Climate change futures: health, ecological and economic dimensions

68 | NATURAL AND MANAGED SYSTEMS
CASE STUDIES
THE 1997/98 EL NIÑO EVENT
Concerns over the fire-related consequences of global
warming were rekindled in 1998 by the impacts of the
El Niño of 1997/98, the strongest of the 20th century.
This was part of the anomalous period from 1976-98
with an increased frequency, intensity and duration of El
Niño events, based on records dating back to 1887.
The powerful impact that climatic anomalies can have
was demonstrated after droughts linked to El Niño were
followed by widespread, devastating fires in Southeast
Asia and Brazil, each taking enormous tolls in terms of
acute and chronic respiratory diseases. In the US,
Florida experienced a rash of wildfires.
• In Malaysia, there was a two-to-threefold increase in
outpatient visits for respiratory diseases, as winds
carried plumes thousands of miles.
• In Indonesia, 40,000 were hospitalized and losses
in terms of property, agriculture and disrupted transport
were estimated to be US $9.3 billion (Arnold
2005).
• In Alta Floresta, Brazil, there was a twentyfold
increase in outpatient visits for respiratory diseases.
• In Florida, US, there was a 91% increase in emergency
visits for asthma, 132% increase in bronchitis
and 37% increase in chest pain.
– P.E.
THE FUTURE
CCF-I: ESCALATING IMPACTS
Continued warming favors more fungal and insect of
forests, and more harsh weather will further weaken
tree defenses against pests. Meanwhile, land-use
changes as a result of human activities and spreading
wildfires can disrupt communities of predators and prey
(for example, birds and leaf-eating caterpillars) that
have co-evolved and keep populations of pests in
check. The ecological implications for essential forest
habitat and forest functions (water supplies for consumption,
agriculture and energy; absorbing pollutants;
drawing down carbon; and producing oxygen) will
continue to deteriorate.
Figure 2.26 Rising CO 2
and Wildfires
Change
140%
120%
100%
80%
60%
40%
20%
0%
-20%
Acreage Burned
Escapes
Santa Clara Amador-El Dorado Humbolt
Firefighting Region
Chart shows results for contained wildfires (acres burned) as well as
catastrophic “escaped” fires (number of fires) under a double CO 2
scenario for three major climate and vegetation zones in California.
Some subregions exhibited up to a four fold increase in damages.
Results calculated by coupling climate models with California
Department of Forestry wildfire models, assuming full deployment of
existing suppression resources.
Source: Tom et al.1998
Northern California forestry services have coupled
California Department of Forestry wildfire models with
the Goddard Institute for Space Sciences general circulation
model of global climate (Torn et al. 1998; Fried et
al. 2004). The regions studied include substantial areas
of wildlands that interface with urban areas on the margins
of the San Francisco Bay area, the Sacramento metropolitan
area, and the redwood region's urban center
in Eureka. According to this analysis, climate change will
be associated with faster burning fires in most vegetation
types, resulting in more than a doubling of catastrophic
escaped fires under a doubled CO 2
environment. (see
figure 2.25). The results include full use of existing fire
suppression resources, but exclude the impacts of several
important factors, such as beetle infestations, increased
lightning activity (the primary cause of wildfire ignitions)
and shifts in post-fire plant regimes towards more flammable
vegetation types (typically grasses).
Empirical data combined with predictive modeling in
British Columbia, performed by the Canadian Forest
Service, demonstrate that climate change is eroding the
ecological barriers (non-forested prairies and the high
elevations of the Rocky Mountains) that once prevented
northward expansion of the mountain pine beetle.
Adjacent boreal forests in northern Alberta and
Saskatchewan, which are populated by susceptible
jack pine (Pinus banksiana, Lamb) may serve as the
next large-scale emergence zone of the beetle advance
(Furniss and Schenk 1969; Safranyik and Linton 1982;
Cerezke 1995; Carroll et al. 2003; Alberta
Sustainable Resource Development 2003).