IPCC Report.pdf - Adam Curry

Chapter 4Changes in Impacts of Climate Extremes: Human Systems and Ecosystems(2005) estimated increases in damages due to extreme rainfall in TheNetherlands by mid-century.It is well known that the frequency and intensity of extreme weatherand climate events are only one factor that affects risks, as changes inpopulation, exposure of people and assets, and vulnerability determineloss potentials (see Sections 4.2 to 4.4). Few studies have specificallyquantified these factors. However, the ones that do generally underlinethe important role of projected changes (increases) in population andcapital at risk. Some studies indicate that the expected changes inexposure are much larger than the effects of climate change (see Table4-3), which is particularly true for tropical and extratropical storms(Pielke Jr., 2007; Feyen et al., 2009; Schmidt et al., 2009). Other studiesshow that the effect of increasing exposure is about as large as the effectof climate change (Hall et al., 2003; Maaskant et al., 2009; Bouwer et al.,2010), or estimate that these are generally smaller (Dorland et al., 1999;Hoes, 2007). There is therefore medium confidence that, for some climateextremes in many regions, the main driver for future increasing lossesin many regions will be socioeconomic in nature (based on mediumagreement and limited evidence). Finally, many studies underline thatboth factors need to be taken into account, as the factors do in factamplify each other, and therefore need to be studied jointly whenexpected losses from climate change are concerned (Hall et al., 2003;Bouwer et al., 2007, 2010; Pielke Jr., 2007; Feyen et al., 2009).4.5.5. Assessment of Adaptation CostsThe World Bank (2006) estimated the cost of climate-proofing foreigndirect investments, gross domestic investments, and Official DevelopmentAssistance, which was taken up and modified by Stern (2007), Oxfam(2007), and UNDP (2007). The second source of adaptation cost estimatesis UNFCCC (2007), which calculated the value of existing and plannedinvestment and financial flows required for the international communityto effectively and appropriately respond to climate change impacts. Thethird source is World Bank (2010), which also conducted a number ofcountry-level studies to complement the global assessment, followingUNFCCC (2007), but aimed at improving upon this by assessing theclimate-proofing of existing and new infrastructure, using more preciseunit cost estimates and including the costs of maintenance as well asthose of port upgrading and the risks from sea level rise and stormsurges. Also, the investment in education necessary to neutralizeimpacts of extreme weather is calculated. Estimates of costs to adapt toclimate change (rather than simply to extremes and disasters), whichhave mostly been made for developing countries, exhibit a large rangeand relate to different assessment periods (such as today, 2015, or 2030).For 2030, the estimated global cost from UNFCCC (2007) ranges fromUS$ 48 to 171 billion per year for developed and developing countries,and US$ 28 to 67 billion per year for developing countries (in 2005dollars). Recent estimates from World Bank (2010) for developingcountries lead to higher projected costs and broadly amount to theaverage of this range with annual costs of up to US$ 100 billion (in2005 US$) (see Table 4-4). Confidence in individual global estimates islow because, as mentioned above and discussed by Parry et al. (2009),the estimates are derived from only three relatively independent studies,which explains the seeming convergence of the estimates in latterstudies. As well, Parry et al. (2009) consider the estimates a significantunderestimation by at least a factor of two to three and possibly moreif the costs incurred by other sectors were included, such as ecosystemservices, energy, manufacturing, retailing, and tourism. The adaptationcost estimates are also based mostly on low levels of investment due toan existing adaptation deficit in many regions. Unavoidable residualdamages remain absent from these analyses.In terms of regional costs and as reported in the World Bank (2010)study, the largest absolute adaptation costs would arise in East Asia andthe Pacific, followed by the Latin American and Caribbean region as wellas sub-Saharan Africa. This pattern held for the two scenarios assessedTable 4-4 | Estimates of global costs of adaptation to climate change. Source: Extended based on Agrawala and Fankhauser (2008) and Parry et al. (2009).StudyResults(billion US$ yr -1 )Time Frame andCoverageSectorsMethodology and CommentWorld Bank (2006) 9–41 1Stern (2007) 4–37 1Oxfam (2007) >50 1UNDP (2007) 86–109 2UNFCCC (2007)48–171(28–67 fordevelopingcountries) 2World Bank (2010) 70–100 2Present, developingcountriesPresent, developingcountriesPresent, developingcountriesIn 2015, developingcountriesIn 2030, developedand developingcountriesAnnual from 2010to 2050, developingcountriesUnspecifiedUnspecified Update of World Bank (2006)UnspecifiedUnspecifiedAgriculture, forestry, and fisheries; watersupply; human health; coastal zones;infrastructure; ecosystems (but no estimatefor 2030 for ecosystem adaptation)Agriculture, forestry, and fisheries; watersupply and flood protection; human health;coastal zones; infrastructure; extremeweather eventsCost of climate-proofing foreign direct investments, gross domesticinvestments, and Official Development AssistanceWorld Bank (2006) plus extrapolation of cost estimates from NationalAdaptation Programmes of Action and NGO projectsWorld Bank (2006) plus costing of targets for adapting poverty reductionprograms and strengthening disaster response systemsAdditional investment and financial flows needed for adaptation in 2030Impact costs linked to adaptation costs, improvement upon UNFCCC(2007): climate-proofing existing and new infrastructure, more preciseunit cost, inclusion of cost of maintenance and port upgrading, risksfrom sea level rise and storm surges, riverine flood protection, educationinvestment to neutralize impacts of extreme weather eventsNotes: 1. in 2000 US$; 2. in 2005 US$.273