Transcript An Overview of Methods for Estimating Urban Populations

Mapping the Dollar value of natural
production and the Dollar cost of human
consumption globally
Costs …………......&……………Benefits
(Impervious Surface)
(Net Primary Productivity)
Paul C. Sutton & Benjamin Tuttle
Department of Geography
University of Denver
Denver, CO 80465
[email protected]
Approach and Assumptions
• The impact of Human Activity on the earth
can be mapped and monetized using
Impervious Surface Area as a proxy.
• The value of the world’s ecosystem services
can be mapped and monetized using Net
Primary Productivity as a proxy.
• Human Impact is Balanced with Ecosystem
Service at the Global Scale and valued at
roughly the global GDP of $50 Trillion.
Global
Estimates of
ISA have
been
developed
using simple
OLS models
derived
from DMSP
nighttime
imagery and
LandScan
Population
Density
These Models are applied Globally
Christopher Elvidge; Benjamin Tuttle; Paul C. Sutton; Kimberly E. Baugh; Ara T. Howard; Christina
Milesi; Budhendra Bhuduri, Ramakrishna Nemani (2007) Global Distribution and density of Constructed
Impervious Surfaces Sensors 2007, 7, pp 1962-1979
Our Preliminary work suggests Impervious Surface Area
is a reasonable proxy measure of Ecological Footprint
Impervious Surface Area per Person vs. ecological footprint per person for
149 countries using Ecological Footprint Data from Wackernagel et. Al.
Mapping the Dollar Value of
Ecosystem Services
• Valuation and mapping of ecosystem service is a
contested and challenging enterprise.
• We chose to use Net Primary Productivity (NPP) as a
proxy of ecosystem service value because it is an
interesting proxy of where solar energy conversion
takes place.
• Other measures based on land cover, biome, spatial
context etc. could also be explored.
Costanza, R; d’Arge, R; de Groot, R; Farber, S; Grasso, M; Hannon, B; Naeem, S;
Limburg, K; Paruelo, J; O’Neill, R; Raskin, R; Sutton, P; van den Belt, M; (1997) The
Value of the World’s Ecosystem Services and Natural Capital Nature Vol 387 May 15
Global Datasets of Net Primary Productivity
have been developed and explored
Imhoff, Marc L., Lahouari Bounoua, Taylor Ricketts, Colby Loucks, Robert Harriss, and
William T. Lawrence. 2004. Global patterns in human consumption of net primary
production. Nature, 429, 24 June 2004: 870-873.
This is hopefully a provocative exercise exploring ideas
of carrying capacity, I = P*A*T, Ecological Footprints,
Ecosystem Service Valuation, and
Sustainable Development
We simply allocate $50 Trillion of
‘COST’ via the Global Map of
Impervious Surface and allocate
$50 Trillion of ‘Benefit’ via the
Global Map of NPP. The
rationale for equivalence is an
assumption that we are at some
sort of ‘Carrying Capacity’. The
rationale for $50 Trillion is it is
roughly equivalent to the Global
Annual Gross Domestic Product.
Wackernagel, M. and Rees, W., 1996, Our
Ecological Footprint: Reducing Human
Impact on the Earth. New Society Publishers,
Gabriola Island, BC
Canada. 176 p. ISBN: 9780865713123.
Spatially Explicit Representation of
$ Value of NPP - $ Cost of Impervious Surface
Next few slides are national aggregations of $ NPP, $ ISA, & Difference
Aggregate National Map of Dollar Benefit of
Ecosystem Services using NPP proxy
Aggregate National Map of Dollar Cost
of Human impact using ISA proxy
Aggregate National Map of
$ Benefit of NPP - $ Cost of ISA
Sutton, Paul; (2003) An Empirical Environmental Sustainability Index derived solely from Nighttime
Satellite Imagery and Ecosystem Service Values 2003 Population and Environment 24(4)
Top 20 ‘Surplus’ Nations
The Top 20 ‘Debtor’ Nations
Discussion Questions?
• Does this make any sense?
• Is ISA a good spatially explicit choice for the ‘cost’
of human impact?
• Is NPP a good spatially explicit choice for the
‘benefits’ of ecosystem services?
• Is $50 Trillion a reasonable number to use?
• How big a sin is it to ignore the oceans?
• Is this a fair balance with respect to ongoing
population vs. consumption debates?
Conclusion
• Not much to say –
• The pictures and tables are the gist of it.
• This powepoint can be downloaded from:
• N:\ConferencePowerpoints\AAG
Presentations\BostonAAGsutton2008.ppt
• The Table can be downloaded from:
• N:\ConferencePowerpoints\AAG
Presentations\TheFinalISAvNPPtableAAG.xls