Turning back the tide? Local‐scale impacts of climate change may have positive effects by restoring natural riverine habitat and reducing invasive fish density

Abstract. Climate models project increases in globally averaged atmospheric specific humidity that are close to the Clausius–Clapeyron (CC) value of around 7% K−1 whilst projections for mean annual global precipitation (P) and evaporation (E) are somewhat muted at around 2% K−1. Such global projections are useful summaries but do not provide guidance at local (grid box) scales where impacts occur. To bridge that gap in spatial scale, previous research has shown that the "wet get wetter and dry get drier" relation, Δ(P − E) &propto; P − E, follows CC scaling when the projected changes are averaged over latitudinal zones. Much of the research on projected climate impacts has been based on an implicit assumption that this CC relation also holds at local (grid box) scales but this has not previously been examined. In this paper we find that the simple latitudinal average CC scaling relation does not hold at local (grid box) scales over either ocean or land. This means that in terms of P − E, the climate models do not project that the "wet get wetter and dry get drier" at the local scales that are relevant for agricultural, ecological and hydrologic impacts. In an attempt to develop a simple framework for local-scale analysis we found that the climate model output shows a remarkably close relation to the long-standing Budyko framework of catchment hydrology. We subsequently use the Budyko curve and find that the local-scale changes in P − E projected by climate models are dominated by changes in P while the changes in net irradiance at the surface due to greenhouse forcing are small and only play a minor role in changing the mean annual P − E in the climate model projections. To further understand the apparently small changes in net irradiance we also examine projections of key surface energy balance terms. In terms of global averages, we find that the climate model projections are dominated by changes in only three terms of the surface energy balance: (1) an increase in the incoming long-wave irradiance, and the respective responses (2) in outgoing long-wave irradiance and (3) in the evaporative flux, with the latter change being much smaller than the former two terms and mostly restricted to the oceans. The small fraction of the realised surface forcing that is partitioned into E explains why the hydrologic sensitivity (2% K−1) is so much smaller than CC scaling (7% K−1). Much public and scientific perception about changes in the water cycle has been based on the notion that temperature enhances E. That notion is partly true but has proved an unfortunate starting point because it has led to misleading conclusions about the impacts of climate change on the water cycle. A better general understanding of the potential impacts of climate change on water availability that are projected by climate models will surely be gained by starting with the notion that the greater the enhancement of E, the less the surface temperature increase (and vice versa). That latter notion is based on the conservation of energy and is an underlying basis of climate model projections.

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Risk assessment of possible impacts of climate change and irrigation on wheat yield and quality with a modified CERES-Wheat model

Journal of Water and Climate Change ◽

10.2166/wcc.2021.248 ◽

2021 ◽

Author(s):

Jianchao Liu

Keyword(s):

Climate Change ◽

Risk Assessment ◽

Meteorological Data ◽

Wheat Yield ◽

Climate Change Scenarios ◽

Effective Measure ◽

Climatic Regions ◽

Positive Effects ◽

Yield And Quality ◽

Impacts Of Climate Change

Abstract The effects of climate change on yield and quality in different climate regions have high uncertainty. Risk assessment is an effective measure to assess the seriousness of the projected impacts for decision-makers. A modified quality model was used to simulate integrated impacts of climate change, environment, and management on wheat yield and quality. Then, the Canadian Earth System Model version 5 (CanESM5) was used to forecast the daily meteorological data, and the Statistical Downscaling Model (SDSM V5.2) was used for downscaling. The modified CERES-Wheat was combined with the forecasted meteorological data to simulate the future wheat yield and grain protein concentration (GPC). The risk to wheat yield and quality in three climatic regions in Northwest China under two climate change scenarios of the CanESM5 was assessed. The average temperature increased by 0.22–3.34 °C, and precipitation increased by 10–60 mm from 2018 to 2100. Elevated temperature and precipitation had positive effects on the yields. The risk to yield in most regions with climate change decreased by 3.8–25.1%. The risk to GPC in all regions with climate change decreased by 7.3–27.2%. Irrigation decreased the risk to yield greatly but had different effects in the three climatic regions. The risk to yield with irrigation decreased by 37.7–52.1%. In contrast to previous studies, in this study, the risk to GPC with irrigation substantially increased by 25.8–28.9% in humid regions and 3.9–8.8% in subhumid regions and decreased by 37.7–52.1% in semiarid regions. The irrigation should be discreetly applied for different climatic regions to combat climate change.

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Possible Impacts of Climate Change on Daily Streamflow and Extremes at Local Scale in Ontario, Canada. Part I: Historical Simulation

Atmospheric and Climate Sciences ◽

10.4236/acs.2012.24036 ◽

2012 ◽

Vol 02 (04) ◽

pp. 416-426 ◽

Cited By ~ 1

Author(s):

Chad Shouquan Cheng ◽

Qian Li ◽

Guilong Li ◽

Heather Auld

Keyword(s):

Climate Change ◽

Local Scale ◽

Historical Simulation ◽

Daily Streamflow ◽

Impacts Of Climate Change

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The Economic Impacts of Climate Change: Evidence from Agricultural Output and Random Fluctuations in Weather

The American Economic Review ◽

10.1257/aer.97.1.354 ◽

2007 ◽

Vol 97 (1) ◽

pp. 354-385 ◽

Cited By ~ 498

Author(s):

