Assets exposed to sea-level rise in coastal cities by 2070
259
views
0
faves
0
shares
However, overall, all regions are expected to suffer significant net damage from unabated climate
change according to most estimates, but the most significant impacts are likely to be felt in developi...
ng
countries because of already challenging climatic conditions, the sectoral composition of their economy
and their more limited adaptive capacities. The costs of damages are expected to be much more important
in Africa and Southeast Asia than in OECD or Eastern European countries (see Nordhaus and Boyer, 2000;
Mendelsohn et al., 2006 and OECD, 2009a for a compilation of results). Coastal areas would be
particularly exposed as well (Box 3.3).
Recent research suggests that the impacts of unabated climate change may be even more dramatic
than estimated by the IPCC. The extent of sea-level rise could be even greater (Oppenheimer et al., 2007;
Rahmstorf, 2007). Accelerated loss of mass in the Greenland ice sheet, mountain glaciers and ice caps
could, according to the Arctic Monitoring Assessment Programme (AMAP, 2009), lead to an increase of
global sea levels in 2100 of 0.9m-1.6 m. In addition, researchers investigating climate feedbacks in more
detail have found that rising Arctic temperatures could lead to extra methane emissions from melting
permafrost (Shaefer et al., 2011). They also conclude that the climate sensitivity could be higher than
anticipated, meaning that a given temperature change could result from lower global emissions than those
suggested in the Fourth IPCC Assessment Report. Climate change might also lead to so-called “tipping-points”, i.e dramatic changes in the system that
could have catastrophic and irreversible outcomes for natural systems and society. A variety of tipping
points have been identified (EEA, 2010), such as a 1 °C-2 °C and 3 °C-5 °C temperature increase which
would respectively result in the melting of the West Antarctic Ice Sheet (WAIS) and the Greenland Ice
Sheet (GIS). The potential decrease of Atlantic overturning circulation9
Climate change impacts are closely linked to other environmental issues. For example, the
Environmental Outlook Baseline scenario projects negative impacts of climate change on biodiversity and
water resources. Without new policies, climate change would become the greatest driver of future
biodiversity loss (see Chapter 4 on biodiversity). The cost of biodiversity loss is particularly high in
developing countries, where ecosystems and natural resources account for a significant share of income.
Climate change can also affect human health; either directly through heat stress or indirectly through its
effects on water and food quality and on the geographical and seasonal ranges of vector-borne diseases
(see Chapter 6). Climate change will also have an impact on the availability of freshwater (see Chapter 5).
could have unknown but
potentially dangerous effects on the climate. Other examples of potential non-linear irreversible changes
include increases in ocean acidity which would affect marine biodiversity and fish stocks; accelerated
methane emissions from permafrost melting, and rapid climate-driven transitions from one ecosystem to
another. The level of scientific understanding – as well as the understanding of possible impacts of most of
these events – is low, and their economic implications are therefore difficult to estimate. Some transitions
are expected to occur over shorter timeframes than others – the shorter the timeframe, the less opportunity
to adapt (EEA, 2010).
Did you work on this visual? Claim credit!
Get a Quote