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Drought Indices in North America Richard R. Heim Jr

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Drought Indices in North America Richard R. Heim Jr Powered By Docstoc
					Drought Indices in North America

       Richard R. Heim Jr.
   NOAA/NESDIS/National Climatic Data Center
        Asheville, North Carolina, USA


     Inter-Regional Workshop on Indices and
        Early Warning Systems for Drought
          WMO/NDMC/NOAA/UNCCD/USDA
       Lincoln, NE, USA – December 8-11, 2009


                               National Climatic Data Center
           Historical Perspective

Droughts & Agriculture     Crop Failure, Famine,
Collapse or Abandonment of Early Civilizations




                             National Climatic Data Center
           Historical Perspective

Droughts & Agriculture     Crop Failure, Famine,
Collapse or Abandonment of Early Civilizations




                             National Climatic Data Center
           Historical Perspective

North America Today        Technology & Economic
Systems Mitigate Drought’s Impact on Agriculture, But
Drought Still Can Have Severe Economic Impacts




                              National Climatic Data Center
               Historical Perspective
The Drought Phenomenon
  Definition – Sectors Impacted – Indices
Early 20th Century Drought Indices
  Incorporated some measure of precipitation over a given time
  Examples:
   • 15 Consecutive Days with No Rain
   • 21 Days or More with Precipitation less than One-Third (or 30%) of
     Normal
   • Annual Precipitation less than 75% of Normal
   • Monthly Precipitation less than 60% of Normal
   • Any Amount of Rainfall less than 85% of Normal
  Other important climatic elements (soil
  moisture, evapotranspiration, etc.) were not
  readily available at that time

                                         National Climatic Data Center
               Historical Perspective
The Drought Phenomenon
  Definition – Sectors Impacted – Indices
Early 20th Century Drought Indices
  Incorporated some measure of precipitation over a given time
  Examples:
   • 15 Consecutive Days with No Rain
   • 21 Days or More with Precipitation less than One-Third (or 30%) of
     Normal
   • Annual Precipitation less than 75% of Normal
   • Monthly Precipitation less than 60% of Normal
   • Any Amount of Rainfall less than 85% of Normal
  Other important climatic elements (soil
  moisture, evapotranspiration, etc.) were not
  readily available at that time

                                         National Climatic Data Center
        (These Basic Indicators Are Still Widely Used Today)




http://www.agr.gc.ca/pfra/d
rought/mapscc_e.htm

                                     National Climatic Data Center
        (These Basic Indicators Are Still Widely Used Today)




http://www.agr.gc.ca/pfra/d
rought/mapscc_e.htm

                                     National Climatic Data Center
        (These Basic Indicators Are Still Widely Used Today)




http://www.agr.gc.ca/pfra/d
rought/mapscc_e.htm

                                     National Climatic Data Center
        (These Basic Indicators Are Still Widely Used Today)




http://www.agr.gc.ca/pfra/d
rought/mapscc_e.htm

                                     National Climatic Data Center
        (These Basic Indicators Are Still Widely Used Today)




http://www.agr.gc.ca/pfra/d
rought/mapscc_e.htm

                                     National Climatic Data Center
(These Basic Indicators Are Still Widely Used Today)




                             National Climatic Data Center
(These Basic Indicators Are Still Widely Used Today)




                             National Climatic Data Center
                   Historical Perspective
Mid-20th Century Improvements
  Evapotranspiration – Water Budget – Antecedent Precipitation
Palmer Drought Index (1965)
  Incorporated antecedent precipitation, moisture supply, & moisture
  demand in a (monthly) hydrologic accounting system using a 2-layer
  model for soil moisture
  Applied CAFEC (Climatologically Appropriate For Existing Conditions)
  Quantities to Normalize his Computations
   • Negative values → drought, positive values → wet spell
   • Comparison across space & time
         Short-Term Drought              Meteorological                 Hydrological
            (One Month)                    Drought                        Drought
                                         (PDSI, PMDI)                     (PHDI)




                                        National Climatic Data Center
                   Historical Perspective
Mid-20th Century Improvements
  Evapotranspiration – Water Budget – Antecedent Precipitation
Palmer Drought Index (1965)
  Incorporated antecedent precipitation, moisture supply, & moisture
  demand in a (monthly) hydrologic accounting system using a 2-layer
  model for soil moisture
  Applied CAFEC (Climatologically Appropriate For Existing Conditions)
  Quantities to Normalize his Computations
   • Negative values → drought, positive values → wet spell
   • Comparison across space & time
         Short-Term Drought              Meteorological                 Hydrological
            (One Month)                    Drought                        Drought
                                         (PDSI, PMDI)                     (PHDI)




                                        National Climatic Data Center
                Historical Perspective
Palmer’s Crop Moisture Index
(1968)
   Computed on a weekly basis for
   agricultural applications
Moisture Stress Index
   Developed in 2003 by NCDC
   Annual index for corn and soybeans
   that relates moisture stress (drought
   and extreme wetness) to crop
   productivity
   Computed from
   Palmer Z Index
   and crop yield
   Economic
   impacts
                                           National Climatic Data Center
                Post-Palmer Era
Indices Based On:
  Additional Observed Variables
  Advanced Statistical Methodologies
  More Sophisticated Models
  Data from New Observational Platforms




