WORKING GROUP SUMMARIES

CLIMATE WORKING GROUP

Compiled by Gregg Garfin, Climate Assessment for the Southwest, University of Arizona

The Climate Working Group (CWG) examined issues with regard to key research, monitoring, prediction, and communication needs for the Southwest with a special focus on Arizona. Among the issues considered most important for further research and attention, was the need to investigate the mechanisms that initiate and end drought – especially persistent severe drought. The CWG recommends special attention be given to decade-scale climate variations, usually the result of long-term ocean circulation patterns. Such variations are key to understanding the timescales associated with water supply replenishment, recovery from drought, and our ability to predict sustained drought.

The CWG recommends attention and resources be devoted to monitoring drought on many spatial and temporal scales, with a special emphasis on hydrological monitoring and improving the network of high-elevation monitoring sites. In addition, the CWG recommends support of global monitoring systems, in order to improve our ability to track the persistent ocean circulation patterns that control long-term drought in the Southwest, according to the most up-to-date research available.

The CWG found that our ability to predict drought is, at present, poor. Prediction is, in part, constrained by seasonal climate variations that limit forecast accuracy in spring, for example. However, the CWG is sanguine that drought forecasts will improve as deep ocean monitoring networks are expanded, and as information about decade-scale climate variations is incorporated into forecasts. In the absence of substantial forecast skill, and in addition to the present array of available forecast tools, the CWG recommends the development of scenario tests, based on analogues from historical and paleo-climate records.

Finally, the CWG suggests increased and improved communication, a single state drought spokesperson/coordinator, for example, the State Climatologist, and improved public education on drought in order to enhance our ability to mitigate the effects of, and respond to, persistent drought in the Southwest.

Key Issues

1) What starts and ends droughts?

Ø Drought inducing ocean patterns

Ø Persistence in climate system

Ø Long-term decade-scale climate variations

2) What could trigger a wet period?

Ø Some combination of the following, which affect the position of the Jet Stream and delivery of moisture to the Southwest:

§ Positive phase of the Pacific Decadal Oscillation (PDO), Negative phase of the Atlantic Multidecadal Oscillation (AMO: an example would be cooling in the North Atlantic Ocean), El Niño

Ø A consistent combination of positive PDO and negative AMO for ~3 years

Ø Individual events such as El Niño are merely interruptions

3) What drought indices are appropriate for AZ?

Ø Palmer Drought Indices (PDSI< PHDI), Standard Precipitation Index (SPI), Surface Water Supply Index (SWSI), Remote Sensing-derived indices

Ø For effective drought monitoring and assessment, there is a need to calculate drought indices at finer spatial scales

§ For example, is a county or watershed scale more appropriate?

4) What are the sub-regional spatial patterns of precipitation?

5) There is a need for research on droughtas well as drought monitoring to continue during wet periods.

Predictions

· No predictions were offered by the working group due the limitations of forecasting, however there are some recommendations for ascertaining possible predictions in the future:

Ø A more accurate 9-month forecast of ENSO-related sea surface temperatures is possible following the spring months. During the spring the ocean-atmosphere system is unstable, resulting in poor forecast skill. Forecasts can be provided by NOAA’s Climate Prediction Center (CPC), and from independent Global Circulation Models (GCM’s)

Ø With improved ocean monitoring more accurate forecasts are possible

Ø One long-term consensus forecast is possible

Scenario Testing vs. Prediction

· A distinction important to decision makers in the Southwest is that long-term drought is subject to irregular regimes, rather than regular cycles.

· Droughts recorded in the historical and paleo-climate records can be used to develop a variety of scenarios for planning.

· Decadal-scale climate information, such as that derived from records of the PDO, El Niño-Southern Oscillation (ENSO), and AMO, should be incorporated into scenario development and testing.

· It is important that researchers provide explicit confidence statements with regard to scenarios and scenario testing.

Possible Scenarios

· Re-evaluate management decisions from recent drought years.

Ø For example, if we had 100% foresight about 1999-2002 drought, could certain management decisions have mitigated the effects of drought?

· Mega-drought Scenarios – what would happen if the Great Drought (1200-1300’s) occurred today?

· What are the implications of Arizona-only droughts versus more regionally extensive droughts?

Research Needs

· Assess and Implement Solutions to State/Regional Monitoring Gaps

Ø Arizona requires soil moisture monitoring network of at least 25-30 stations

Ø Maintain funding for stream gauges, groundwater monitoring, and climate stations; high elevation precipitation/snow monitoring stations

Ø Update key tree-ring records

§ Need 2002 to establish a more effective baseline for State/Regional

§ Monitoring gaps

Ø Incorporate remotely sensed data in order to fill in spatial gaps, especially with regard to summer PPT

· Global Monitoring is necessary to help assess the status of climate patterns that affect the Southwest.

