A Price to Pay

As the penultimate post, I thought I'd start to round off the blog by talking about the economics of adaption - just how much is it going to cost to adapt human water systems to the changes to the hydrological cycle that will likely occur over the next 50 years? Calculating such global costs for the water sector is clearly not a simple task, and there is no trace of certainty in any numbers that have been produced. However, they are figures that are hopefully indicative of the scale of the changes the world will face.

Kirshen (2007) estimates the global cost (more than 200 countries) of maintaining water services at current levels through to 2030 under a medium emissions scenario to be US$531 billion. The United Nations Framework Convention on Climate Change (2007) suggest a figure US$225 billion s (approximately US$11 billion per year), for the same emissions scenario. These are incredibly large numbers - US$11 billion is the equivalent of China's 2016 GDP, and this is only the annual cost of adapting the water sector to maintain water services until 2030!

Looking forward to the year 2050, Ward et al. (2010) use suggest average annual costs of US$19.7 billion (in a drier projection of climate) and US$14.4 billion (in a wetter projection of climate) to maintain current global water supply and flood protection. These numbers were derived by using a global climate model (GCM) to make climate projections, and estimating costs based on the projections. Once again, big numbers.

Perhaps of special interest in addressing the costs of hydrological climate change is sub-Saharan Africa. This is a region that will be particularly affected by climate change, and is a region of the world where many live in poverty. While they are now outdated, having been succeeded with Sustainable Development Goals (SDGs) for 2030, the 2015 Millennium Development Goals have been used to assess the cost of adoption to hydrological climate change in sub-Saharan Africa. Muller (2007) suggests an annual cost for the adaptation of urban water infrastructure of US$1.1 to 2.7 billion to, with an additional $1.0 to 2.5 billion required to upgrade infrastructure to meet the Millennium Development Goals. Clearly these figures are now approaching 10 years out of date, and do not reflect current development targets nor economic changes since then, but they are still useful. The countries of sub-Saharan Africa are amongst the poorest in the world, and will likely struggle to fund such costs. Given the sensitivity and current state of the region, some amount of aid on behalf of the rest of the world is going to be needed here.

I hope this post helps put the financial scale of hydrological climate change in some sort of context, even if it does just address the adaptation of  water infrastructure and makes no reference to the costs of other hydrological changes. While the numbers are very large, please do take them with a pinch of salt; there is obviously no way to be at all sure what the costs will be, and they are very much just estimates. However, they do make a clear point - this is an expensive issue. Humans die without a reliable supply of clean water, so much expense is will have to be paid. Quite as to who will pay is the question, particularly in the case of the poorer area of the world.