Climate Change and Tourism - UNEP - Division of Technology ...

52 Climate Change and Tourism – Responding to Global Challenges
Box 3 Recommendations for impact assessment studies in tourism
Climate change impact assessments in many socio-economic sectors, including tourism, have
often employed a very limited range of climate change scenarios to explore the potential impacts
of climate change; sometimes using only one GCM or a single GHG emission scenario (e.g.,
IPCC A2 scenario or another SRES scenario). Such an approach does not adequately represent
the uncertainty in future climate conditions and produces an unrealistically narrow assessment
of the potential impacts and possible adaptation requirements. Climate change assessments,
in tourism, as in other sectors*, should better take into account of the uncertainty in climate
change scenarios. In any study, the minimum requirement is to be transparent about climate
change scenarios utilized, including the GHG emission scenarios and the climate models used.
As recommended by the IPCC, impact assessments should incorporate multi-GCM/RCM and
multi-emission scenario combinations to represent the full range of possible future climates for a
study area. Since developing several scenarios is costly and time-consuming, alternate strategies
are possible, such as presenting the whole range of scenarios for a limited number of critical
parameters and selecting a representative set of climatic scenarios for use in the impact analysis
(e.g., the warmest and driest scenario as well as the least warm and wettest scenario). This requires
a general improvement in the availability of user friendly climate change scenario data, which
has been an important barrier in some regions. To overcome this barrier, some countries, such as
Canada, have made all currently available GCM data available in a user friendly format for any
location. For example, see the Climate Change Scenario Network (http://www.ccsn.ca/).
8.3 Latest Results on Past and Future Climate Change *
8.3.1 The Changing Climate
The IPCC AR4 173, 174 summarized the growing evidence from multiple natural systems that indicate
that the global climate is changing. Eleven of the last twelve years rank among the 12 warmest years
in the record of global surface temperature since 1850 (Figure 8.4). The warming trend over the last 50
years (0.13° C per decade) is nearly twice that for the last 100 years (Figure 8.4). The total temperature
increase from 1850–1899 and 2001–2005 is 0.76° C. Widespread decreases in glaciers and ice caps
and warming ocean surface temperature have contributed to sea level rise. Global average sea level
rose at an average rate of 1.8 mm per year over 1961 to 2003, and at approximately 3.1 mm per year
from 1993 to 2003. The biological response of ecosystems and individual species has been recorded
on every continent. 175
* It is important to note that impact assessment studies in the tourism sector are not especially weaker than those conducted
in other sectors.
UNWTO, 9 July 2008