1. Water and Climate

2. OUTLINE Factors affecting climate Projecting future climate scenarios
Climate change and water supplies
Management of impacts of climate change

3. Interannual variation of rainfall in Meghalaya

4. Interannual variation of rainfall in Meghalaya

6. What causes climate: Solar energy heats
different continents and Oceans
to different extents
This creates pressure differences
Which lead to wind and ocean
Currents
These currents strongly influence
Precipitation and temperature

7. Another factor that affects climate: Greenhouse gases that act as a blanket

8. Wind currents
Example:
India monsoon

9. Ocean currents: Warm & cold Skeleton coast, Namibia Pacific Coast,
Peru

13. A warming world…
Glaciers on Mount Kilimanjaro have lost 85 percent of their coverage since 1912
The Quelccaya ice cap in southern Peru – the largest tropical ice field on Earth, has retreated 25 percent since 1978
Ice fields in the Himalayas that have long shown traces of the radioactive bomb tests in the 1950s and 1960s have since lost that signal as surface melting has removed the upper layers and thereby reduced the thickness of these glaciers
All of the glaciers in Alaska’s vast Brooks Range are retreating, as are 98 percent of those in southeastern Alaska.  And 99 percent of glaciers in the Alps, 100 percent of those in Peru and 92 percent in the Andes of Chile are likewise retreating
Sea levels are rising and the loss of ice coverage in the North Polar region continues to increase annually.

14. What is the IPCC? IPCC = Intergovernmental Panel on Climate Change
Established in 1988 by the World Meteorological Organization and the United Nations Environment Programme
Objective: produce an assessment of the potential impacts of human-induced climate change and ways to adapt to and mitigate these impacts

15. IPCC Fourth Assessment Report (2007):
Global mean surface temperatures have increased 0.74ºC (±0.18) over the past 100 years
Warming rates are accelerating:
11/12 warmest years since 1850 occurred between
Changes in precipitation: amount, intensity, frequency, and type
General declines in the tropics; general increase in temperate and northern latitudes
Extreme hydrologic events appear to be becoming more frequent
Droughts, hurricanes, floods
Even where total precipitation has decreased, number of intense events show an increase
Ref: Cooley, 2009

16. Projecting future climate scenarios
General Circulation Models (GCMs) used to understand potential impacts of various greenhouse gas (GHG) emission scenarios on future climate conditions
Tested with simulations of features of recent climate and historical climate record
Climate change depends on future GHG emissions, which are uncertain, influenced by socioeconomic, demographic, and technological factors
Special Report on Emissions Scenarios (SRES)
Outlines 4 ‘storylines’ that include many different ‘scenarios’
Ref: Cooley, 2009

17. Storylines and scenarios of climate change
A1: ‘A future world of very rapid economic growth
Global population peaks in mid century
Rapid introduction of more efficient technologies
Convergence among regions
Capacity building
Reduction of regional differences in per capita income
A1 storyline is differentiated according to energy sources (fossil intensive vs. non-fossil fuel intensive)
HIGH greenhouse gas emissions
Ref: Cooley, 2009

18. Storylines and scenarios of climate change
A2: ‘self-reliance and preserved identities’; population growth increase but slow economic and technological growth
B1: population growth increase; change towards a service and information economy; reduction in material intensity and introduction of clean and efficient technology
LOWER greenhouse gas emissions because of emphasis on sustainability
B2: continuously increasing global population; intermediate economic development; less rapid technological change
Ref: Cooley, 2009

19. 16 GCMs on rainfall prediction for Tanzania

20. Precipitation projection for Wami Basin, Tanzania at a 50 km grid scale resolution

21. Changing climate conditions will affect water resources
While predicting climate is fiendishly complex…
Changing climate conditions will affect water resources

22. Surface water
Alterations in the amount and timing of flows would affect water supply
Snow-dominated basins will experience earlier peak flows, greater winter flows, lower summer flows
Rain-dominated basins will be most influenced by changing precipitation patterns, with predictions of greater winter flows and lower summer flows

23. Groundwater Impacts less well understood
Climate change could affect recharge rates and supply
Evaporation rates could affect quality of groundwater
Demand for groundwater could increase as surface water supplies change

24. Hydrologic extremes Climate change = greater climate variability
Higher risk of hydrologic extremes
Droughts - more frequent, more intense, longer lasting
Floods - shift in frequency, more intense

25. Water quality Expected increase in temperature in lentic systems
Lower oxygen
Moe algal and bacterial blooms
Intense rainfall events could wash more contaminants into water bodies
Increased salt water intrusion from rising sea levels

26. Water demand Remains to be studied in more detail
Certain sectors may be more sensitive to climate change
Agriculture - irrigation water
Urban areas of the US - lawn care water use
Industry - need for more cooling water requirements

27. Changing climate conditions will require water resource management interventions

28. Palmer et al. 2008: Likely to require management intervention:
300,000 km2 of basins with no dams
10 million km2 of dam-impacted basins
7% of world’s area; 1 billion people live in that area
Certain to require management intervention:
700,000 km2 of basins with no dams
5 million km2 of dam-impacted basins
4.2% of world’s area; 365 million people in that area

29. Climate change assessments must be interdisciplinary

30. Climate change assessments: “Vulnerability and Adaptation”
Vulnerability: a function of the magnitude of impacts of CC and sensitivity to the impacts
Developing countries are considered more vulnerable to climate change?
Stationarity: systems designed and operated based on historical climate conditions
Adaptation: initiatives to reduce vulnerability of natural and human systems to CC
Proactive vs. reactive management (No Regrets)
Structural vs. non-structural
Supply-side vs. demand-side

32. Adaptation assessment: practice of identifying options to adapt to CC
Consider availability, benefits, costs, effectiveness, efficiency, feasibility of options
Approaches:
Down-scaled GCMs and scenarios - mathematical relationships
Hypothetical modifications of temperature and precipitation (e.g., 10% increase)
Regional models then used to simulate future water conditions under altered climates

33. Ref: Gleick, 2009; Cooley, 2009

34. Adaptation Policy Framework (UN Development Programme approach)
Evaluation of vulnerabilities to current climate variability and extremes
May be more qualitative, used in data-limited areas
National Adaptation Programs of Action
Least developed countries
Address urgent needs related to CC
Build adaptive capacity, formation of expert groups
May not be adequate for addressing impacts of CC over long-term

35. CC Adaptation: Other considerations
Stakeholder participation
Economic costs of adaptation measures
UNFCCC - estimates adaptations for meeting water demand in 2030 associated with CC and socioeconomic trends: $ billion USD
Equity and ethical concerns
Who pays for adaptation measures?
Ref: UNFCCC 2007; Cooley, 2009

36. Watershed Restoration – enhance local water storage