A comparative estimate of climate change impacts on cotton and maize in Greece

Abstract The impact of climate change on cotton and maize was estimated on the basis of three IPCC Emission Scenarios (A1B, A2, B2) for seven main agronomic areas during three periods, 1961–1990, 2021–2050 and 2071–2100. All climate models were assessed for their ability to identify the yield differences through the standardized discriminant function coefficients. Discriminant analysis was performed for each period. For cotton, using the A1B scenario, areas of Western Greece exhibited the most favourable results in terms of yield increase, compared to other regions, ranging up to the maximum value of +24%. This tendency became more pronounced towards the end of the century reaching an increase of +31%. In the A2 scenario, all the areas had a positive impact on their yield change rising up to 30% in areas of central Greece. A positive change for all regions was observed for scenario B2 ranging from +10% to +25%. In maize, the scenario A1B produced small changes in yields, not exceeding 5%. For A2 scenario, yield change varied from −5.7% to +3.6%. Scenario B2 gave more optimistic estimates of yield changes towards the end of the century, in some cases exceeding 5%.

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Formulating and testing a method for perturbing precipitation time series to reflect anticipated climatic changes

Hydrology and Earth System Sciences ◽

10.5194/hess-21-345-2017 ◽

2017 ◽

Vol 21 (1) ◽

pp. 345-355 ◽

Cited By ~ 7

Author(s):

Hjalte Jomo Danielsen Sørup ◽

Stylianos Georgiadis ◽

Ida Bülow Gregersen ◽

Karsten Arnbjerg-Nielsen

Keyword(s):

Climate Change ◽

Time Series ◽

Climate Models ◽

Climate Change Impacts ◽

Future Climate ◽

High Temporal Resolution ◽

Urban Water ◽

Precipitation Time Series ◽

Event Scale ◽

The Impact

Abstract. Urban water infrastructure has very long planning horizons, and planning is thus very dependent on reliable estimates of the impacts of climate change. Many urban water systems are designed using time series with a high temporal resolution. To assess the impact of climate change on these systems, similarly high-resolution precipitation time series for future climate are necessary. Climate models cannot at their current resolutions provide these time series at the relevant scales. Known methods for stochastic downscaling of climate change to urban hydrological scales have known shortcomings in constructing realistic climate-changed precipitation time series at the sub-hourly scale. In the present study we present a deterministic methodology to perturb historical precipitation time series at the minute scale to reflect non-linear expectations to climate change. The methodology shows good skill in meeting the expectations to climate change in extremes at the event scale when evaluated at different timescales from the minute to the daily scale. The methodology also shows good skill with respect to representing expected changes of seasonal precipitation. The methodology is very robust against the actual magnitude of the expected changes as well as the direction of the changes (increase or decrease), even for situations where the extremes are increasing for seasons that in general should have a decreasing trend in precipitation. The methodology can provide planners with valuable time series representing future climate that can be used as input to urban hydrological models and give better estimates of climate change impacts on these systems.

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Reviewing our options: How can we address climate change impacts in hydrogeological studies?

10.5194/egusphere-egu2020-16143 ◽

2020 ◽

Author(s):

Steffen Birk ◽

Raoul Collenteur

Keyword(s):

Climate Change ◽

Climate Models ◽

Regional Climate ◽

Climate Change Impacts ◽

Regional Climate Models ◽

Hydrogeology Journal ◽

Strong Increase ◽

Emission Scenarios ◽

Climate Change Research ◽

Model Chain

<p>Arguably, the groundwater community has responded more slowly to the challenges posed by climate change than other fields of (hydrological) science. However, in recent years a strong increase in studies addressing climate change impacts on groundwater is observed, and recommendations on the methodology of such studies have been developed and discussed (e.g. Holman et al., Hydrogeology Journal, 2012). Following the common practice in other fields of climate change research, it was suggested that assessments of climate change impacts on groundwater should be based on multiple emission scenarios and a range of global and regional climate models. This scenario-based, top-down approach involves the propagation of multi-model ensembles through a model chain starting from emission scenarios to global and regional climate models to impact models such as hydrological and groundwater models. However, as the uncertainty increases at each step of the model chain, the uncertainty in the assessment of local climate change impacts and the resulting recommendations for adaptation options likely are very high and thus of little use in practice. A vulnerability-based, bottom-up approach starting from the identification and analysis of the factors that are relevant for coping with climate change in a given system, therefore, was proposed as a complementary approach (e.g. Wilby and Dessai, Weather, 2010). &#8220;Storylines&#8221; (Shephard et al., Climatic Change, 2018) that aim at representing uncertainty in physical aspects of climate change in an event-based rather than probabilistic way appear to be consistent with the latter concept. In this poster we relate these concepts of climate change research to methodological frameworks established in hydrogeological research (e.g. multi-model approaches). We present an overview of potential tools, such as trading-space-for-time, historical data analysis, sensitivity analysis, climate projections and controlled experiments, that can be used to study climate change impacts, and we discuss their role and applicability within more general methodological frameworks.</p>