Ø Non-tropical deep ocean monitoring

Ø Support NOAA (CLIVAR) - have plans to increase instrumentation

Ø Be ware that better monitoring and forecast tools may be available in the near future

Ø Our understanding of climate is improving

Outreach & Communication Needs

· Improve public understanding through outreach programs.

Ø Make published research available to managers and decision makers; encourage & improve such efforts

· Have a state drought spokesperson.

Ø For example, a state climatologist

· Get the attention of federal forecast/climate agencies to focus on SW issues.

Ø For example, decadal-scale drought

· Increase communication among and between disciplines .

Ø For example, climatologists and economists

WATER WORKING GROUP

Compiled by Margot Truini¹, Abe Springer², David Ostergren³

¹USGS, Flagstaff Field Office, ²Northern Arizona University, Department of Geology, ³ Northern Arizona University, Center for Environmental Science and Education

Although the focus on droughts is usually on a lack of precipitation, this decrease in precipitation has consequences for hydrologic systems on and below the surface of the Earth. Drought leads to a decrease in recharge to aquifers through reductions in: (1) aerially distributed recharge, (2) focused recharge, (3) waste water return flows, (4) irrigation return flow, and from (5) increased evaporation and transpiration. The typical response of humans to a hydrologic drought is to: (1) pump more groundwater at existing wells to make up for loss of surface water, (2) drill more boreholes to augment supply, (3) remove riparian vegetation to decrease transpiration, (4) implement conservation practices, and/or (5) develop alternative water supplies.

Hydrologic drought impacts soil water and groundwater in many ways. It leads to a loss of groundwater and soil-water storage. This causes water levels in wells to be lowered and an increased depth to water in riparian areas with less water available for the plants to transpire. It also leads to a decrease in aquifer discharge. This will cause a decrease in base-flow in streams and lakes, decreased spring discharges, and decreased aquatic habitat in streams and lakes. Other impacts are increases in the risks from land subsidence and saltwater intrusion.

The U.S. Geological Survey began a system of monitoring stream discharge in the late 1800’s on many streams in the U.S. There are now continuous gages on over 7,000 streams, but a lack of stations with records of more than 30 years and a growing loss of gages on the smallest, unregulated streams, make it difficult to observe the impacts of drought on base-flow. In response to the drought of the 1930s, the USGS began monitoring water levels in a network of wells. Generally, this program has a more complete and extensive record in the Eastern U.S. than in the Western U.S. Some states use these wells as part of their drought management strategy.

Because of the lack of direct hydrological measurements of the impacts of recent droughts, it is useful to look at the hydrological impacts of land-use management to understand potential impacts on hydrological systems. There are good examples of changing agricultural practices and changing forest management practices to use as surrogates to understand the changes we might anticipate from drought. Also there may be animal taxa, such as spring snails, that may be very useful habitat indicators of long-term vegetation patterns, to understand drought on longer time scales.

The water in the Colorado River is fully subscribed, which will only exacerbate future drought conditions. There are a variety of demand tensions, including unprecedented population growth in the Southwest that need to be understood in order to develop viable plans for the region. International and Native American water rights claims/settlements need to be resolved and/or considered in drought plans that explicitly involve water use. There are supply tensions among political entities in the region that will have a major impact on dealing with basin wide drought. Sensitivity of snowpacks to climate forcings will be an important consideration in predicting future water availability. On-going water resource planning remains crucial for our future. Drought can exacerbate the potential for reactionary and politically motivated water planning. Systematic, basin wide natural resource planning that incorporates technical, policy and social knowledge is crucial for successful panning. For example, the Chesapeake Bay Program is a multi-state, multi-campus, multi-disciplinary program that exemplifies successful natural resource planning and management. This is one potential model that the Southwest should consider, in order to ensure that we are successful in developing future water supplies without compromising natural resources and quality of life for some communities in order to supply other communities.

Key Issues

1) There is a public perception that the resource is unlimited.

Ø The notion that one might have to pay higher water fees, but there is plenty of water to go around right now without a lot of thought towards the future

2) There is a need for adequate land use planning.

Ø Real estate planners, golf courses

3) Conversion of agricultural land to residential land.

Ø Apparently, residential land use uses more water then the previous agricultural uses of the land

4) A desire to preserve “the rural way of life” despite its current conflict with maintaining or creating sustainable conditions.

5) Impacts on hydrologic processes (recharge/storage)

Ø Increased runoff where trees and plants have been removed from the land cover, allowing water to keep moving over the land instead of going into the ground

Ø Increased Fire and

Ø bark beetle infestations

6) There exist short-term institutional barriers to water movement.

Ø Conservation practices

7) There is a need for better communication/outreach/interaction on water shortage/supply.

Ø Devise approaches to educating people on how to conserve water, where the water comes from, who is sharing the water with them, and why they should conserve

8) Urban/rural polarization must be reduced.

