Nordic Geographers MeetingRoskilde, Friday 27. May 2011Geography's potential contribution to Earth System Science Faculty of Science University of Copenhagen Morten Pejrup EAST
Definition of Earth System Science: The study of the Earth as a single, integrated biophysical and social system
The Earth System can be described as existing of a number of interacting ‘spheres’: • The hydrosphere • The cryosphere • The biosphere • The atmosphere • The lithosphere • The anthroposphere
Why establish an Earth System Science centre ? Because cutting edge research that potentially contribute to solving important challenges for the scientific community and society increasingly takes place at the interface between traditional research areas.
The overall aim of the EAST centre is to understand the properties and behaviour of the complex Earth System by empirical studies of the functioning, interaction and feed back effects of a large number of physical, chemical, biological and anthropogenic processes in the different spheres.
Today the most important single factor in changing the Earth and its surface is human action and exploitation of natural resources Some examples of the human foodprint on the Earth surface are:
Construction of advanced infrastructure like roads, railways and bridges
Mining and waste dumps in Canada. An extremly fast geomorphological process
Terrasing in south America causing severe soil erosion
Hotel in Virginia USA creates the need for coastal protection Hotel in Virginia USA creating the need for coastal protection
Deforestation and forest degradationState of the World's Forests World Resource Institute
There are two – logically incompatible – ways of defining Geography as a scientific discipline:
One, termed ‘chorology’, in which Geography is seen as the study of spatial distributions of phenomena at the Earth’s surface.
Another in which Geography is seen as the study of human-environment interrelationships, as ‘human ecology’ or, more recently, as the study of ‘socio-ecological’ systems.
The two definitions are ‘orthogonal’, and the two Geographies resulting from these definitions will logically include and exclude different sets of research activities. However in our daily praxis, geographers seldom reflect over this, and anyway many of our activities may fall under either of these definitions.
But surely research carried out using either of these definitions should be an important and integral part of: The study of the Earth as a single, integrated biophysical and social system !
Where does Geography play a leading role in Earth System Science? On the web sites of several ESSC. But in fact it is difficult to find such centres where geography is an important and integral part of the centre.
An example of an Earth System Science research question. Sea level rise: An important scientific and societal challenge.
Sea-level rise during the last 8000 years: 3.2 mm/y (North Sea) (Streif 2004)
There is a huge geographical variation in sea-level change Global changes in RSL during the Holocene period Source:Bird 1993 RSL change zoner, Bird
Mittivakkat Gletscher 1933. 1958 Sermilik station Ammassalik Greenland 2007
Sea level rise estimates by source and processes Hoffman et al. 1985
Changes of atmospheric CO2 concentrations and global temperature happens very fast
Causing increase in ocean surface temperature. Since 1870 there are large regional differences Source: European Environment Agency
Sea level change during the last decades and in the future
What is new concerning sea level change ? The new situation concerning sea level rise is not the size of the change but the rate of this change
Sea-level change during the last 40 mio. years (Archer, D, 2006)
1993-2003 Source: CEOS Climate Diagnostics
Regional differences in sea level rise ( IPCC) Variation in sea level 1955 – 2003 Measured from satelite This change pattern impacts different countries and societies quite differently. So an impact study is a truly geographical study. Thermal expansion computed
IPCC scenarios • Based on anticipated • Demography • Socio-economy • Technology • Human behaviour Source: Oldfield 2005
IPCC´s projections for sea level rise based on different scenarios
Modelling cascade of uncertainties when doing numerical modelling of how emission scenarios impacts the physical environment But what about scenario uncertainties caused by unpredicted human behaviour ?
The hard science approach of system description C-fluxe og -reservoirer Change since approx. 1800 Figur 8.3
Anthropocene era Characterized by human manipulation of the natural environment primarily the exploitation of natural resources
Anthropocene Stage 1 (1800-1945) • Evidence –increase in GHG concentrations, widespread • deforestration of temperate forests, etc. • Industrial Revolution - steam engine, fossil fuel energy • systems, rapid and wide spread of these energy systems • Flow-on effects - more efficient techniques for land clearing; • synthetic fertiliser; more reliable water supply and better • sanitation, leading to better public health. These • developments, in turn, led to an increase in population • AND their ability to consume. Steffen 2009
Anthropocene Stage 2 (1945 - 2010) The changing ’human enterprise’, from 1750 to 2000. Note the start of the ’Great Acceleration’ around 1950, when many activities began or accelerated sharply. From Steffen et al. 2004
Responses of the biophysical Earth System to the accelerating ’human enterprise’. The biophysical responses of the Earth System show many of the same features as the Great Acceleration in the human enterprise. From: Steffen et al. 2004
We have an unbalanced Earth system since humans started the Anthropocene era Therefore geographical and social sciences should play a much more visible role in Earth System Science side by side with the more hard core science branches
Examples of fields where Geography has a potential to contribute to Earth System Science Land use and land cover change including forest change. Interaction between climate change and food. production/consumption. Physical planning to reduce GHG emissions. Sustainable use of natural resources. Consequences of food waste. Migration patterns local and regional as a consequence of climatic and sea-level changes. Adaptation to climate change, not the least in developing countries. Adaptation – mitigation to climate change e.g. social barriers Etc ……….