Naturskader som økonomisk og klimapolitisk interessesfæreDet som i engelsk ordbruk kalles "disaster losses" (store naturskadetap) er et yndet tema for bl.a.
forsikringsselskapene, som med henvisning til dystre fremskrivninger av kostnadsbilder mener de må legge på premiene.
Likevel, skremsler om store framtidige naturkatastrofer (underforstått: forårsaket av menneskelig aktivitet) er et enda mer yndet tema hos de mest uetterrettelige
klimaalarmistene.
Vi har derfor to "klassiske" scenarier der disse to interessegruppene lett begår en rekke analytiske kortslutninger før vitenskapelige trendanalyser i det hele tatt foretas:
1. Når uværet treffer et tidligere ubebygd område og øker skadekostnadeneStore naturskade
kostnader forårsaket av vær- og klimaforhold øker med økt urbanisering, fortetting av infrastruktur osv.
selv om vær- og klimatrender holdes uendret, utlagt: Forsikringsselskapene opplever stadig større erstatningsbehov i store og voksende infrastrukturer enn i grisgrendte, uutbygde strøk, og må selvsagt justere premiene sine iht. denne samfunnsutviklingen.
Men: Disse økte kostnadene sier selvsagt ingen ting om vær- og klimatrend i isolert naturvitenskapelig forstand, de sier i beste fall noe om i hvor stor grad uvær har truffet sentrale strøk - forsikringsselskapene kan derfor ikke seriøst bruke naturvitenskapelig trendmateriale i sine premievurderinger da disse ikke sier noe om sannsynligheten for hva som berøres: Man kan f.eks. oppleve at en periodisk økende uværstrend skjer parallelt med at mindre infrastruktur rammes og kostnadene går ned - eller omvendt.
2. Når alt uvær relateres til menneskeskapte klimaendringerVi har over mange år sett at de mest uetterrettelige og sensasjonsfokuserte klimaalarmistene viser til enhver naturkatastrofe som forårsaket av "menneskeskapte klimaendringer", her er det nok å vise til den overdådig morsomme listen man finner her om "A (Not Quite) Complete List Of Things Supposedly Caused By Global Warming":
http://whatreallyhappened.com/WRHARTICLES/globalwarming2.htmlMerk at disse innledende punktene om analytiske feilkilder har direkte relevans til diskusjonen om "vulnerability"-problematikken i paperet som presenteres nedenfor, om der kan påvises en trend for klimaendringer versus store naturskader?
Nytt paper: "On the relation between weather-related disaster impacts, vulnerability and climate change"Denne uken slapp
Climatic Change et paper av Visser et al. som ser på forholdet mellom naturkatastrofer og klimaendringer. For å ta det viktigste først:
Visser et al. ser på en rekke metrikker (metrikk: en funksjon som definerer en avstand eller distanse mellom to elementer i en mengde) for økonomiske og menneskelige tap, men
finner ingen trender for "normalized disaster losses".
Hele arbeidet kan studeres her:
http://link.springer.com/article/10.1007/s10584-014-1179-z/fulltext.htmlNoen konklusjoner:
The absence of trends in normalized disaster burden indicators appears to be largely consistent with the absence of trends in extreme weather events. This conclusion is more qualitative for the number of people killed. As a consequence, vulnerability is also largely stable over the period of analysis.Det som sies i den understrekede første setningen her er for øvrig konsistent med tidligere data og analyser hos bl.a. Bouwer 2011, Neumayer & Bartel 2011, Mohleji & Pielke 2014, og siste IPCC-rapport (SREX og AR5).
