Probabilistic forecasts of near-term climate change: sensitivity to adjustment of simulated variability and choice of baseline period

This study investigates the impacts of climate change on the hydrological response of a Mediterranean mesoscale catchment using a hydrological model. The effect of climate change on the discharge of the Alata River Basin in Mersin province (Turkey) was assessed under the worst-case climate change scenario (i.e., RCP8.5), using the semi-distributed, process-based hydrological model Hydrological Predictions for the Environment (HYPE). First, the model was evaluated temporally and spatially and has been shown to reproduce the measured discharge consistently. Second, the discharge was predicted under climate projections in three distinct future periods (i.e., 2021–2040, 2046–2065 and 2081–2100, reflecting the beginning, middle and end of the century, respectively). Climate change projections showed that the annual mean temperature in the Alata River Basin rises for the beginning, middle and end of the century, with about 1.35, 2.13 and 4.11 °C, respectively. Besides, the highest discharge timing seems to occur one month earlier (February instead of March) compared to the baseline period (2000–2011) in the beginning and middle of the century. The results show a decrease in precipitation and an increase in temperature in all future projections, resulting in more snowmelt and higher discharge generation in the beginning and middle of the century scenarios. However, at the end of the century, the discharge significantly decreased due to increased evapotranspiration and reduced snow depth in the upstream area. The findings of this study can help develop efficient climate change adaptation options in the Levant’s coastal areas.

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Amplified Impact of Climate Change on Fine-Sediment Delivery to a Subsiding Coast, Humboldt Bay, California

Estuaries and Coasts ◽

10.1007/s12237-021-00938-x ◽

2021 ◽

Author(s):

Jennifer A. Curtis ◽

Lorraine E. Flint ◽

Michelle A. Stern ◽

Jack Lewis ◽

Randy D. Klein

Keyword(s):

Climate Change ◽

Climate Change Impacts ◽

Baseline Period ◽

Climate Impacts ◽

Sediment Supply ◽

Balance Model ◽

Climate Projections ◽

Sediment Delivery ◽

Beneficial Reuse ◽

Coastal Margin

AbstractIn Humboldt Bay, tectonic subsidence exacerbates sea-level rise (SLR). To build surface elevations and to keep pace with SLR, the sediment demand created by subsidence and SLR must be balanced by an adequate sediment supply. This study used an ensemble of plausible future scenarios to predict potential climate change impacts on suspended-sediment discharge (Qss) from fluvial sources. Streamflow was simulated using a deterministic water-balance model, and Qss was computed using statistical sediment-transport models. Changes relative to a baseline period (1981–2010) were used to assess climate impacts. For local basins that discharge directly to the bay, the ensemble means projected increases in Qss of 27% for the mid-century (2040–2069) and 58% for the end-of-century (2070–2099). For the Eel River, a regional sediment source that discharges sediment-laden plumes to the coastal margin, the ensemble means projected increases in Qss of 53% for the mid-century and 99% for the end-of-century. Climate projections of increased precipitation and streamflow produced amplified increases in the regional sediment supply that may partially or wholly mitigate sediment demand caused by the combined effects of subsidence and SLR. This finding has important implications for coastal resiliency. Coastal regions with an increasing sediment supply may be more resilient to SLR. In a broader context, an increasing sediment supply from fluvial sources has global relevance for communities threatened by SLR that are increasingly building resiliency to SLR using sediment-based solutions that include regional sediment management, beneficial reuse strategies, and marsh restoration.

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The role of conceptual hydrologic model calibration in climate change impact on water resources assessment

Journal of Water and Climate Change ◽

10.2166/wcc.2015.086 ◽

2015 ◽

Vol 7 (1) ◽

pp. 16-28 ◽

Cited By ~ 11

Author(s):

Andrijana Todorovic ◽

Jasna Plavsic

Keyword(s):

