Factors that Increase Vulnerability

Physical• Rising temperatures, increasing evaporation, increase in precipitation received during extreme events, increase in length of dry spells • Excess groundwater pumping during drought results in high energy use

Social• High rates of population growth, migration, and rapid urbanization• Competition between urban and rural areas for water resources

Legal• Poor enforcement of water law (Mexico)• Perverse incentives in water law: “Use it or lose it” (U.S.)

Policy and Institutional• NAFTA-catalyzed border industrial and population growth

• Leads to increased water demand• Long-term planning hampered by:

• Short-term water management appointments • Alternancia – new governments, new priorities

• Poor regulation of wastewater use in agriculture

Economic• Poverty and uneven access to resources• Water is undervalued• Commercial agriculture exports huge quantities of “virtual water”

Institutions and Societal Impacts of Climatein the Arizona-Sonora Portion

of the U.S.-Mexico Border RegionRobert Varady1, Gregg Garfin1, Margaret Wilder1, Christopher Scott1, Anne Browning-Aiken1, Barbara Morehouse1, Nicolas Pineda5,

Ashley Coles1, Jamie McEvoy1, Kate Sammler1, Andrea Ray3, David Gochis4, Tereza Cavazos2, Luis Farfan2, Rolando Diaz1

1University of Arizona, 2Centro de Investigación Científica y de Educación Superior de Ensenada, 3NOAA Earth System Research Laboratory, 4National Center for Atmospheric Research, 5Colegio de Sonora

Aims

• Assess climate-related vulnerabilities and impacts in the region• Examine the nexus of climate, institutions, water policy, economic development, and land use practices• Engage in climate knowledge exchange with stakeholders to:

• Evaluate the salience and usability of existing climate products• Identify promising avenues for introducing climate science into

policymaking and management decisions• Formulate climate science research priorities and questions

1. Inefficient irrigation, high evaporative losses

5. Rapid expansion of coastal resorts and retirement communities

4. Rapid urban expansion, but inadequate water delivery, and limited water service (6-8 hr/day)

2. Rapid urban growth (above); into fire-prone and rural areas (left)

3. Leaky infrastructure and groundwater depletion to sustain export agriculture

6. Desalinating ocean water is seen as a desirable adaptation by many water managers

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Factors Exacerbating Risk

ArizonaSonora

Physical Context

Exposure to Climate Risk• Semiarid climate

• Precipitation: 100-500 mm/yr• 70% precipitation during summer

• High interannual precipitation variability• El Niño-Southern Oscillation

• Extreme weather• Summer thunderstorms• Tropical cyclones

• Prone to drought• e.g., 1950s, 1800s, 1750s, 1670s, 1560s• Increasing temperatures

Hydrology and Water Resources• Scant surface water resources, but…

• Prone to flooding• Bi-national streams and aquifers• Agriculture uses 70-85% of regional groundwater

• Groundwater overdraft and salt-water intrusion

Above: Areas of substantialgroundwater depletion

Weiss and Overpeck (2005) note increasing temperatures and a longerfrost-free season in the region

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AZ State Nogales Douglas

% of Population Living in Poverty

Recent Funding• Inter-American Institute for Global Change Research: “Information Flows and Policy: Use of Climate Diagnostics and Cyclone Prediction for Adaptive Water-Resources Management Under Climatic Uncertainty in Western North America” (http://udallcenter.arizona.edu/iai/index.php)• NOAA Sectoral Applications Research Program: “Moving Forward: Adaptation and Resilience to Climate Change, Drought, and Water Demand in the Urbanizing Southwestern United States and Northern Mexico”(http://udallcenter.arizona.edu/sarp/)

Project Contacts: • Robert Varady (rvarady@email.arizona.edu) • Margaret Wilder (mwilder@email.arizona.edu)• Chris Scott (cascott@email.arizona.edu)• Gregg Garfin (gmgarfin@email.arizona.edu)

Institutional Issues

Challenges• Poor binational federal relations, resulting in suspicions of motives• Limited use of science in planning and operations• Bureaucratic inertia• Poor information flows at the transboundary regional scale

• e.g., census, maps, economic and hydroclimatic data • Inadequate funding for resource management (Mexico)

Opportunities• Increased local water governance through Mexican watershed councils (consejos de cuenca)• Binational initiatives

• Transboundary Aquifer Assessment Program • Border Governors Conference Water Committee

• New emphasis on climate change• State Climate Action Plans (Mexico)• Capacity building through collaborations:

• Scientists, NGOs, and stakeholders• Border Climate Summary newsletter*

• Development of a culture of water conservation• Drought planning

*http://www.climas.arizona.edu/forecasts.html

IARU Conference, March 2009