The Impact of Climate Change on Natural Disasters - Reducing Disaster: Early Warning Systems for Climate Change - page 37

America in 2008 was mostly due to cooling sea surface temperatures in the tropical
Pacifi c, which is part of natural ocean variability. They, however, also found that the
cooling was partially offset by the ongoing human warming impact on the climate.

2.3.4 Outlook

Extreme events can be destructive and knowing what causes them is a major public
interest (Schiermeier 2011 ).
As past studies have shown, some extreme weather events are not wholly or even
partly attributable to human-induced climate change, as many other factors are playing
roles as well (i.e., Lott et al. 2013 ; Perlwitz et al. 2009 ).
Being able to attribute extreme events to climate change is valuable from litiga-
tion, insurance, and adaptation points of view. The risk of misattribution of events,
however, looms large. Incorrectly attributing events to climate change can lead to
public confusion about climate change and limit public and political support for
investment in disaster risk reduction and climate change adaptation (Stott et al.
2011 ; Donner 2012 ). Even in a case where it can be shown that human infl uence
leads to a higher probability of occurrence of a certain type of event, the probability
of that event is not necessarily the same every year (Peterson et al. 2012 ).
Despite these limitations, there remains great potential for future advancement in
event attribution research. Rather than examining only temperature or precipitation
anomalies, attribution researchers may fi nd higher statistical confi dence by focusing
on other climate variables or on atmosphere and ocean dynamics.
For example, most of the research on Atlantic hurricanes has focused on forcing
from ocean temperatures and storm intensity. Estimating the role of anthropogenic cli-
mate change in the formation of an individual Atlantic hurricane like Sandy, or the fre-
quency of hurricanes like Sandy, is limited by the complex array of factors that infl uence
hurricane development. Alternatively, looking beyond ocean temperatures, and examin-
ing the unique path of Hurricane Sandy and record storm surge in New York City may
present additional opportunities for attribution research. First, Hurricane Sandy made
landfall in the United States because a strong high pressure system forced the oceanic
storm to make an unusually sharp westward turn - and anti-Coriolis left turn. Attribution
research could build upon recent fi ndings that prolonged “blocking” high pressure sys-
tems are expected to be more common (Trenberth and Fasullo 2012 ), especially in
North America due to the climate-driven decline in Arctic sea ice cover (Francis and
Vavrus 2012 ). Second, Sandy created a record storm surge at New York City's Battery
Park gauge, for which sea levels have increased on average by 40 cm since the late
1880s due to climate change and land subsidence (NPCC 2010 ). Attribution research
could examine the relative contribution of sea-level rise to the storm surge and wave
run-up at individual locations using climate and hydrodynamic models.
Different perspectives that try to connect the infl uence of teleconnections and the
relationship between events as well as to understand the environment in which the
extreme events are happening may prove relevant for future event attribution
research (Trenberth and Fasullo 2012 ).