Climate Change ◽

Climate Models ◽

Regional Climate ◽

High Sensitivity ◽

Regional Climate Models ◽

Baseline Period ◽

Hydrologic Model ◽

Calibration Period ◽

Rainfall Runoff Model ◽

Parameter Values

Assessment of climate change (CC) impact on hydrologic regime requires a calibrated rainfall-runoff model, defined by its structure and parameters. The parameter values depend, inter alia, on the calibration period. This paper investigates influence of the calibration period on parameter values, model efficiency and streamflow projections under CC. To this end, a conceptual HBV-light model of the Kolubara River catchment in Serbia is calibrated against flows observed within 5 consecutive wettest, driest, warmest and coldest years and in the complete record period. The optimised parameters reveal high sensitivity towards calibration period. Hydrologic projections under climate change are developed by employing (1) five hydrologic models with outputs of one GCM–RCM chain (Global and Regional Climate Models) and (2) one hydrologic model with five GCM–RCM outputs. Sign and magnitude of change in projected variables, compared to the corresponding values simulated over the baseline period, vary with the hydrologic model used. This variability is comparable in magnitude to variability stemming from climate models. Models calibrated over periods with similar precipitation as the projected ones may result in less uncertain projections, while warmer climate is not expected to contribute to the uncertainty in flow projections. Simulations over prolonged dry periods are expected to be uncertain.

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Effect of Climate Change on Soil Erosion in a Mountainous Mediterranean Catchment (Central Pindus, Greece)

Water ◽

10.3390/w10101469 ◽

2018 ◽

Vol 10 (10) ◽

pp. 1469 ◽

Cited By ~ 7

Author(s):

Stefanos Stefanidis ◽

Dimitrios Stathis

Keyword(s):

Climate Change ◽

Soil Erosion ◽

Potential Model ◽

Climate Model ◽

Regional Climate ◽

Baseline Period ◽

Mean Annual Temperature ◽

Temperature Changes ◽

Mountainous Catchment ◽

Precipitation And Temperature

The aim of this study was to assess soil erosion changes in the mountainous catchment of the Portaikos torrent (Central Greece) under climate change. To this end, precipitation and temperature data were derived from a high-resolution (25 × 25 km) RegCM3 regional climate model for the baseline period 1974–2000 and future period 2074–2100. Additionally, three GIS layers were generated regarding land cover, geology, and slopes in the study area, whereas erosion state was recognized after field observations. Subsequently, the erosion potential model (EPM) was applied to quantify the effects of precipitation and temperature changes on soil erosion. The results showed a decrease (−21.2%) in annual precipitation (mm) and increase (+3.6 °C) in mean annual temperature until the end of the 21st century, and the above changes are likely to lead to a small decrease (−4.9%) in soil erosion potential.

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Will Climate Change Exacerbate the Economic Damage of Flood to Agricultural Production? A Case Study of Rice in Ha Tinh Province, Vietnam

Frontiers in Environmental Science ◽

10.3389/fenvs.2021.643947 ◽

2021 ◽

Vol 9 ◽

Author(s):

Pham Quy Giang ◽

Tran Trung Vy

Keyword(s):

Climate Change ◽

Extreme Precipitation ◽

Agricultural Production ◽

Climate Change Impacts ◽

Economic Loss ◽

Baseline Period ◽

Rice Production ◽

Generalized Extreme Value Distribution ◽

Economic Damage

In developing countries in general and in Vietnam in particular, flood induced economic loss of agriculture is a serious concern since the livelihood of large populations depends on agricultural production. The objective of this study was to examine if climate change would exacerbate flood damage to agricultural production with a case study of rice production in Huong Son District of Ha Tinh Province, North-central Vietnam. The study applied a modeling approach for the prediction. Extreme precipitation and its return periods were calculated by the Generalized Extreme Value distribution method using historical daily observations and output of the MRI-CGCM3 climate model. The projected extreme precipitation data was then employed as an input of the Mike Flood model for flood modeling. Finally, an integrated approach employing flood depth and duration and crop calendar was used for the prediction of potential economic loss of rice production. Results of the study show that in comparison with the baseline period, an increase of 49.14% in the intensity of extreme precipitation was expected, while the frequency would increase 5 times by 2050s. As a result, the seriousness of floods would increase under climate change impacts as they would become more intensified, deeper and longer, and consequently the economic loss of rice production would increase significantly. While the level of peak flow was projected to rise nearly 1 m, leading the area of rice inundated to increase by 12.61%, the value of damage would rise by over 21% by 2050s compared to the baseline period. The findings of the present study are useful for long-term agricultural and infrastructural planning in order to tackle potential flooding threats to agricultural production under climate change impacts.