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Assessing the Impact of Projected Climate Change on Zoo Visitation in Toronto (Canada)

Journal of Geography and Geology ◽

10.5539/jgg.v8n2p30 ◽

2016 ◽

Vol 8 (2) ◽

pp. 30 ◽

Cited By ~ 4

Author(s):

Micah J. Hewer ◽

William A. Gough

Keyword(s):

Climate Change ◽

Climate Models ◽

Positive Impact ◽

Global Climate ◽

Global Climate Models ◽

Change Scenario ◽

Climate Change Scenarios ◽

Intergovernmental Panel ◽

Local Climate ◽

The Impact

Weather and climate have been widely recognised as having an important influence on tourism and recreational activities. However, the nature of these relationships varies depending on the type, timing and location of these activities. Climate change is expected to have considerable and diverse impacts on recreation and tourism. Nonetheless, the potential impact of climate change on zoo visitation has yet to be assessed in a scientific manner. This case study begins by establishing the baseline conditions and statistical relationship between weather and zoo visitation in Toronto, Canada. Regression analysis, relying on historical weather and visitation data, measured at the daily time scale, formed the basis for this analysis. Climate change projections relied on output produced by Global Climate Models (GCMs) for the Intergovernmental Panel on Climate Change’s 2013 Fifth Assessment Report, ranked and selected using the herein defined Selective Ensemble Approach. This seasonal GCM output was then used to inform daily, local, climate change scenarios, generated using Statistical Down-Scaling Model Version 5.2. A series of seasonal models were then used to assess the impact of projected climate change on zoo visitation. While accounting for the negative effects of precipitation and extreme heat, the models suggested that annual visitation to the zoo will likely increase over the course of the 21st century due to projected climate change: from +8% in the 2020s to +18% by the 2080s, for the least change scenario; and from +8% in the 2020s to +34% in the 2080s, for the greatest change scenario. The majority of the positive impact of projected climate change on zoo visitation in Toronto will likely occur in the shoulder season (spring and fall); with only moderate increases in the off season (winter) and potentially negative impacts associated with the peak season (summer), especially if warming exceeds 3.5 °C.

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Which climatic modeling to assess climate change impacts on vineyards?

OENO One ◽

10.20870/oeno-one.2016.0.0.1869 ◽

2017 ◽

Vol 51 (2) ◽

pp. 91 ◽

Cited By ~ 1

Author(s):

Hervé Quénol ◽

Iñaki Garcia de Cortazar Atauri ◽

Benjamin Bois ◽

Andrew Sturman ◽

Valérie Bonnardot ◽

...

Keyword(s):

Climate Change ◽

Climatic Change ◽

Climate Models ◽

Climate Change Impacts ◽

Future Climate ◽

Phenological Stages ◽

Different Types ◽

Assess Climate Change ◽

The Impact

The impact of climatic change on viticulture is significant: main phenological stages appear earlier, wine characteristics are changing,... This clearly illustrates the point that the adaptation of viticulture to climate change is crucial and should be based on simulations of future climate. Several types of models exist and are used to represent viticultural climates at various scales. In this paper, we propose a review of different types of climate models (methodology and uncertainties) and then few examples of its application at the scale of wine growing regions worldwide.

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Quantifying uncertainties of permafrost carbon-climate feedbacks

10.5194/bg-2016-544 ◽

2017 ◽

Author(s):

Eleanor J. Burke ◽

Altug Ekici ◽

Ye Huang ◽

Sarah E. Chadburn ◽

Chris Huntingford ◽

...

