An Empirical Environmental Sustainability An Empirical Environmental Sustainability Index derived solely from Nighttime Satellite Index derived solely from Nighttime Satellite

Imagery and Ecosystem Service ValuationImagery and Ecosystem Service Valuation

Paul SuttonPaul Sutton

psutton@du.edupsutton@du.edu

Department of GeographyDepartment of Geography

University of DenverUniversity of Denver

Outline“What is an Environmental Sustainability Index?”

• Data and Methods used to prepare this index• Results: Maps of Environmental Sustainability?• Other ESIs: Wackernagel’s Eco-Deficit & 2001 ESI• How do these ESIs intercompare?• Future Research directions

Sustainable Development & Environmental Sustainability

The 1987 Brundtland Report made the idea of Sustainability famous with the term ‘Sustainable Development’:

“Development that meets the needs of the present generation without compromising the ability of the

future generations to meet their own needs.”

Measuring Environmental Sustainability is a piece of this puzzle. Defining and/or measuring Environmental Sustainability is subject to great debate. Some methods have been suggested by the likes of Wackernagel, Ehrlich, and others.

Holdren & Ehrlich’s I=P*A*Tconception of environmental sustainability• Human ‘Impact’ must be balanced by the

Environment’s ability to absorb said impact

• Daily & Ehrlich suggest that ‘Impact’ should not exceed either ‘Maximum Sustainable Use’ (MSU) or ‘Maximum Sustainable Abuse’ (MSA)

• Absolute measures of ‘sustainability’ are virtually impossible to make; however, RELATIVE measures might be reasonably made in order to compare the environmental sustainability of nations or regions of the world

Measuring Human ‘Impact’• What data can be used in the I = P*A*T formulation?• If you use Population for P, GDP/Capita for Affluence,

and CO2 Emissions/GDP for Technology, then ‘Impact’ simplifies to total CO2 emissions

• Daily & Ehrlich used Energy Consumption per Capita to capture the A*T

• “Impact” is a function of both population size and individual consumption levels

• Nighttime Imagery from the DMSP OLS correlates with Population, Energy Consumption, CO2 emissions, and GDP and may be the best spatially explicit, single variable, measure of ‘Impact’

Measuring Maximum Sustainable Use and Maximum Sustainable Abuse

• The myriad ways in which human’s can impact the environment and the various ways the environment either supports or absorbs such actions are beyond the scope of this index.

• The proxy measure of MSA and MSU chosen was simply the value of the land’s ecosystem services as outlined by Costanza et. al. and calculated using a USGS global land cover data set at 1 km2 resolution

Deriving The Eco-Value / Night Light Energy Environmental Sustainability Index

This index is similar to the inverse of population density e.g. ‘square kilometers of land per person’

However; ‘square kilometers of land’ is adjusted by the land’s ecosystem service value; and, ‘per person’ is measured by the nighttime satellite imagery provided by the DMSP OLS

N a tio n a l In d e xVa lu e

Va lu e o f g iv en N ation ’s E co sy stem S erv ice s as es tim atedb y C o stan za a n d m ea su red b y

U S G S 1 k m 2 G lob al L an d C ov er G r id

A m ou n t o f L igh t E n ergy seen in N ig h ttim e S a te llite Im ag ery fro m

D efen se M eteo ro lo g ica l S a te llite P ro gram ’sO p eratio n a l L in escan S ystem (D M S P O L S )

A representation of the datasets used to calculate Eco-Value and Impact from around Central America

G lo b a l 1 k m I G B P L a n d -C o v e r D a ta se t 2 D M S P -O L S ‘E a r th a t N ig h t’ d a ta s e t

G u atem ala

E l S a lva d or

H on d u ra s

N icara gu a

C os ta R ica

E v e rg r ee n N ee d le lea f F o re stE v e rg r ee n B ro a d lea f F o res tD ec id u o u s N e e d le le a f F o r es tD ec id u o u s B ro a d le a f F o re stO p en S h r u b la n d sC los e d S h r u b la n d sW o o d y S a v a n n a sG ra s s la n d sP e rm a n e n t W etl an d sC ro p la n d sU rb a nC ro p la n d / N a tu r a l Ve g et a t ion W a te r

C o u n t r y P o p u l a t i o n ( 1 9 9 6 ) E c o - V a l u e / N i g h t L i g h t L o c a l R a n kB e l i z e 2 2 4 , 0 0 0 2 6 1 , 3 0 6 6

N i c a r a g u a 4 , 3 5 1 , 0 0 0 1 8 4 , 3 0 8 5H o n d u r a s 5 , 7 5 1 , 0 0 0 9 7 , 0 9 3 4G u a t e m a l a 1 1 , 2 4 1 , 0 0 0 6 2 , 0 8 5 3C o s t a R i c a 3 , 4 6 6 , 0 0 0 2 4 , 9 5 9 2E l S a l v a d o r 5 , 9 3 5 , 0 0 0 9 , 8 9 6 1