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The Contemporary US Energy System Overview Including A Comparison With China

Energy and Climate ◽

10.1093/oso/9780190490331.003.0007 ◽

2016 ◽

Author(s):

Michael B. McElroy

Keyword(s):

Climate Change ◽

United States ◽

Global Climate ◽

Energy System ◽

The United States ◽

Economic Benefits ◽

Personal Consumption ◽

Energy Economy ◽

Near Term ◽

Reduce Emissions

The discussion in chapter 2 addressed what might be described as a microview of the US energy economy— how we use energy as individuals, how we measure our personal consumption, and how we pay for it. We turn attention now to a more expansive perspective— the use of energy on a national scale, including a discussion of associated economic benefits and costs. We focus specifically on implications for emissions of the greenhouse gas CO2. If we are to take the issue of human- induced climate change seriously— and I do— we will be obliged to adjust our energy system markedly to reduce emissions of this gas, the most important agent for human- induced climate change. And we will need to do it sooner rather than later. This chapter will underscore the magnitude of the challenge we face if we are to successfully chart the course to a more sustainable climate- energy future. We turn later to strategies that might accelerate our progress toward this objective.We elected in this volume to focus on the present and potential future of the energy economy of the United States. It is important to recognize that the fate of the global climate system will depend not just on what happens in the United States but also to an increasing extent on what comes to pass in other large industrial economies. China surpassed the United States as the largest national emitter of CO2 in 2006. The United States and China together were responsible in 2012 for more than 42% of total global emissions. Add Russia, India, Japan, Germany, Canada, United Kingdom, South Korea, and Iran to the mix (the other members of the top 10 emitting countries ordered in terms of their relative contributions), and we can account for more than 60% of the global total. Given the importance of China to the global CO2 economy (more than 26% of the present global total and likely to increase significantly in the near term), I decided that it would be instructive to include here at least some discussion of the situation in China— to elaborate what the energy economies of China and the United States have in common, outlining at the same time the factors and challenges that set them apart.

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Projected changes in crop yield mean and variability over West Africa in a world 1.5 K warmer than the pre-industrial

10.5194/esd-2017-66 ◽

2017 ◽

Author(s):

Ben Parkes ◽

Dimitri Defrance ◽

Benjamin Sultan ◽

Philippe Ciais ◽

Xuhui Wang

Keyword(s):

Climate Change ◽

West Africa ◽

Rainwater Harvesting ◽

High Temperature Stress ◽

Climate Projections ◽

Maize Crop ◽

Crop Models ◽

Time Frequency ◽

The Mean ◽

Near Term

Abstract. The ability of a country or region to feed itself in the upcoming decades is a question of importance. The population in West Africa is expected to increase significantly in the next 30 years. The responses of food crops to short term climate change is therefore critical to the population at large and the decision makers tasked with providing food for their people. An ensemble of near term climate projections are used to simulate maize, millet and sorghum in West Africa in the recent historic and near term future. The mean yields are not expected to alter significantly, while there is an increase in inter annual variability. This increase in variability increases the likelihood of crop failures, which are defined as yield negative anomalies beyond one standard deviation during a period of 20 years. The increasing variability increases the frequency and intensity of crop failures across West Africa. The mean return frequency between mild maize crop failures from process based crop models increases from once every 6.8 years to once every 4.5 years. The mean return time frequency for severe crop failures (beyond 1.5 standard deviations) also almost doubles from once every 16.5 years to once every 8.5 years. Two adaptation responses to climate change, the adoption of heat-resistant cultivars and the use of captured rainwater have been investigated using one crop model in an idealised sensitivity test. The generalised adoption of a cultivar resistant to high temperature stress during flowering is shown to be more beneficial than using rainwater harvesting by both increasing yields and the return frequency of crop failures.

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