                                  National Climatic Data Center
    Surface Water Supply Index (SWSI)
Developed in 1981 for Colorado
(adopted by other Western States)
Integrates Snowpack, Reservoir
Storage, Streamflow, & Precipitation
at High Elevation
Standardized Units
Plotted by River Basin


                     http://www.wcc.nrcs.usda.gov/wsf/swsi.html




                                              National Climatic Data Center
  Standardized Precipitation Index (SPI)
Developed by Colorado’s McKee et al.
(1993)
Based on Probability Distribution of
Precipitation, with Normalization
Can Compute for Different Time Scales
for Differing Applications
                            http://www.ncdc.noaa.gov/oa/climate/research/prelim/drought/spi.html
                            http://www.wrcc.dri.edu/spi/spi.html



                                  http://www.agr.gc.ca/pfra/
                                  drought/mapscc_e.htm




                                         National Climatic Data Center
    Standardized Precipitation Index (SPI)
Can Express Droughts & Wet Spells in
terms of:
•   Precipitation Deficit
•   Percent of “Normal”
•   Probability of Non-Exceedence
•   Standardized Index Value (SPI)
Can Determine Drought Intensity,                 http://www.ncdc.noaa.gov/oa/climate/
                                                         research/prelim/drought/spi.html
Magnitude, & Duration, & Probability of          http://www.wrcc.dri.edu/spi/spi.html

Emerging from a Drought




                                     National Climatic Data Center
National Climatic Data Center
                            Soil Moisture
Soil Moisture Observation Networks Limited in U.S.




          http://www.wcc.nrcs.usda.gov/scan/
          http://www.cpc.ncep.noaa.gov/products/monitoring_and_data/topsoil.shtml
                                                       National Climatic Data       Center
                            Soil Moisture
Soil Moisture Observation Networks Limited in U.S.




          http://www.wcc.nrcs.usda.gov/scan/
          http://www.cpc.ncep.noaa.gov/products/monitoring_and_data/topsoil.shtml
                                                       National Climatic Data       Center
                                            Soil Moisture
      Rely on Modeled Soil Moisture




Leaky Bucket Model


http://www.cpc.noaa.gov/soilmst/leaky_glb.htm
http://www.cpc.ncep.noaa.gov/products/Soilmst_Monitoring/US/Soilmst/Soilmst.shtml
http://mrcc.sws.uiuc.edu/cliwatch/drought/moisture.htm                 National     Climatic Data Center
http://www.agr.gc.ca/pfra/drought/nlslmr_e.htm
                                            Soil Moisture
      Rely on Modeled Soil Moisture




Leaky Bucket Model


http://www.cpc.noaa.gov/soilmst/leaky_glb.htm
http://www.cpc.ncep.noaa.gov/products/Soilmst_Monitoring/US/Soilmst/Soilmst.shtml
http://mrcc.sws.uiuc.edu/cliwatch/drought/moisture.htm                 National     Climatic Data Center
http://www.agr.gc.ca/pfra/drought/nlslmr_e.htm
                                            Soil Moisture
      Rely on Modeled Soil Moisture




Leaky Bucket Model


http://www.cpc.noaa.gov/soilmst/leaky_glb.htm
http://www.cpc.ncep.noaa.gov/products/Soilmst_Monitoring/US/Soilmst/Soilmst.shtml
http://mrcc.sws.uiuc.edu/cliwatch/drought/moisture.htm                 National     Climatic Data Center
http://www.agr.gc.ca/pfra/drought/nlslmr_e.htm
    Using Soil Moisture Models to Monitor Drought
       at the NOAA Climate Prediction Center

   “Leaky Bucket” model: a 1-layer                    NLDAS 1-m and 2-m soil column; 4
   hydrological model. Uses observed precip.          separate models and ensemble;
   and temps to calculate soil moisture for a         versions produced by NOAA EMC and
   soil column of 1.6 meters.                         the University of Washington




http://www.cpc.noaa.gov/soilmst/leaky_glb.htm   http://www.emc.ncep.noaa.gov/mmb/nldas/drought/

       http://www.hydro.washington.edu/forecast/monitor/curr/conus.mexico/main_sm.shtml
                                                     National Climatic Data Center
         North American Land Data
        Assimilation System (NLDAS)
 The NLDAS is a multi-institution collaborative project sponsored by
 the Climate Prediction Program of the Americas (CPPA). The
 institutions are composed of NOAA’s National Centers for
 Environmental Prediction (NCEP), NASA’s Goddard Space Flight
 Center (GSFC), NOAA’s Office of Hydrologic Development (OHD),
 Princeton University, and University of Washington.

The NLDAS uses four land surface models: Noah, Mosaic,
SAC and VIC.


