Temperature to rise by 4°C with current C02 targets

Without further commitments to reduce greenhouse gas emissions the world will see temperatures rise by four degrees and experience extreme heat-waves, declining global food stocks and sea levels rise, according to a report by the World Bank.

The World Bank’s analysis, Turn Down the Heat: Why a 4°C Warmer World Must Be Avoided, says scientists are predicting that today’s climate could warm from the current global mean temperature of 0.8°C above pre-industrial levels, to as high as 4°C by 2100, even if countries fulfil current emissions-reduction targets.

“Lack of action on climate change threatens to make the world our children inherit a completely different world than we are living in today. Climate change is one of the single biggest challenges facing development, and we need to assume the moral responsibility to take action on behalf of future generations, especially the poorest,” said World Bank Group President Jim Yong Kim.

Even with current mitigation commitments and pledges fully implemented, the report claims that there is roughly a 20% likelihood of exceeding 4°C by 2100.

However, if commitments are not met, a warming of four degrees could occur as early as the 2060s, the report states.

“Such a warming level and associated sea-level rise of 0.5 to 1 meter, or more, by 2100 would not be the end point: a further warming to levels over 6°C, with several meters of sea-level rise, would likely occur over the following centuries,” it adds.

Despite warning that “no nation will be immune to the impacts of climate change”, the report suggests that distribution of impacts is likely to be inherently unequal and tilted against many of the world’s poorest regions, which have the least economic, institutional, scientific, and technical capacity to cope and adapt.

“A world in which warming reaches 4°C above preindustrial levels (hereafter referred to as a 4°C world), would be one of unprecedented heat waves, severe drought, and major floods in many regions, with serious impacts on human systems, ecosystems, and associated services,” it continues.

However, the report suggests that warming of 4°C can still be avoided with numerous studies showing that there are technically and economically feasible emissions pathways to hold warming below 2°C.

“Thus the level of impacts that developing countries and the rest of the world experience will be a result of government, private sector, and civil society decisions and choices, including, unfortunately, inaction2 the report adds.

Earlier in November, PriceWaterHouseCoopers (PwC) said doubling the current rate of decarbonisation would still lead to emissions consistent with six degrees of warming by the end of the century.

It added that the required improvement in global carbon intensity to meet a 2°C warming target, has risen to 5.1% a year, from 2012 to 2050.

“To give ourselves a more than 50% chance of avoiding two degrees will require a six-fold improvement in our rate of decarbonisation”.

Leigh Stringer

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