (Hofer et al., 2017; Hahn et al., in press). Although several studies show increased nutrient availability and microbial activity after DRW in grasslands (Bünemann et al., 2013; Sundert et al., 2020), an in-depth understanding if or how these mechanisms determine forage yield recovery is still missing.

Methods This study examined the effect of a 2-month experimental summer drought under different nitrogen (N) fertilizer applications on the recovery of high-input Lolium perenne swards after re-wetting. Yield performance, physiology, nutrient availability and soil microbial activity were assessed over 2 years during and after the drought treatment. In addition, a post-drought transplantation experiment of control and DRW soil and plants withdrawn from the field was conducted to disentangle plant physiological and soil nutrient cycling effects on yield recovery after drought.

Results Under all N applications, DRW outperformed the control yield in the field and showed higher N mineralization rates and higher soil N and K availabilities. Transplanted DRW plants showed longer but thinner leaves and decreased yields compared to control plants, irrespective of the soil’s DRW treatment. In contrast, DRW soils induced strongly increased L. perenne yields (on average +25%) compared to control soils. In summary, our data show that despite impaired plant growth after DRW, formerly drought stressed swards surpass control yields by profiting of higher mineralization rates and higher nutrient availability.


Bünemann EK, Keller B, Hoop D, Jud K, Boivin P, Frossard E (2013) Increased availability of phosphorus after drying and rewetting of a grassland soil: processes and plant use. Plant and Soil 370: 511–526

Hahn C, Lüscher A, Ernst-HaslerS, Suter M, Kahmen A (in press) Timing of drought in the growing season and strong legacy effects determine the annual productivity of temperate grasses in a changing climate. Biogeosciences.

Hofer D, Suter M, Buchmann N, Lüscher A (2017) Nitrogen status of functionally different forage species explains resistance to severe drought and post-drought overcompensation. Agriculture, Ecosystems & Environment 236: 312–322

Sundert KV, Brune V, Bahn M, Deutschmann M, Hasibeder R, Nijs I, Vicca S (2020) Post-drought rewetting triggers substantial K release and shifts in leaf stoichiometry in managed and abandoned mountain grasslands. Plant Soil 448: 353–368

How to cite: Schärer, M.-L., Lüscher, A., Fuchslueger, L., Richter, A., and Kahmen, A.: The underlying mechanisms of post-drought yield outperformance in L. perenne, EGU General Assembly 2021, online, 19–30 Apr 2021, EGU21-10850,, 2021.

Florian Ellsäßer, Elena Xoplaki, Lorine Behr, Juerg Luterbacher, Andrea Toreti, and Matteo Zampieri

In the last decades, Europe has experienced an increase in the occurrence of extreme spring-to-summer heat and rainfall deficit. The compound impact of both hazardous weather events causes extreme drought conditions, which are likely to increase in frequency in the coming decades, with large impacts on agriculture and crop productivity. In this study, we analyze and attribute the effects of compound weather extremes on yield anomalies in Germany from 1989 to 2019.

To characterize the impact of compound events on irrigated and rainfed crops, statistical index-based approaches have widely been used, linking historic weather aggregates to yield records. To analyze and predict the impact of compound extreme events on crop yield, productivity and cultivation area at subnational level for Germany, we merged available yield data from multiple sources to create a consistent yield record of the last 30 years at county level. We then calculated indices on gridded meteorological data and records of phenological crop phases and agricultural practices, covering three decades, to analyze the effect of compound weather extremes on winter wheat yield.

We evaluated the SPEI (Standardized Precipitation Evaporation Index) for the 6-month period before winter wheat is harvested, to account for extremes in excess and lack of water availability. We further calculated the HMD (Heat Magnitude Day) index for the 3-month period before harvest, to assess the impact of heat stress conditions. Finally, a composite indicator the CSI (Combined Stress Index), based on a linear superposition of the standardized HMD and SPEI, is applied. The CSI is calibrated to local conditions by determination of coefficients that maximize the explanatory power of the index, using a bilinear ridge regression and county level yield observations.

The results of this study help to better understand the impacts of compound extremes on winter wheat in Germany and reveal regions that are especially threatened by yield losses from compound weather extremes.