Olivier Deschênes ◽

Michael Greenstone

Keyword(s):

Climate Change ◽

Economic Impact ◽

Agricultural Land ◽

Economic Impacts ◽

Impact Of Climate Change ◽

Positive Effects ◽

Temperature And Precipitation ◽

Random Fluctuations ◽

Hedonic Approach ◽

Impacts Of Climate Change

This paper measures the economic impact of climate change on US agricultural land by estimating the effect of random year-to-year variation in temperature and precipitation on agricultural profits. The preferred estimates indicate that climate change will increase annual profits by $1.3 billion in 2002 dollars (2002$) or 4 percent. This estimate is robust to numerous specification checks and relatively precise, so large negative or positive effects are unlikely. We also find the hedonic approach—which is the standard in the previous literature—to be unreliable because it produces estimates that are extremely sensitive to seemingly minor choices about control variables, sample, and weighting. (JEL L25, Q12, Q51, Q54)

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Climate Change in Oceania – A synthesis of biodiversity impacts and adaptations.

Pacific Conservation Biology ◽

10.1071/pc110270 ◽

2011 ◽

Vol 17 (3) ◽

pp. 270 ◽

Cited By ~ 20

Author(s):

Richard T Kingsford ◽

James E M Watson

Keyword(s):

Climate Change ◽

Pacific Islands ◽

Climate Adaptation ◽

Local Scale ◽

Considerable Uncertainty ◽

Management Processes ◽

Geographical Regions ◽

The World ◽

Future Challenges ◽

Impacts Of Climate Change

Climate change is already affecting many of the world’s ecosystems with far-reaching impacts. In this special issue, contributors focus on the current and projected impacts of climate change across different geographical regions of Oceania (Australia, Pacific Islands and New Zealand). In this synthesis, we examine how climate change is affecting the three main realms: terrestrial, freshwater (broadly including estuarine and inland saline systems) and marine. Within this context, we also examine general strategies for climate adaptation including reducing other threats (e.g., habitat loss and degradation), expanding protected areas, increasing connectivity, restoring habitat and translocations. We show that many of these general strategies will not overcome all the threats caused by climate change and specific solutions are likely to be necessary. Beyond the implementation of these strategies, there are significant future challenges which will hamper effective adaptation that need to be overcome by the scientific community. Our current understanding of the impacts of climate change on biodiversity remains poor; this is particularly true for poor nations in the region. There is also considerable uncertainty in forecasts of climate change, particularly at the local scale, and this uncertainty impacts pro-active planning. This makes effective implementation particularly challenging. Considerable focus is needed into ecosystem-based adaptation where local communities are integrally involved, allied with more active and accountable management of conservation, through adaptive management processes. The world is experiencing far reaching and long-term changes to ecosystems with major impacts on human communities, particularly in relation to ecosystem services. Our ability to develop effective adaptation strategies from the broad scale policy (e.g., emissions control) to local scale management (e.g., building resilience in ecosystems) will be significantly tested but the world is in an important period and scientists and practitioners need to keep trying different approaches and reporting their successes and failures to the wider community.

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Possible impacts of climate change on extreme weather events at local scale in south–central Canada

Climatic Change ◽

10.1007/s10584-011-0252-0 ◽

2011 ◽

Vol 112 (3-4) ◽

pp. 963-979 ◽

Cited By ~ 28

Author(s):

Chad Shouquan Cheng ◽

Heather Auld ◽

Qian Li ◽

Guilong Li

Keyword(s):

Climate Change ◽

Extreme Weather ◽

Local Scale ◽

Extreme Weather Events ◽

South Central ◽

Weather Events ◽

Central Canada ◽

Impacts Of Climate Change

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Vulnerability and Adaptation of Coastal Livelihoods to the Impacts of Climate Change: A Case Study in Coastal Districts of Nam Dinh, Vietnam

Journal of Economics and Development ◽

10.33301/2014.16.02.03 ◽

2014 ◽

pp. 39-60 ◽

Cited By ~ 1

Author(s):

Dat Tran Tho ◽

Thu Vu Thi Hoai ◽

Toan Pham Ngoc

Keyword(s):

Climate Change ◽

Physical Capital ◽

Vital Role ◽

Livelihood Strategies ◽

Positive Effects ◽

Livelihood Assets ◽

The Government ◽

Coastal Livelihoods ◽

Impacts Of Climate Change

Communities in coastal areas tend to be dependent on climate sensitive resources for their livelihoods which make them vulnerable to the impacts of climate change. Livelihood adaptation plays a vital role in mitigating vulnerabilities, increasing resilience, and achieving sustainable income and food security in the long term. Drawing on quantitative data from a case study in three coastal districts of Nam Dinh province in Vietnam, this paper investigates vulnerability and adaptation of coastal livelihoods to the impacts of climate change at a household level. Findings suggest that (i) climate change has positive effects on livelihood assets, especially natural and physical capital; (ii) the more livelihood assets are affected by climate change, the more livelihood strategies are affected; (iii) the more livelihood strategies are affected by climate change, the more livelihood outcomes are affected, and (iv) households are implementing passive adaptation activities on their livelihoods rather than active ones to counter the impacts of climate change. It is recommended that in order to help households successfully adapt to the impacts of climate change, it is necessary for the government to support households to improve their livelihood assets, especially natural and physical capital, and to enhance institutions and policies on climate change adaptation at national and local levels.

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