Climate variability and freshwater – can we adapt?

Climate variability and freshwater – can we adapt?

David L. FeldmanSchool of Social Ecology

University of California, Irvine

National Taipei UniversityTaipei, Taiwan

December 20, 2012

Introduction

Adaptation –deliberate measures to enhance humankind’s ability to manage water supply, attenuate demand in face of climate uncertainty.

Different from prevention or mitigation. Requires imaginative management. Requires co-production of knowledge.

Why adapt? Regions experiencing periodic drought or flood are likely to see worse extremes in future.

Is climate change real?

It’s like asking “whether steroids helped a baseball player hit a home run in the bottom of the 9th inning of the World Series.”

If the player was able to hit home runs before taking steroids, it would be impossible to know whether any particular home run could be traced directly to performance-enhancing drugs.

However, at the end of the season, it would be clear that the player hit home runs more often.

“That’s what we have here . . . we’ve juiced the world's climate system by putting these gases in the atmosphere.”

Source: Anthony Leiserowitz, Yale Project on Climate Change, October 2012).

Climate change – projected impacts

Source: IPCC, 2007

Evidence of climate variability

Lake Mead (Colorado River, USA) water levels: 1935 - present

Elephant Butte Reservoir (Rio Grande, USA): 2000 - 2012

Polar Ice pack shrinkage: 1979 – 2008 (NRDC

Climate variability and Taiwan – one illustration

Source: Ts’ui-jung Liu, Institute of Taiwan History, Academia Sinica, October 2011

Some compelling challenges Changes in seasonal distribution and amount of precipitation – e.g., in S. Taiwan, intensity of future precipitation likely to increase, stream-flow and runoff will increase during rainy season, decline in dry season.*

Increase in precipitation intensity.

Change in balance between snow and rain.

Increased evapo-transpiration and reduction in soil moisture.

Changes in vegetation cover.

Accelerated melting of glacial ice.

Increase in fire risk.

Increased coastal inundation and wetland loss from sea level rise.

Effects of CO2 on plant physiology – reduced transpiration/greater water use efficiency.

Sources: Climate Institute, 2010 http://www.climate.org/topics/water.html * Pao-Shan Yu, et. al., J. of Hydrology, March 2002

Three venues for adaptation• Cities – water supply and flooding• River basins – drought, flooding, collaboration among users.• International activities – diffusing innovation.

Los Angeles– adaptation

• Since 1970s, has emphasized conservation – average daily demands same as 1980, despite 1.1 million more people (in county).

• Storm-water capture, wastewater reuse being actively explored.

• Climate change explicitly embraced in regional plans (i.e., Metropolitan Water District). Questions posed:

• How will climate change affect water rights acquired from regional agricultural users?• How might seismic events disrupt aqueducts & compound climate impacts?

Tokyo – adaptation

• Despite household conservation efforts, per capita consumption has increased steadily since 1980s.

• Explicit concern with climate variability influencing responses; e.g., • Wastewater reuse being introduced on large-scale• Storm-water harvesting for non-potable needs – gardens, parks.

• Restrictions on groundwater withdrawals.

Mexico City – adaptation

• One of world’s largest, fastest growing megacities, (>20 million)• Plans long underway to adapt to growing water demands now being adjusted for climate change

• Additional water transfers to recharge aquifers.• Reduce residential water demand – 20% reduction goal.• Greater use of reclaimed wastewater for local agriculture and non-potable uses.• Storm-water capture for groundwater recharge.

• Typhoons/rainstorms often occur in summer.• Mudflows & landslides arise in sloped areas of metro area.• Flooding a critical issue.• Strategies – improve agricultural drainage, upstream water and

soil conservation, improve urban drainage system

Taipei – flood adaptation

Source: Fei-Yu Kuo, Department of Urban and Housing Development, Council of Economic Planning & Development , Taiwan

Hadejia-Jama'are Basin

Hadejia-Jama’are Basin – adaptation challenges

Climate variability – recurrent problems.

Basin residents rely on subsistence farming, small scale fisheries.

In 1970s two major dams built to ensure irrigation supply, flood control – generated unanticipated “cascading” impacts:

Silt backed-up behind dams; water released earlier to dilute silt. Earlier releases led to downstream floods. Floods encouraged infestation of typha grass, clogging streams. Agriculture and local fisheries declined. Farmers compensated by digging small channels to reduce floods; led to more erosion,

lower agricultural productivity.

Empowerment, capacity-building, adaptation

2002 – World Conservation Union, UK partnered with Nigeria to “build local water resources management capacity” in basin – Joint Wetlands Livelihood project.

Goals: Improve use of local knowledge, introduce pilot projects, demonstrate best-management practices to restore economy & local ecology:

Coordinate projects among different levels of government, preserve existing floodplain income from farming, grazing, non-timber forest products, fishing.

Preserve wetlands to restore dry-season grazing, groundwater recharge, waterfowl habitat – during drought.

Provide local level forums comprised of farmers, women’s groups, others – engage in community-level training, apply local knowledge.

Watershed management “game” – farmers serve as students, role-play solutions to local problems –

Participatory innovations

Break-out discussions – comparing solutions and reaching accord – JWL Hadejia office, Dauchi, Nigeria.

Session 1 – users brainstorm methods to maintain income and production with less water.Session 2 – users prioritize methods by voting – results become basis for by-laws to be followed by farmers.Session 3 – users discuss how institutions should assist in conflict resolution, provide additional information, support agreements.Session 4 – users review, reflect, conduct evaluation and specify actions.

Bengali delta - Bangladesh

Coastal detail

Ganges delta

Delta challenges 160 million residents, by 2050, 220 million – chronic flooding from cyclones,

tropical storms has killed thousands.

Sea level rise worsens floods –may displace 15% of population.

Ganges, Brahmaputra Rivers constantly shift, making it difficult to secure banks, protect farmland.

In 1990s, World Bank project, backed by France, Japan, US, proposed 8,000 km of dikes to control rivers:

$10 billion proposal opposed by farmers whose land would be taken. Massive Dutch-style dikes to hold back sea, cyclone-induced waves, even less

practical, according to IPCC – local soils too unstable.

Empowered participation, locally-adaptive management

NGOs have developed local-scale, low-tech adaptation measures:

UK-based Practical Action – 2-foot-high concrete plinths topped with inexpensive jute panel walled homes –less likely to be washed away by tropical storms.

US-based CARE helps people along coast rediscover forgotten farming techniques such as Baira cultivation, floating gardens suited to areas subject to lengthy inundation.

Salt-tolerant varieties of rice introduced; some paddies converted to shrimp, crab ponds. Family planning efforts showing progress – fertility rates < 2/3 since 1977.

Illustrate how incorporating voices of those impacted by flood produces innovations more likely to be appropriately – and economically – scaled.

Flood adaptation innovations

Proposed agricultural mats – US architect Christopher Kouttron

Floating farm

“Stilt’ homes – Gazipara, Bangladesh