How to cite: Ellsäßer, F., Xoplaki, E., Behr, L., Luterbacher, J., Toreti, A., and Zampieri, M.: Impact of compound weather extremes on winter wheat in Germany, EGU General Assembly 2021, online, 19–30 Apr 2021, EGU21-11565,, 2021.

Raed Hamed, Anne Van Loon, Jeroen Aerts, and Dim Coumou

The US agriculture system supplies more than one third of globally traded soybean, of which 90% is produced under rainfed agriculture. This makes the commodity particularly sensitive to weather and climate variability. Previous research has shown that annually averaged climate conditions explain about a third of global crop yield variability. Additionally, although less studied so far, crops are sensitive to specific short-term weather conditions, isolated or co-occurring at key moments throughout the growing season. Here we aim to identify key within-season weather and climate variables that can explain soybean yield variability in the US while exploring synergies between drivers that can have compounding impacts. The study combines weather data from reanalysis and satellite-based evapotranspiration and root-zone soil moisture with sub-national crop yield estimates using statistical methods that account for interaction effects. We also analyze the historic changes in identified key driving conditions in order to explore the effects of current climatic trends on yields. Our preliminary results indicate positive yield response to higher minimum temperature early and late in the season whereas the largest effect on soybeans is driven by the harmful co-occurrence of high temperature and low moisture levels during the summer flowering period significantly reducing yields on average in the US  by one standard deviation. The magnitude of the response to climate drivers varies across the spatial domain highlighting the need to focus on local and season specific management strategies. On the bright side, recent trends in temperature have not increased the likelihood of low yields. This is because the overall warming conditions reduce the risk of frost early and late in the season. Conversely, a peculiar cooling trend during the summer period attributed to agricultural land use is beneficial for yields when crops are most sensitive to high temperatures. Our study provides a detailed understanding of the current relationship between climate and soybean yields in the US. This is particularly relevant for adaptation and mitigation strategies aimed at avoiding low yields in a context of increasing food demand and climate change.

How to cite: Hamed, R., Van Loon, A., Aerts, J., and Coumou, D.: The impacts of hot-dry compound extremes on US Soybean yields, EGU General Assembly 2021, online, 19–30 Apr 2021, EGU21-12965,, 2021.

Christina Lekka, George P. Petropoulos, Dimitrios Triantakonstantis, Spyros Detsikas, and Christos Chalkias


The National Map of Saline – Alkaline Soils of Greece was recently developed within the initiative of the European Soil Partnership (ESP) of FAO. The technique combines between other MODIS satellite imagery, spatial interpolation methods and ground surveying to derive at 1 km spatial resolution maps of soil’s salinity (SS) and soil organic carbon (SOC).

The present study investigates for the first time the development of higher resolution maps of these soil properties adopting the aforementioned methodology. Furthermore, this study attempted to estimate the Carbon sequestration (SOC) using Remote Sensing and geostatistic methods of spatial analysis, a concern that is eminent today due to its effect on climate change mitigation.

As a case study the island of Mytilene in Greece is used, for which detailed information on soil properties as well as climatic, geomorphological, geological and soil data was available from previous studies. An MCDA (Multiple Criteria Decision Analysis) method was applied in a GIS environment using Landsat satellite imagery for the composition of a Saline - Alkaline map. Between the key soil parameters estimated spatially included the Electrical Conductivity (EC), Exchangeable Sodium Percentage (ESP) and pH. Geospatial data analysis methods were implemented to visualize all the derived parameters related for the study area and to analyze the final products in the spatial domain.

Finding suggests that climate change and soil directly affect one another. The impact of environmental and climate change in addition to unsustainable agricultural practices seems to be linked to salinity increase, soil erosion and loss of organic matter.  In addition, when land degradation as well as erosion and loss of vegetation occur, SOC emissions increase. Under these conditions, soil cannot absorb enough amounts of CO2, especially when soil salinization and sodicity exists; inputs are further limited due to declines in vegetation health. The role of geoinformation technologies in support of sustainable agricultural production under the pressure of both climate change and anthropogenic activities is also discussed within the present study framework.  

