Drought Challenges and Opportunities
                                 R. Dole, CDC
                           Plus a cast of thousands*

                                                North Platte river, May 22, 2002
    Drought in Great Plains, ca. 1935           Mean flow - 1310 cfs, Observed - 0

*J. Laver, D. Lecomte, A. Kumar, T. Karl, J. Lawrimore, R. Heim, R. Livezey, M. Brewer,
C. Nierenberg, J. Foster, H. Hill, N. Beller-Simms, C. Woodhouse, R. Webb, K.         1
Redmond, et al.
                                                                  May 21, 2004
                   Fundamental Challenges of Drought

               Human/Environmental Dimensions
 Droughts are not simply climate phenomena. They have profound social,
environmental, and economic impacts. This vastly increases challenges to

1988 Drought

1980 Drought

                 Fundamental Challenges of Drought

• Definition: There is no unique definition of drought.
National Drought Policy Commission: Drought is
“ A persistent abnormal moisture deficiency having adverse impacts on
vegetation, animals, and people”.

• There are different drought “types”.
   Meteorological - Prolonged rainfall deficit compared to normal.
   Agricultural - Topsoil moisture deficit. Agricultural impacts.
   Hydrological - Surface or sub-surface water supply shortage.

Typically, meteorological         agricultural            hydrological
Same sequence for drought recovery.

                     Fundamental Challenges of Drought
                          Diverse time scales


                             Other climate modes

Droughts span an enormous range of time scales, from short-term “flash droughts” that
can have major agricultural impacts to multi-year or even decadal droughts (1930s,
1950s, etc.) Paleoclimate evidence suggests that in the last 1000 years parts of the
U.S. have experienced “mega-droughts” that persisted for decades.
       Drought evidence in Paleoclimate Records
                   (from NCDC Paleoclimate Branch website)

  From tree ring
  Records - NM

From salinity
estimates -
Moon Lake, ND

                         Strategic Challenges
 Governmental entities are moving from simply responding
to droughts to more proactive approaches.
   The U.S. is moving toward a more proactive approaches to anticipating and
   managing droughts. This has important implications for future NOAA
   climate services --

 Droughts have profound national and global implications.
   Severe and sustained droughts can lead to legal and political conflicts. For
   example, prolonged drought in the U.S. Southwest and northern Mexico is
   creating toward conflicts about shared water rights.

 Demands for scientifically-based drought information are
   The needs for drought information now extend beyond traditional drought-
   sensitive sectors such as agriculture and water resource management.
   There are increasing needs for drought information to inform critical policy
   and infrastructure decisions, and increasing concerns about the potential
   impacts of human-induced climate change on future water supply.             6
                         And Opportunities …
 NOAA has tremendous scientific and service capabilities related to
drought. We have developed significant cooperation across lines to
address drought challenges, from drought monitoring to planning and
cooperation with the Western Governors’ Association for a National
Integrated Drought Information System (NIDIS).
 Beyond NIDIS, there are numerous other national and international
drivers that reinforce the needs for improved drought monitoring, prediction,
and information services. Several of these will be discussed later. They
    • CCSP - extreme events and regional decisional support.
    • CENR - grand challenges for the next decade (extreme events/drought).
    • Pending drought legislation in the House and Senate.
    • GEO - improved observing systems for decision support.
    • Other international - North American and International Drought monitors.
Without question, there are major opportunities for NOAA to
contribute in the above areas. Also without question, the provision of
drought information will be a major part of NOAA’s future climate
       A Specific Example: Drought in the West

•The western drought is a hydrologic drought.

•This is a sustained drought. It has developed over several years.

•This is a large-scale drought. It affects much of the western U.S.

•This is a severe drought - at least by modern historical terms.

•This drought is attracting heavy media attention, including from
major national media outlets.

•The drought is raising grave management concerns.
There is discussion of the possibility for the first-ever “call” on the
Colorado River under the terms of the Colorado River Compact.

                            Severe Hydrologic Shortages
                               • Lake Powell is at 42% capacity
                               • Lake levels have dropped ~ 120 feet
                               • Reservoirs above Lake Powell are
                                 currently at 62% of capacity
                               • Net flow of water for WY 2004 to date is
                                 58% of average.

Glen Canyon Dam                    Lake Powell Water Level (ft)





                  3400                                                                 9
                     1960   1965   1970   1975    1980    1985   1990   1995   2000   2005
Dillon Reservoir

      Potential Western water supply crises
          and conflicts by 2025 (USBR)

US Bureau of Reclamation analysis of potential water supply crises and conflicts by
the year 2025 based on a combination of technical and other factors, including
population trends and potential endangered species needs for water.
Note: There is an underlying assumption of a statistically stationary climate.
          Overview of NOAA Drought Products

There are numerous NOAA drought products available, which are very
heavily used. Only a few examples will be shown here, to serve as
updates on the current situation and to provide a basis to discuss
challenges and opportunities for NOAA climate services.

There is an excellent central NOAA website available for those interested:


This drought information center contains links to sites across NOAA that
provide real-time information as well as background materials on drought.

