Differences between low-end and high-end climate change impacts across multiple sectors: what does this mean for adaptation?

16:15 Wednesday 29 May

OC181

Room S6

 

Paula Harrison (United Kingdom) 1; Robert Dunford (United Kingdom) 1; Ian Holman (United Kingdom) 2; George Cojocaru (Romania) 3; Marianne Madsen (Denmark) 4; Pei-Yuan Chen (United Kingdom) 1

1 - Centre for Ecology & Hydrology; 2 - Cranfield University; 3 - TIAMASG; 4 - Danish Meterological Institute

The Paris Agreement has set an international policy agenda towards achieving low-end climate change, i.e. limiting global temperature increases to ‘well below 2°C above pre-industrial levels’ and ‘to pursue efforts to limit the temperature increase to 1.5°C’. The 1.5oC and 2oC policy targets under the Paris Agreement were established based on the recognition ‘that this would significantly reduce the risks and impacts of climate change’. However, few studies have compared impacts of low-end (less than 2oC) and high-end (greater than 4oC) climate change for a wide range of sectors.

This presentation aims to show how climate change impacts and vulnerabilities differ in worlds where the Paris Agreement is met compared to worlds where climatic change is largely ignored leading to high-end scenarios. It will show when the benefits of emissions reductions, in terms of significantly reducing impacts, become apparent given scenario uncertainties. It will also assess how the different climate futures interact with different socio-economic futures to produce different spatial patterns and magnitudes of impacts. In doing so it presents the first cross-sectoral picture of the implications of meeting (or not meeting) the Paris Agreement for Europe’s future and highlights the complex interdependencies between climate and society.

A regional integrated assessment model that captures interactions between six sectors (agriculture, forests, biodiversity, water, coasts and urban) was used to investigate impacts resulting from low-end climate change scenarios (as represented by Representative Concentration Pathway (RCP) 2.6) and high-end climate change scenarios (as represented by RCP 8.5). Furthermore, it is applied to examine how the different climate futures (RCPs 2.6 and 8.5) interact with different socio-economic futures (as represented by the Shared Socioeconomic Pathways, SSPs) to produce different sectoral and cross-sectoral challenges for adaptation and different winners and losers.

Substantially greater impacts are projected for all European regions under high-end than low-end climate change, with large shifts in land use under high-end climate change leading to significant challenges for adaptation with regard to agricultural and forest productivity, water stress, flooding and biodiversity vulnerability. Including changes in socio-economic conditions results in much greater magnitudes of changes in the majority of impact indicators than climate change alone. This provides essential information on climate change impact uncertainties that are needed for developing an appropriate mix of adaptation and mitigation strategies. Such insight builds the capacity of decision-makers to understand the cross-sectoral climate change vulnerability, highlighting the need to mainstream adaptation across sectors and policies.