Past, Present, and Future Climate Change: Can Palaeoecology Help Manage a Warming World? - Biodiversity Conservation and Environmental Change - page 87

5
Past, Present, and Future Climate
Change: Can Palaeoecology Help
Manage a Warming World?
The Earth's climate has always varied, but the rate of climate change that is taking place now
is probably at least an order of magnitude higher than at any other time in the past 65 million
years (Diffenbaugh and Field 2013). Scenarios suggest that we are now approaching tempera-
ture increases beyond those of previous interglacials (Figure 5.1), and it is also the first time in
the Earth's history that one species has so much potential to influence the processes and
impacts of climate change. Human impact is of such magnitude that we have arguably cre-
ated a new geological epoch, the Anthropocene (Steffen et al. 2011, Zalasiewicz et al. 2011) and
it has been predicted that between 15 and 37% of species existing today may be 'committed to
extinction' by 2050 due to climate change (Thomas et al. 2004). All of humankind depends on
the biodiversity that underpins vital ecosystem services, like soil formation, water provision,
carbon storage and climate regulation (see Chapter 6), and urgent action is needed to miti-
gate, accommodate, and ameliorate the effects of climate change (Rockström et al. 2009, Bar-
nosky et al. 2012, Moritz and Agudo 2013). Enormous efforts are being made to predict the
magnitude, rate and effects of future warming, and the palaeoecological record is providing
vital clues regarding ecological resilience and the adaptive capacity of socio-ecological sys-
tems in changing environments (Moritz and Agudo 2013).
To conserve biodiversity in a changing climate, we need to understand how ecosystems
responded to past climate change, model the interactions between climate and vegetation,
and predict changes in biodiversity distribution and ecosystem function under future climate
change and land-use scenarios (Sutherland 2006, Brooke 2008, Pereira et al. 2010, Settele
et al. 2012, Spangenberg et al. 2012). Climate change-integrated conservation strategies
require collaboration between palaeoecologists, ecologists, ecophysiologists, biogeogra-
phers, climatologists, and modellers, so that ecosystem management and strategic conserva-
tion planning can adapt to environmental change (Hannah et al. 2002a, b, Dawson et al. 2011,
Hannah 2011, Thomas et al. 2011, Gillson et al. 2013). Dawson et al. (2011) developed an inte-
grated approach to climate change biodiversity assessment, which incorporates direct obser-
vations of changing species distributions and past distributional changes from the palaeo-
record, alongside an understanding of the physiology underlying these climatic tolerances,