KEYWORDS: geoinformation, soil, pH, salinity, soil organic carbon, geostatistics, earth observation, GIS, Greece

How to cite: Lekka, C., Petropoulos, G. P., Triantakonstantis, D., Detsikas, S., and Chalkias, C.: Geoinformation in support of sustainable soils’ management to strengthen resilience under the pressure of climate change, EGU General Assembly 2021, online, 19–30 Apr 2021, EGU21-12973,, 2021.

Dimitris Triantakonstantis and Spyros Detsikas

Soil organic carbon (SOC) is the carbon that remains in the soil after the partial decomposition of any material produced by living organisms. It is an essential parameter for agricultural production, the potential sequestration of CO₂ in soil and a vital soil function for global carbon cycle. However, a vast potential of soil carbon is removed from agricultural soils due to non-sustainable soil management practices. Mapping SOC and its changes over time and space is highly valuable for estimating the CO₂ emissions and effects of climate change to the environment. In the present work, the Greek National Map of SOC is presented calculating the SOC stock in 30 arc-seconds spatial resolution using the Global Soil Partnership and Food and Agriculture Organization of the United Nations (FAO) guidelines for SOC mapping. The presented methodology considers the reference framework of the SCORPAN model for digital soil mapping, which can predict SOC stocks in correspondence with soil forming factors. Among the key variables used for estimating SOC stocks are environmental covariates such as climate and meteorological data, thematic maps, digital terrain data, geomorphometry and soil data. Data mining and geostatistical techniques (random forests, support vector machines, regression-kriging) are used to estimate the SOC stocks. Internal and external map accuracy is used to evaluate the performance of the Greek National SOC map. Accuracy of FAO’s methodology was examined herein using different modelling approaches. As indicated in the results, the most accurate map was produced by the random forest technique and an accuracy of FAC2=0.968, RMSE=0.322 and r=0.756. The main findings are also discussed herein covering aspects relevant to the method implementation, validation and feasibility of operational implementation.

Keywords: soil organic carbon, climate change, soil management practices, Greek National Map

How to cite: Triantakonstantis, D. and Detsikas, S.: Greek National Map of Soil Organic Carbon, EGU General Assembly 2021, online, 19–30 Apr 2021, EGU21-13211,, 2021.

Sebastian Bathiany, Diana Rechid, Susanne Pfeifer, Juliane El Zohbi, Klaus Goergen, Niklas Wagner, Patrizia Ney, and Alexandre Belleflamme

Agriculture is among the sectors that are most vulnerable to extreme weather conditions and climate change. In Germany, the subsequent dry and hot summers 2018, 2019, and 2020 have brought this into the focus of public attention. Agricultural actors like farmers, advisors or companies are concerned with such interannual variability and extremes. Yet, it often remains unclear what long-term adaptation options are most suitable in the context of climate change, mainly because climate projections have uncertainties and are usually not tailored to meet requirements, measures and scales of the individual practicioners. In the ADAPTER project, we explore regional and local change on the weather- and climate-related time scales and together with stakeholders (administration, plant breeders, educators, agricultural advisors), we co-design tailored climate change indices and usable products.

In this contribution, we provide a snapshot view of our stakeholders' requirements regarding information about climate change over the next decades. We then focus on the analysis of three groups of indices based on 85 regional climate model simulations from Coordinated Downscaling Experiments over Europe - EURO-CORDEX: (i) changes in daily temperature variability, (ii) occurrence of agricultural droughts in summer, (iii) compound events of combined dryness and elevated temperatures during the same events. We show that these user-oriented, newly constructed indices can capture relevant changes during important phenological development states of typical crops. Finally, we discuss first implications of our findings for different adaptation strategies in Mid-Europe, such as alternating crop rotations, irrigation strategies or plant breeding. The analysis products presented are interactively and publicly available through a product platform ( for agricultural stakeholders.

How to cite: Bathiany, S., Rechid, D., Pfeifer, S., El Zohbi, J., Goergen, K., Wagner, N., Ney, P., and Belleflamme, A.: Simulation-based indices for a climate-resilient agriculture - insights from ADAPTER, EGU General Assembly 2021, online, 19–30 Apr 2021, EGU21-14408,, 2021.