                       U.S. Drought Monitor
              Derived by synthesizing various information sources
                (NOAA leads: CPC, NCDC. With DOA and NDMC)

Agricultural (A), hydrological (H) designate primary impacts (drought types). There
are manifold indirect impacts as well, e.g., on recreation, energy production, water
quality, fire risk, air quality, ecosystems, endangered species.                   13
NOAA Drought Outlook

                      Paleoclimate Products
                           (NCDC-Paleoclimate Branch)
Gridded Reconstructions of Drought (PSDI),
            Cook et al. 1999
• Annual maps and grid point time series from
reconstructed (1700-1978) and instrumental
(1900-1995) data, available online.
• Updated version soon to be released, expanded
to North America, back to AD 800 (many areas),
reconstructions are integrated with instrumental
data to up to 1999.
• Recently funded, “living” blended drought
reconstructions will be updated with instrumental
data for nearly “real time” assessments of current
and developing drought in a long-term context.

               Applications of Paleoclimate data
• Is the Colorado River Compact based on a period of
anomalous moisture? Is the current drought, which
has drawn Lake Powell down to less than half its
capacity, an unusual event? The Colorado River at
Lees Ferry reconstruction can answer the first
question (Yes), but it ends in 1964. There are plans to
update this reconstruction and others for the Colorado
River basin to 1999 or later.
• What measures are required to bring groundwater
pumping, which has driven groundwater to the lowest
depths since pumping began in the San Luis Valley, in
balance with inflows? Gauge records are too short to
determine the long-term natural variability of
droughts, which must be considered when evaluating
the sustainability of the aquifers underlying the valley.
Tree-ring reconstructions can provide information on
long-term inflows.

                                                            Grand Canyon and       16
                                                            Great Sand Dunes NPs
             Regional Climate Center Products
   • The Western Region Climate Center (WRCC) in Reno is a tremendous
   resource for climate information relevant to the western drought. In addition
   to providing drought-related products through its website, WRCC personnel
   interact extensively with end users to address questions on drought and
   other related issues, such as wildfires.

Some WRCC products

• Historical Climate Data
• Real-time monitoring products
• Current obs. and forecasts
• Educational pages
• Research products

       Regional Integrated Science and Assessments
  The RISAs provide a direct connection between research and end users.
  They have a strong focus on drought issues, how current climate
  products are used and interpreted, and what are the needs for next
  generation regional climate information products.

RISA research is:
• User focused
• Interdisciplinary
• Place-based
• Considers multiple stressors
• Focuses on key regional issues
• Provides and assesses uses of
climate information and products
for regional decision support

        International Products and Linkages

• GEO – Organized by Themes Including
         Climate
         Natural Hazards and Disasters
         Agriculture
         Water Resources
• Experimental Drought Monitor Product
         Mexico
         Canada
• Issues Related to Operational Product
         Observation Systems
         Data Timeliness & Quality
         Drought Indices/Tools
         Coordination Among Principals
• Potential for Early GEO Success
         International October Meeting
               Existing/Planned Products
       NOAA Drought-related Research
• What are potential sources for drought predictability?

• What are observed climate trends, and can their causes be identified?

• What are projections for future climate change, and what is our
confidence in such projections?

• How are climate products now used, what are their strengths and
limitations, and how can these products be improved or new products be
developed that will better serve the needs of the public and decision-

Drought-related research is being carried out a several institutions, and
also supported at OGP, especially through water-cycle research in the
Climate Prediction Program for the Americas (CPPA), with a summertime
precipitation focus in the North American Monsoon Experiment (NAME).

   Effects of ENSO on SW U.S. Precipitation

• Climate forecasts are intrinsically probability forecasts.
• Beyond a few weeks the major source for predictive skill comes from
ocean conditions in the tropical Pacific-Indian Oceans.                 21
What are Observed Western Climate Trends?

 Observed and modeled SW winter temperature trends

Observed trends are consistent with trends obtained in climate
models forced by observed GHG changes. However, models forced
by observed SST over this period also show warming, so both
anthropogenic and natural factors are likely contributing.
           Western U.S. Streamflow Trends

               From Stewart, Cayan, and Dettinger (2004)

There is a marked trend toward an earlier melt out and earlier peak flows
throughout almost all of the West, consistent with a winter warming trend.
Such warming increases evaporation, extends the growing season, and
likely also increases the demand for water resources.                        24
    U.S. West climate trends projections
from transient-forced runs (8 models, 12 runs)

Projected temperature and precipitation trends

                             NIDIS Update
National Drought Preparedness Act of 2004
    Establishes a permanent Drought Council
    Authorizes a Drought Fund
    Gives the lead for implementing the NIDIS to DOC/NOAA

NIDIS Recommendations
1) Establish NIDIS
2) Establish data needs and integration tools - integrate existing
     networks, determine gaps …
3)   Research Needs …. to improve the forecasting of short- and long-term
     drought conditions, to make the forecasts more useful and timely, and to establish
     priorities based on the potential to reduce drought impacts.

4)   Facilitate Drought Preparedness Programs
5)   Enhance Interactions and Education
        Key issues and questions
• In the near-term, should NOAA develop a more
   integrated strategy in anticipation of emerging issues
   related to the western U.S. drought?

• How will NOAA respond to the NIDIS challenge?

• There has been good collaboration within NOAA and
   with other agencies on the drought problem. However,
   many of the collaborations are ad hoc and could be
   better developed. How will NOAA develop a more
   integrated strategy so that we are providing even
   better drought information services than we do now?

The End


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