Chapter 8   Costing Climate Change

 by Alan Moran

 

The IPCC’s three voluminous ‘Fifth Assessment’ Working Group reports and their slimmed-down Summaries for Policymakers were completed in 2013 and 2014. To condense the findings of what is said to be the work of 803 authors, the IPCC estimates that a doubling of atmospheric carbon dioxide (CO2 ) will cause warming between 1.5°C and 4.5°C. Perhaps in response to seventeen years in which the planet has defied the warming forecasts of climate models, the lower boundary was reduced in the latest assessment. This did not however prevent the decibels of commentary about adverse implications being cranked up.

 

Highly respected climate scientists put the likely warming below the bottom of the IPCC range. Writing in this volume, Richard Lindzen estimates the maximum warming possible for human induced greenhouse gases is 1°C, while Beenstock, Reingewertz and Paldor find that the relationship between greenhouse gases and warming is spurious except perhaps in the short term.

 

Entertainers urge us to reduce consumption of non-renewable energy in order to forestall adverse effects of global warming. Ironically some of these exhorters have carbon footprints many times those of common folk— Bono’s 2010 world concert tour is estimated to have generated emissions equivalent to the annual level of 6,500 British people. 

 

 

How much will climate change hurt?

The key questions are, ‘How much damage will emanate from the likely atmospheric doubling of carbon dioxide and other greenhouse gases?’ and, ‘What is the cost of measures to prevent this doubling?’ The IPCC puts the qualitative costs of warming in the following foreboding terms:

• Each degree of warming is projected to decrease renewable water resources by at least twenty per cent for an additional seven per cent of the global population.

• Climate change is likely to increase the frequency of droughts.

• Heavy rainfalls are likely to become more intense and frequent.

• In response to further warming by 1°C or more by the mid-twenty-first century and beyond, ocean-wide changes in ecosystem properties are projected to continue, with implications for food security.

• Urban climate change risks, vulnerabilities, and impacts are increasing across the world in urban centres of all sizes, economic conditions, and site characteristics. Climate change will have profound impacts on a broad spectrum of infrastructure systems (water and energy supply, sanitation and drainage, transport and telecommunication), services (including health care and emergency services), the built environment and ecosystem services.

• Climate trends are affecting the abundance and distribution of harvested aquatic species, both freshwater and marine, and aquaculture production systems in different parts of the world but with benefits in other regions.

• Without adaptation, local temperature increases in excess of about 1°C above pre-industrial is projected to have negative effects on yields for the major crops (wheat, rice and maize) with increased global food prices by 2050.

 

In fleshing out these generalities, the IPCC maintains that climate change is already impacting on natural and human systems. It says these effects include changing precipitation, melting snow and diminishing crop yields.

 

The Working Group II report sees additional costs being derived from the following key risks: 

 

• Risk of death, injury, ill-health, or disrupted livelihoods in low-lying coastal zones and small island developing states and other small islands, due to storm surges, coastal flooding, and sea-level rise.

• Risk of severe ill-health and disrupted livelihoods for large urban populations due to inland flooding in some regions.

• Systemic risks due to extreme weather events leading to breakdown of infrastructure networks and critical services such as electricity, water supply, and health and emergency services.

• Risk of mortality and morbidity during periods of extreme heat, particularly for vulnerable urban populations and those working outdoors in urban or rural areas.

• Risk of food insecurity and the breakdown of food systems linked to warming, drought, flooding, and precipitation variability and extremes, particularly for poorer populations in urban and rural settings.

• Risk of loss of rural livelihoods and income due to insufficient access to drinking and irrigation water and reduced agricultural productivity, particularly for farmers and pastoralists with minimal capital in semiarid regions.

• Risk of loss of marine and coastal ecosystems, biodiversity, and the ecosystem goods, functions, and services they provide for coastal livelihoods, especially for fishing communities in the tropics and the Arctic.

• Risk of loss of terrestrial and inland water ecosystems, biodiversity, and the ecosystem goods, functions, and services they provide for livelihoods.