Grantee Research Project Results
1995 Progress Report: Vulnerability of Low-Income Households to the Hydrologic Effects of Climate Change
EPA Grant Number: R824805Title: Vulnerability of Low-Income Households to the Hydrologic Effects of Climate Change
Investigators: Wernstedt, Kris , Austin, David , Hersh, Robert
Institution: Resources for the Future
EPA Project Officer: Chung, Serena
Project Period: October 1, 1995 through September 1, 1998
Project Period Covered by this Report: October 1, 1995 through September 1, 1996
Project Amount: $440,000
RFA: Regional Hydrologic Vulnerability to Global Climate Change (1995) RFA Text | Recipients Lists
Research Category: Climate Change , Water , Ecological Indicators/Assessment/Restoration
Objective:
The potentially disproportionate share of global climate change impacts that disadvantaged groups in particular areas may experience is an important question for decision makers concerned with the risks of climate change, both from the standpoint of evaluating the fairness of possible responses as well as from a pragmatic perspective of gauging the likely support for policy options. This study tackles this question by examining three dimensions of vulnerability of low-income households to climate variation in the Willamette River basin in Oregon. In the exposure dimension, we use a mass balance water management model of the Willamette watershed to simulate a range of possible reallocations of freshwater resources that might follow from climate change. In the resilience dimension, we econometrically estimate income and employment response to variations in precipitation and temperature over the last quarter-century in the basin. We distribute the responses with a matrix of household income group and sector-specific income flows that we have constructed from published secondary data. In the capacity dimension, we examine the processes by which water management institutions in the area, principally drinking water utilities, serve low-income households. Throughout our analysis, we rely on a geographic information system (GIS) to correlate indicators of coping capacity with other dimensions of vulnerability and with socio-economic characteristics in the watershed. The GIS also is central for disaggregating data for use in our econometric estimations.
Although it is by no means certain that climate change will generate significant social and economic effects, the results of the study should prove useful for federal policy makers concerned with possible responses to climate change, as well as those with environmental justice responsibilities. The work also may help state and local agencies, two groups that likely will become the primary players in coping with the effects of climate change, a preview of the kinds of issues that they will be forced to address if the potential effects of climate change materialize.
Progress Summary:
Chief accomplishments over the last twelve months have been the estimation of coefficients for the synthetic climate record simulations; development of a multi-regional regional watershed runoff model; construction of the income allocation matrix; and design, pretesting, and partial completion of the water utility survey. These efforts, together with the construction of the GIS and the economic databases last year, constitute nearly all of the data collection/processing component of our study, the most significant (in terms of time and budget) part of the project.
With respect to the synthetic climate record, we have run over 25,000 independent regressions on four climate variables (independent variables are various combinations of latitude, distance from ocean, elevation, and year characteristics) for approximately 125 climate stations in the watershed. Each regression is for a single month in the calendar year and includes between 25 and 95 years of data, depending on the variable and station. Parameter estimates from these regressions will be used as described below.
In the watershed runoff model, we have developed an algorithm that uses Thornthwaite water budget calculations. This allows the simulation of runoff in each of ten subwatersheds in the Willamette basin as a function of precipitation, temperature, soil type, and vegetative cover. In a preliminary analysis earlier this year with limited data, we obtained acceptable fits between predicted and adjusted observed values. We expect to improve the fit and finish the runoff simulation by using a longer calibration period once we establish the full synthetic climate record in the next 6 months.
We also have neared closure on the income allocation matrix. This matrix, as described above, traces the flows within the basin from each economic sector to each income group. The major component of this matrix contains salary and wage income, constructed principally from occupational employment survey data collected in Oregon and U.S. Bureau of the Census data on household and family income distribution.
And finally, we developed our survey instrument for querying water utility managers and administered the survey to about one-quarter of the forty-five water utilities in the Willamette basin that we are surveying. Our objectives with this survey are to find out how the utilities have responded to floods and droughts during the past decade, how susceptible their systems remain to extreme events, and the extent to which the utilities have implemented measures to buffer low income households from disruptions to the water system.
Future Activities:
In the final year of the project, we will pull together the various threads outlined above. More specifically, we will use the parameter estimates from the climate variable regressions to construct a synthetic climate record at a grid of points throughout the watershed. We will use these gridded points, in turn, as climate variables in our econometric estimations as well as in the Thornthwaite water budget runoff calibrations. Once the econometric and Thornthwaite models are estimated, we will use projections from an independent regional climate modeling exercise currently underway to simulate economic and runoff responses under altered climate scenarios. The economic responses will be distributed to income groups via the income allocation matrix, while the runoff simulations will be used in our examination of which water utilities might be stressed by the hydrologic variability. In the final stage of our project, we also will finish our GIS overlays of socioeconomic characteristics on flood and drought proneness.Journal Articles:
No journal articles submitted with this report: View all 6 publications for this projectSupplemental Keywords:
socio-economic, hydrology, water utilities, equity, Columbia River Basin., RFA, Scientific Discipline, Air, Geographic Area, Water, Hydrology, Water & Watershed, climate change, State, Atmospheric Sciences, Ecological Risk Assessment, EPA Region, Social Science, Watersheds, water resources, environmental monitoring, policy making, Oregon, economic models, hydrologic models, socioeconomic indicators, climate models, human dimension, low income households, land and water resources, Region 10, climate variability, climatic modelsProgress and Final Reports:
Original AbstractThe perspectives, information and conclusions conveyed in research project abstracts, progress reports, final reports, journal abstracts and journal publications convey the viewpoints of the principal investigator and may not represent the views and policies of ORD and EPA. Conclusions drawn by the principal investigators have not been reviewed by the Agency.