Keyword(s):

Climate Change ◽

Land Surface ◽

Climate Models ◽

Emission Scenario ◽

Emission Scenarios ◽

Climate Feedbacks ◽

Land Surface Models ◽

Surface Models ◽

Warming World ◽

The Impact

Abstract. The land surface models JULES (two versions) and ORCHIDEE-MICT, each with a revised representation of permafrost carbon, were coupled to the IMOGEN intermediate complexity climate and ocean carbon uptake model. IMOGEN calculates atmospheric carbon dioxide (CO2) and local monthly surface climate for a given emission scenario with the land-atmosphere CO2 flux exchange from either JULES or ORCHIDEE-MICT. These simulations include feedbacks associated with permafrost carbon changes in a warming world. Both IMOGEN-JULES and IMOGEN-ORCHIDEE-MICT were forced by historical and three alternative future CO2 emission scenarios. Simulations were performed for different climate sensitivities and regional climate change patterns based on 22 different Earth System Models (ESM) used for CMIP3 (phase 3 of the Coupled Model Intercomparison Project), allowing us to explore climate uncertainties in the context of permafrost carbon – climate feedbacks. Three future emission scenarios consistent with three representative concentration pathways: RCP2.6; RCP4.5 and RCP8.5 were used. Paired simulations with and without frozen carbon processes were required to quantify the impact of the permafrost carbon feedback on climate change. The additional warming from the permafrost carbon feedback is between 0.2 and 12 % of the change in the global mean temperature (ΔT) by year 2100 and 0.5 and 17 % of ΔT by 2300, this range reflecting differences in land surface models, climate models and emissions pathway. As a percentage of ΔT, the permafrost carbon feedback has a greater impact on the low emission scenario (RCP2.6) than on the higher emissions scenarios suggesting that permafrost carbon should be taken into account when evaluating heavy mitigation and stabilizations scenarios. Structural differences between the land surface models are found to be a larger source of uncertainties than differences between climate models, in particular due to different representations of soil carbon decomposition. Inertia in the permafrost carbon system means that the permafrost carbon response is dependent on the temporal trajectory of warming as well as the absolute amount of warming. We propose a new policy relevant metric – the Frozen Carbon Vulnerability timescale (FCVt) in years – that can be derived from the more complex land surface models and used to quantify the permafrost carbon response given any pathway of global temperature change.

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Formulating and testing a method for perturbing precipitation time series to reflect anticipated climatic changes

10.5194/hess-2016-500 ◽

2016 ◽

Author(s):

Hjalte Jomo Danielsen Sørup ◽

Stylianos Georgiadis ◽

Ida Bülow Gregersen ◽

Karsten Arnbjerg-Nielsen

Keyword(s):

Climate Change ◽

Time Series ◽

Climate Models ◽

Climate Change Impacts ◽

Future Climate ◽

High Temporal Resolution ◽

Urban Water ◽

Precipitation Time Series ◽

Event Scale ◽

The Impact

Abstract. Urban water infrastructure has very long planning horizons and planning is thus very dependent on reliable estimates on the impacts of climate change. Many urban water systems are designed using time series with a high temporal resolution. To assess the impact of climate change on these systems similarly high resolution precipitation time series for future climate are necessary. Climate models cannot at their current resolutions provide these time series at the relevant scales. Known methods for stochastic downscaling of climate change to urban hydrological scales have known shortcomings in constructing realistic climate changed precipitation time series at the sub-hourly scale. In the present study we present a deterministic methodology to perturb historical precipitation time series at minute scale to reflect non-linear expectations to climate change. The methodology shows good skill in meeting the expectations to climate change of extremes at event scale when evaluated at different timescales from the minute to the daily scale. The methodology also shows good skill with respect to representing expected changes to seasonal precipitation. The methodology is very robust to the actual magnitude of the expected changes as well as the direction of the changes (increase/decrease) even for situations where the extremes are increasing for seasons that in general should have a decreasing trend in precipitation. The methodology can provide planners with valuable time series representing future climate that can be used as input to urban hydrological models and give better estimates of climate change impacts on these systems.