Jop Koopman

This research proposal aims to contribute to the body of knowledge about smallholder farmers’ anthropogenic climate change perceptions, and how said perceptions shape adaptability and resilience, resulting in adopting new and old strategies grounded in local knowledge. 86% of farms in Indonesia are owned and cultivated by smallholders. This group is among the poorest and most vulnerable in Indonesia while contributing the most considerable part to the available food production in the entire country. Smallholder farmers from Lombok are, in particular, among the most vulnerable due to their socio-economic status and the high exposure of the region to climate-related hazards. The group’s perceptions and discourse of anthropogenic change are shaped by local knowledge and the social environment, and top-down initiatives from the government and NGOs. The interplay of both factors has yet to be researched. This research is ethnographic and qualitative and will be conducted during three field-site visits of 6 months each. In apprentice anthropology, the notion that the farmer is the expert on local knowledge and new strategies as a means to adapt will be included wherein the researcher is the student and the respondent the teacher. The choice for this type of methodology is made because the majority of research on the intersection of agriculture, climate change, and social science is quantitative and does not consider local farmers as experts in their own field. Therefore, participant observation, semi-structured interviews, document analysis, and group discussions will be used.

How to cite: Koopman, J.: Small farmers, large issues: discourse, local knowledge, and strategies, EGU General Assembly 2021, online, 19–30 Apr 2021, EGU21-14618,, 2021.

The agricultural pressure cooker: how climate, demography, and value chain megatrends affect European rural regions
Niels Debonne
Zoe Linder, Annelie Holzkämper, and Massimiliano Zappa

According to climate projections, rainfall rates and summer discharge from snow and glacier melt in Switzerland are expected to decrease by the end of the 21st century. This may lead to limited water availability for irrigation in agriculture in the future and high irrigation water demand especially during the summer months, which consequently enhances the problem of water scarcity for agriculture.

These predicted changes make the identification of timescales, frequencies, and geographical pattern of water scarcity a fundamental concern for future agricultural practices. Therefore, the main aim of this work is to investigate climate change impacts on water resources and the consequences on irrigation water supply in Switzerland. By creating maps of the geographic distribution of natural water resources available according to climate projections until the end of the 21st century using ArcGIS, the severity of water scarcity is quantified, while regional differences and the most affected areas can be revealed.

The expected outcomes are increasing days of water scarcity per year over the course of the 21st century, while those regions furthest away from melt water sources and lakes will be most affected. This in turn might lead to restricted irrigation potential, making more efficient water use indispensable in Switzerland, while creating general shifts to more water-resistant crops in Swiss agricultural practices.

How to cite: Linder, Z., Holzkämper, A., and Zappa, M.: Climate change impacts on irrigation water resource in Switzerland, EGU General Assembly 2021, online, 19–30 Apr 2021, EGU21-14990,, 2021.

Matteo Rolle, Stefania Tamea, and Pierluigi Claps

Intensification of studies of the agricultural water requirement is a main challenge in a globalized world, where food production is pushed to meet the needs of a growing population and the international trade network requires large-scale planning policies. Agriculture is the human activity that consumes most of the withdrawn freshwater and climate change can greatly influence the amount of irrigation required by crops. In recent years, the widespread availability of satellite images is providing an important contribution to water resources management, offering data at high spatio-temporal resolution over an interestingly long period of time.

This study deals with the temporal variability of global water requirement of the main crops, which is assessed through a comprehensive model, driven by climate forcings, that estimates the daily crop water requirement on a spatial resolution of 5 arc-min (or 0.0833°) from 1950 to 2020. The model computes a soil water balance using daily input data of precipitation and evapotranspiration, based on the high-resolution ERA5 reanalysis dataset from the Climate Change Service of the Copernicus Program, which combines satellite information and ground measurements. The distribution of harvested areas and the length of crop development phases are kept constant, to analyze the variability of crop water requirement strictly related to climate forcings, both in terms of precipitation (green water) and irrigation (blue water). The model considers the separation between irrigated and rainfed areas, in order to provide a consistent spatial distribution of irrigation requirements. Examining the spatio-temporal variability of the crop water requirement can support considerations on the effects of global warming in different areas in the world.

How to cite: Rolle, M., Tamea, S., and Claps, P.: Spatio-temporal variability of global crop water requirement, during 1950-2020, EGU General Assembly 2021, online, 19–30 Apr 2021, EGU21-15698,, 2021.