Roger Pielke Jr. har forresten en interessant kommentar om Visser et als diskusjon om sårbarhet (vulnerability), med denne innledende selverkjennelsen:
"Some have argued that our methodological inability to fully account for possible changes in vulnerability to losses over time may mask a climate change signal in the data. (It's gotta be there somewhere!) This line of argument has always been suspect, because there are not relevant trends in phenomena such as floods and hurricanes which would lead to an expectation of increasing normalized losses." Pielke Jr. viser så hvordan Visser et al. har tatt tak i denne utfordringen og gir flere forklaringer på hvorfor sårbarhet ikke skal kunne maskere evt. "hidden signals":
Firstly, global disaster management initiatives have only recently been put in place. The Hyogo Framework for Action (HFA) was adopted by 168 Member States of the United Nations in 2005 to take action to reduce vulnerabilities and risks to disasters (UNISDR, 2011). Although these highly important efforts will certainly pay off in the near future, it is unclear whether they are reflected in the sample period chosen for this study. Similar conclusions are drawn in IPCC (2014). . . Secondly, it is unclear to what extent adaptation measures work in practice. Heffernan (2012) argues that many countries, and even the richest, are ill-prepared for weather extremes. As an example, he names Hurricane Sandy, which wreaked a loss of 50 billion USD along the northeast coast of the US in 2012. As for early warning systems, Heffernan states that not all systems are functioning well. For example, in 2000, Mozambique was hit by a flood worse than any in its history, and the event was not at all anticipated. Warnings of above-average rainfall came too late and failed to convey the magnitude of the coming flood.Thirdly, a positive trend in vulnerability may be offset by the increasing number of people moving from rural to urban environments, often situated in at-risk areas (UN 2012). Since many large cities lie along coastlines, these movements will make people more vulnerable to land-falling hurricanes (Pielke et al. 2008), coastal flooding and heatwaves (due the urban heat island effect). With regard to economic losses, Hallegatte (2011) argues that these migration movements may have caused disaster losses to grow faster than wealth.Fourthly, it is unclear how political tensions and violent conflicts have evolved over large regional scales since 1980. On the one hand, Theisen et al. (2013) show that the number of armed conflicts and the number of battle deaths have decreased slightly at the global scale since 1980. On the other hand, these methods are rather crude as far as covering all aspects of political tensions are concerned (Leaning and Guha-Sapir et al. 2013).Visser et all sier derfor at de konkluderer at:
We conclude that quantitative information on time-varying vulnerability patterns is lacking. More qualitatively, we judge that a stable vulnerability V t, as derived in this study, is not in contrast with estimates in the literature.Pielke Jr. oppsummerer sin kommentar så tydelig at det bør glede alle som river seg i håret over alarmistenes monomane hamring på det motsatte:
The bottom line? Once again, we see further reinforcement for the conclusion that there is no detectable evidence of a role for human-caused climate change in increasing disaster losses. In plain English: Disaster losses have been increasing, but it is not due to climate change. Link:
http://rogerpielkejr.blogspot.no/Til avslutning, her er abstractet:
AbstractDisasters such as floods, storms, heatwaves and droughts can have enormous implications for health, the environment and economic development. In this article, we address the question of how climate change might have influenced the impact of weather-related disasters. This relation is not straightforward, since disaster burden is not influenced by weather and climate events aloneâ??other drivers are growth in population and wealth, and changes in vulnerability.
We normalized disaster impacts, analyzed trends in the data and compared them with trends in extreme weather and climate events and vulnerability, following a 3 by 4 by 3 set-up, with three disaster burden categories, four regions and three extreme weather event categories. The trends in normalized disaster impacts show large differences between regions and weather event categories. Despite these variations, our overall conclusion is that the increasing exposure of people and economic assets is the major cause of increasing trends in disaster impacts. This holds for long-term trends in economic losses as well as the number of people affected. We also found similar, though more qualitative, results for the number of people killed; in all three cases, the role played by climate change cannot be excluded. Furthermore, we found that trends in historic vulnerability tend to be stable over time, despite adaptation measures taken by countries.
Based on these findings, we derived disaster impact projections for the coming decades. We argue that projections beyond 2030 are too uncertain, not only due to unknown changes in vulnerability, but also due to increasing non-stationarities in normalization relations.