Sustainability Scores According to the Eco-Value / Night Light Energy Index

C o lo r C o d e to S u s ta in a b ility a c c o r d in g to E c o -Va lu e / N ig h t L ig h t E S I

Ve r y H ig h

H ig h L o wVe r yL o w

Av e r a g eJ u s t A b o v e A v e r a g e

Other National Measures of Environmental Sustainability

• The 2001 Environmental Sustainability Index produced by the Global Leaders of Tomorrow Environment Task Force of the World Economic Forum, The Yale Center for Environmental Law and Policy (YCELP), and the Center for

International Earth Science Information Network (CIESIN)

• The ‘Eco-Deficit’ derived by Wackernagel and Rees which results from their ‘Ecological Footprint’ analysis and is in essence the difference between ‘Available Ecological Capacity’ and the ‘Ecological Footprint’ of nations.

Ecological Footprint Analysis• “Ecological Footprint analysis is an accounting tool that

enables us to estimate the resource consumption and waste assimilation requirements of a defined human population or economy in terms of corresponding productive land area.”

• The ‘Ecological Footprint’ ESI is also a composite index involving many variables. However, in contrast to the 2001 ESI these variables focus on the nature and productivity of land resources, variability of human consumption patterns, and the energy accounting of each nation’s international trade.

The 2001 Environmental Sustainability Index• The 2001 ESI attempts to develop a ‘transparent,

interactive process that draws on rigorous statistical, environmental, and analytic expertise to quantify environmental sustainability’.

• Key Results are: 1) Environmental Sustainability can be measured, 2) The Index creates benchmarks of environmental conditions that can influence decision making, 3) Serious ‘data gaps’ for many nations of the world should be filled, 4) Economic conditions affect, but do not determine, environmental conditions; and, policy regarding these conditions are separate choices.

• Calculated for 122 nations using 5 ‘Core’ indicators each of which were derived from 67 other variables.

• Correlates Strongly with GDP per Capita

Comparing the 2001 ESI to the Eco-Deficit

• The Correlation between the 2001 ESI and the Eco-Deficit of Wackernagel is not significant (R2 = 0.03)

• The 2001 ESI incorporates more cultural and Institutional elements of sustainability along the lines of those described by Courtland Smith in a critique of the I=P*A*T formulation. And is consequently more of a ‘quality of life’ index than a sustainability index.

• The Eco-Deficit takes into account the separation of production and consumption in ways not accounted for in the 2001 ESI and may be a better of the global sustainability of a local people, nation, etc.

Scatterplots with

Regressions of the three

ESIs discussed

here

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ET

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SF

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SPJA

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GMFR

NL

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R a n k o f E c o -D e f ic it

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ht R = 0 .592

N ot Statistica lly S ign ificant N ot Statistica lly S ign ificant

Statis tically S ign ificant K e y fo r la b e lin g o f N a tio n s in S c a tte rp lo ts

N o te # 1 : R re p o r ted a re d e r iv e d fro m r a n k ed o r n o n -p a ra m e tr ic re g re s s io n

2

N o te # 2 : H ig h e r ra n k s in a l l c a s es s u g g e s t h ig h e r s u s ta in a b ili ty

High GDP/Capita Fips Medium GDP/Capita Fips Low GDP/Capita FipsCountries Code Countries Code Countries Code

GDP/Cap >$20,000 $20K>GDP/Cap >$3K GDP/Cap<$3,000

Austra lia AS Argentina AR Bangladesh BGAustria AU Brazil BR Ch ina CHBelgium BE Chile CI Co lomb ia COCanada CA Czech Republic EZ Costa R ica CSDenmark DA Greece GR Egyp t EGF inland F I Hungary HU Eth iopia ETFrance FR Ireland E I India INGermany GM Israe l IS Indonesia IDJapan JA Ma laysia MY Jordan JO

Ne ther lands NL Mexico MX Nige ria NINorway NO New Zea land NZ Pakistan PK

S ingapore SN Po rtuga l PO Pe ru PESweden SW Sou th A frica SF Ph ill ipines RP

Switze rland SZ Spain SP Poland PLUnited K ingdom UK Venezuela VE South Ko rea KSUn ited S ta tes US Tha iland TH

Turkey TU

Problems & Future Research General

• Definitions: lack of correlation between 2001 ESI and Eco-Deficit Index suggests that basic work on defining environmental sustainability still needs to be done.

• ESIs may be interesting but are they of any use?

Specific to Eco-Value / Night Light Energy Index

• Scale problems with measuring Eco-Value

• Spatial Context problems with measuring Eco-Value e.g. Flood control around resevoirs

Conclusions• Eco-Value / Night Light Energy Index correlates

strongly with Eco-Deficit but not at all with 2001 ESI

• Consilience as to what is meant by the term ‘Environmental Sustainability’ remains elusive

• The ‘Eco-Value’ / Night Light Energy Index is simple, relatively objective, measureable at fine spatial resolution, and updateable on a relatively frequent basis