Ø Devise better communication between the urban and rural communities with regards to water use, water needs (i.e. livestock needs versus filling your swimming pool). The larger voting body is typically urban and thus rural needs and issues may be overlooked.

9) Regular stakeholder involvement in is needed more in the planning process.

Ø Allow greater public participation

10) Greater communication of hydrological issues to land managers is needed along with promoting greater public participation.

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12) The problems that arise with water availability in relation to a growing population must be taken into account.

Ø The growing population means more wells pulling out more water. How many wells can we put in the ground and on what evidence is this water use based? Can a community establish a population number, based on the water availability, beyond which there can be no more growth?

13) Need to evaluate the impact of drought on watershed scale, point monitoring (e.g., single wells) is not adequate.

Ø An example of this is wells drying up in Parks, Arizona

14) Further study of groundwater/surface-water interaction is necessary.

Ø Is ground water being withdrawn from wells near a flowing river impacting the river stage?

Ø For example, Chino Valley and the Verde River, or the Little Colorado River Basin

15) How will the dynamics of drought and decreased snow pack impact water availability?

Ø For example, increased temperatures

Ø Less snow means less recharge to ground water or run off to Lake Powell. How does this affect water use in communities?

16) It is necessary for many different constituents to understanding the water budget.

Ø Regional understanding of where the water from the tap is coming from. Learn how to communicate this to water managers and communities to help conserve water and/or limit growth

17) There needs to be centralized management and planning authority.

Ø Make sure all parties involved are making informed decisions based on sound information

18) A greater understanding of supply and demand is necessary.

Ø How much water is available and who needs it?

19) How does location affect water availability in certain communities?

Ø upstream vs. downstream

Ø water rights issues, water quality issues

20) More accurate information/indices are needed.

Ø Make sure the parameters and conditions under which the data were collected are well understood

Ø For example, long-term versus short-term surface water gauging data; or tree ring data; or paleo-climatic data)

21) Time scales for the information being collected and used in planning must be taken into consideration.

Ø Same concerns and suggestions as for #19

22) The integrity of spring, seep, and riparian ecosystems must be protect and preserved.

Ø Make sure riparian ecosystems are not adversely impacted by human needs

23) Protection of endangered species is necessary.

Ø Protection of the ecosystem(s) in which the species lives

Predictions

· Droughts are normal and will continue.

Ø Understanding that drought is part of the climatic cycle whether caused by anthropogenic or natural causes

· Less snow pack will decrease recharge to aquifers and reduce surface water availability.

Ø Fits into understanding the water budget and how drought affects the water used by a community and/or decisions made by City water managers

· Increased evapotranspiration (i.e., water transpired by plants) will occur with increases in temperature.

Ø Evapotranspiration removes a lot of water from a system. More plants lead to an increase in water loss

· Aquifers will continue to be drained regardless of drought conditions.

Ø Communities ignore drought conditions and continue with the same level of water usage as in non-drought conditions

· Policy links must be made between groundwater and surface water.

Ø Communities have to be pro-active and learn about the hydrologic connection between groundwater and surface water and make sound water use decisions based on this understanding

· The increase in population will result in an increase of ground water pumping.

· There will be an increase in sedimentation in existing reservoirs due to the impacts of fire in watersheds.

Ø Surface water runoff in areas where foliage has been removed by fire or other means will increase the salinity within the reservoirs from increases in the sediment being carried in with the water and diminish the water quality

Ø Decrease storage

Ø Decrease in water quality

· Changes in channel morphology will occur.

Ø Down cutting and/or aggradations

Ø Apparently, either process can occur in times of drought

· Groundwater usage and pumping will increase as it is no longer possible to create new surface-water reservoirs.

· Rivers, streams and washes will be negatively impacted by the continued loss of discharge from the groundwater systems due to a increased water use and a lack of recharge. This condition will be aggravated by the impacts if pumping in rivers and streams, and base-flow will be especially problematic near pumping centers.

· A greater use of alternative water supplies will need to occur.

Ø Recycled water, reclaimed effluent, and captured water, for example, storm water

Ø Gray water

· Water quality will continue to decline as wastewater is a soup of unregulated compounds.

Ø Know what is in your reclaimed/recycled water and which uses are reasonable

· We will work together---the population will respond.

· We will protect rivers, plants, animals.

· A change in the economic paradigm must occur so that growth is not the only valid indication of the future health of our country.

Manager Needs

· Define the triggers and thresholds of drought for clarification and identification purposes.

Ø Through dependable scientific means identify ways to measure aspects of the hydrologic system that clearly declare drought conditions

· Make data readily accessible as well as understandable, and easy to interpret.

· Researchers must produce information and materials in a timely manner.

· Create a comprehensive, integrated spring monitoring program.

Ø Identify vulnerable springs

Ø Establish monitoring program

· Assess hydrologic needs and concerns at the geographic scale of watersheds.

· Know and understand redundant water supplies, especially in rural areas.

· Understa