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Modeling the impact of climate change on streamflow and major hydrological components of an Iranian Wadi system

Journal of Water and Climate Change ◽

10.2166/wcc.2020.098 ◽

2020 ◽

Author(s):

Nariman Mahmoodi ◽

Paul D. Wagner ◽

Jens Kiesel ◽

Nicola Fohrer

Keyword(s):

Climate Change ◽

Climate Models ◽

Regional Climate ◽

Regional Climate Models ◽

Hydrologic Model ◽

Low Flow ◽

Water Yield ◽

Emission Scenarios ◽

Daily Streamflow ◽

The Impact

Abstract Climate change has pronounced impacts on water resources, especially in arid regions. This study aims at assessing the impacts of climate change on streamflow of the Wadi Halilrood Basin which feeds the Jazmorian wetland in southeastern Iran. To simulate streamflow and hydrological components in the future periods (2030–2059 and 2070–2099), projections for the emission scenarios RCP4.5 and RCP8.5 from 11 global-regional climate models and two bias correction methods are used as input data for a hydrologic model that represents the daily streamflow with good accuracy (NSE: 0.76, PBIAS: 4.7, KGE: 0.87). The results indicate a slight increase of streamflow in January and March, due to the higher intensity of precipitation. However, according to the predicted flow duration curves, a decrease for high and very high flow and no remarkable changes for middle, low and very low flow is found under both emission scenarios for both future periods. Compared to the simulated hydrological components for the baseline, a slight increase of evapotranspiration of around 6 mm (4%) and 2 mm (<2%) for the mid- and end of the century is estimated, respectively. Moreover, a substantial drop of water yield of around 36 mm (63%) at mid-century and 39 mm (69%) at the end of the century are projected.

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Quantifying uncertainties of permafrost carbon–climate feedbacks

Biogeosciences ◽

10.5194/bg-14-3051-2017 ◽

2017 ◽

Vol 14 (12) ◽

pp. 3051-3066 ◽

Cited By ~ 27

Author(s):

Eleanor J. Burke ◽

Altug Ekici ◽

Ye Huang ◽

Sarah E. Chadburn ◽

Chris Huntingford ◽

...

Keyword(s):

Climate Change ◽

Land Surface ◽

Climate Models ◽

Absolute Amount ◽

Emission Scenarios ◽

Climate Feedbacks ◽

Land Surface Models ◽

Surface Models ◽

Warming World ◽

The Impact

Abstract. The land surface models JULES (Joint UK Land Environment Simulator, two versions) and ORCHIDEE-MICT (Organizing Carbon and Hydrology in Dynamic Ecosystems), each with a revised representation of permafrost carbon, were coupled to the Integrated Model Of Global Effects of climatic aNomalies (IMOGEN) intermediate-complexity climate and ocean carbon uptake model. IMOGEN calculates atmospheric carbon dioxide (CO2) and local monthly surface climate for a given emission scenario with the land–atmosphere CO2 flux exchange from either JULES or ORCHIDEE-MICT. These simulations include feedbacks associated with permafrost carbon changes in a warming world. Both IMOGEN–JULES and IMOGEN–ORCHIDEE-MICT were forced by historical and three alternative future-CO2-emission scenarios. Those simulations were performed for different climate sensitivities and regional climate change patterns based on 22 different Earth system models (ESMs) used for CMIP3 (phase 3 of the Coupled Model Intercomparison Project), allowing us to explore climate uncertainties in the context of permafrost carbon–climate feedbacks. Three future emission scenarios consistent with three representative concentration pathways were used: RCP2.6, RCP4.5 and RCP8.5. Paired simulations with and without frozen carbon processes were required to quantify the impact of the permafrost carbon feedback on climate change. The additional warming from the permafrost carbon feedback is between 0.2 and 12 % of the change in the global mean temperature (ΔT) by the year 2100 and 0.5 and 17 % of ΔT by 2300, with these ranges reflecting differences in land surface models, climate models and emissions pathway. As a percentage of ΔT, the permafrost carbon feedback has a greater impact on the low-emissions scenario (RCP2.6) than on the higher-emissions scenarios, suggesting that permafrost carbon should be taken into account when evaluating scenarios of heavy mitigation and stabilization. Structural differences between the land surface models (particularly the representation of the soil carbon decomposition) are found to be a larger source of uncertainties than differences in the climate response. Inertia in the permafrost carbon system means that the permafrost carbon response depends on the temporal trajectory of warming as well as the absolute amount of warming. We propose a new policy-relevant metric – the frozen carbon residence time (FCRt) in years – that can be derived from these complex land surface models and used to quantify the permafrost carbon response given any pathway of global temperature change.

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