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

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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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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Climate Change Adaptation Policy Guidelines for Agricultural Sector in Malaysia

10.31219/osf.io/3snja ◽

2019 ◽

Author(s):

Md. Mahmudul Alam ◽

Chamhuri Siwar ◽

Abul Quasem Al-Amin

Keyword(s):

Climate Change ◽

Climatic Change ◽

Agricultural Sector ◽

Local Scale ◽

Agricultural Sustainability ◽

Adaptation Policy ◽

Future Risk ◽

Different Levels ◽

Impacts Of Climate Change

Climate Projection shows the impacts of climate change on agricultural sustainability and relevant livelihood sustainability is vulnerable in Malaysia. Here mitigation is necessary but adapting to future risk is more important for immediate and long term action relating to the larger number of stakeholders in local scale. Generally adaptation policy has different levels and approaches that related with different challenges. Several countries have already prepared their adaptation approaches in their own way. Malaysia is on the way to develop its adaptation policy for last couple of years. This paper focuses on few guidelines that need to examine carefully while determining the climatic change adaptation approach for agricultural sector in Malaysia.

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