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Alarm Bells Continue Escalation: World Bank Warns on Climate

November 26, 2012 • Climate Change & Mitigation, Daily Email Recap

The World Bank recently released a 106 page Turn Down the Heat: Why a 4 Degree Celsius Warmer World Must be Avoided (16 MB PDF). The forward of the document, written by World Bank president, Dr. Jim Yong Kim, begins:

It is my hope that this report shocks us into action. Even for those of us already committed to fighting climate change, I hope it causes us to work with much more urgency. This report spells out what the world would be like if it warmed by 4 degrees Celsius, which is what scientists are nearly unanimously predicting by the end of the century, without serious policy changes.

The 4°C scenarios are devastating: the inundation of coastal cities; increasing risks for food production potentially leading to higher malnutrition rates; many dry regions becoming dryer, wet regions wetter; unprecedented heat waves in many regions, especially in the tropics; substantially exacerbated water scarcity in many regions; increased frequency of high-intensity tropical cyclones; and irreversible loss of biodiversity, including coral reef systems.

Jenny Goldie has provided the following highlights/excerpts.

  • In a world rapidly warming toward 4°C, the most adverse impacts on water availability are likely to occur in association with growing water demand as the world population increases. Some estimates indicate that a 4°C warming would significantly exacerbate existing water scarcity in many regions…
  • Maintaining adequate food and agricultural output in the face of increasing population and rising levels of income will be a challenge irrespective of human-induced climate change.
  • The projected impacts on water availability, ecosystems, agriculture, and human health could lead to large-scale displacement of populations and have adverse consequences for human security and economic and trade systems.
  • …a large shock to agricultural production due to extreme temperatures across many regions, along with substantial pressure on water resources and changes in the hydrological cycle, would likely impact both human health and livelihoods. This could, in turn, cascade into effects on economic development by reducing a population´s work capacity, which would then hinder growth in GDP.
  • With pressures increasing as warming progresses toward 4°C and combining with nonclimate-related social, economic, and population stresses, the risk of crossing critical social system thresholds will grow. At such thresholds existing institutions that would have supported adaptation actions would likely become much less effective or even collapse.

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