Abstract: Working Group II contribution to the IPCC Fifth Assessment Report (AR5) presents new findings of cross-regional impacts of climate change. In Africa, climate change will amplify existing stress on water availability and on agricultural systems particularly in semi-arid environments. In Europe, climate change will increase the likelihood of systemic failures across European countries caused by extreme climate events affecting multiple sectors. In Asia, climate change will cause declines in agricultural productivity in many subregions of Asia, for crops such as rice. In Australasia, without adaptation, further changes in climate, atmospheric CO₂ and ocean acidity are projected to have substantial impacts on water resources, coastal ecosystems, infrastructure, health, agriculture and biodiversity. In North America, many climate-related hazards which carry risk, particularly related to severe heat, heavy precipitation, and declining snowpack, will increase in frequency and/or severity in the next decades. In Central and South America, despite improvements, high and persistent levels of poverty in most countries result in high vulnerability to climate variability and change. In the Arctic, climate change and often-interconnected non-climate-related drivers, including environmental changes, demography, culture, and economic development, interact to determine physical, biological and socioeconomic risks, with rates of change that may be faster than social systems can adapt. Small islands have high vulnerability to climatic and non-climatic stressors. Warming will increase risks to ocean ecosystems.

Key words: climate change, regional impact, IPCC AR5