Four models are run in near real-time at the NCEP’s
Environmental Modeling Center to provide output products
to support the US National Integrated Drought Information
System (NIDIS) and US Drought Monitor.
                                        National Climatic Data Center
       Using the NLDAS Ensemble Mean Soil
          Moisture as a Drought Indicator
              Shallow layers of soil moisture can be used as
              agricultural drought indicators. Model runoff
              as hydro indicators.
                         Ensemble Mean

NCEP                                                                       NASA
Noah                                                                       Mosaic




                                                                     Princeton
                                                                     VIC
OHD SAC
                Percentile soil moisture levels
                correspond to U.S. Drought
                                     National Climatic Data Center
                Monitor levels D0 to D4 http://www.emc.ncep.noaa.gov/mmb/nldas/drought/
U.S. Seasonal Drought Outlook




   Issued twice monthly
       by NWS/NCEP




                          National Climatic Data Center
   Improved Drought Forecasting and Early
                 Warning
NLDAS models can be linked to downscaled seasonal forecast
models to produce drought probability forecasts

                                                          NOAA’s Climate
                                                          Prediction Center is
        Forecast Drought Probability for February 2010    working with its
                                                          partners to develop
                                                          operational numerical
                                                          drought forecast
                                                          products.




                                         National Climatic Data Center
 USGS-EROS Early Warning & Environmental Monitoring
Drought Monitoring using
the VegET Model:
• Conducts daily water
  balance computations by
  pixel (5km-25km depending
  on input dataset)
• Output for operational
  vegetation water balance
  modeling
• Products include: Soil
  Water Index (SWI), Water
  Requirements Satisfaction
  Index (WRSI), and 3 ETa
  (actual evapotranspiration)
  products

                                National Climatic Data Center
   NOAA/NWS Advanced Hydrologic Prediction Service

Hybrid Product Integrates Radar Precipitation Estimates
with In Situ Rain Gage Measurements




       http://water.weather.gov/index.php   National Climatic Data Center
   NOAA/NWS Advanced Hydrologic Prediction Service

Hybrid Product Integrates Radar Precipitation Estimates
with In Situ Rain Gage Measurements




       http://water.weather.gov/index.php   National Climatic Data Center
               U.S. Objective Blends
Developed as support for U.S. Drought Monitor
Operationally integrate multiple indicators in a weekly
update using a percentile ranking method
Produced weekly using CPC’s real-time daily and weekly
climate division data and NCDC’s monthly archive of
indices for 1932-2000
All parameters are first rendered as percentiles with
respect to 1932-2000 data using a percent rank method
The parameters (drought indicators) are then combined
using a weighting scheme
Short- and Long-Term Blends produced



                                 National Climatic Data Center
National Climatic Data Center
   FMDI – Floating Month Drought Index
FMDI – a new drought index to provide guidance on drought
termination amidst conflicting indicators
Inspired by the Australian decile-based drought definition,
USDM, & Objective Blends
Based on precipitation percentiles
Being developed by NCDC




                                  National Climatic Data Center
    FMDI – Floating Month Drought Index
Dry Spell begins – when 3 consecutive months each have an
anomaly <= 30th percentile and the anomaly of total precipitation
for the 3 consecutive dry months falls beyond the cutoff (<= 30
percentile)
Dry Spell ends when:
   the total precipitation for the months from
   beginning anchor year-month to current
   month no longer falls beyond the cutoff (<=
   30th percentile), OR
   the precipitation for the past 3 months is
   extremely wet (3-month total precipitation
   >= 70th percentile)
Similar triggers for wet spell
Modification for exceptionally dry seasons

                                        National Climatic Data Center
        FMDI – Floating Month Drought Index




Precipitation percentiles & Dx/Wx categories   Length (number of consecutive months) and
    for current N-month wet & dry spells       begin year/month of current wet & dry spells


                                                     One-month precipitation percentile
                                                            for current month



                                                  National Climatic Data Center
              Hydrologic Indices
Based on Streamflow or
Groundwater
Groundwater Observing Network               http://watermonitor.gov/
Coarse




                                National Climatic Data Center
                       Hydrologic Indices
Based on Streamflow or Groundwater
                                                                                 Flood
Streamflow – Need to Remove Peak                                                 Monitoring

Flow from Hydrograph
• Streamflow-based drought indicators
  usually based on low-flow (base flow) or
  some averaged flow                                                          Drought
                                                                              Monitoring




          14-Day Average Streamflow                       Monthly Average Streamflow




                                       National Climatic Data Center
                                                         http://watermonitor.gov/
                             Hydrologic Indices
Based on Streamflow or Groundwater
Reservoir Data                                          http://watermonitor.gov/

 • State data, no national access system
 • Managed for different purposes (irrigation, urban water supply, flood
   control, etc.)




Arizona reservoir levels,
September 2009, percent of               National Climatic Data Center
capacity.
   Remotely-Sensed (Satellite-based) Indices
  Provide Global Coverage
  Spatially Consistent
  Reflected Intensities at Specific
  Wavelengths


                                               http://www.agr.gc.ca/pfra/drought/
                                               mapscc_e.htm




http://www.star.nesdis.noaa.gov/
smcd/emb/vci/VH/index.php

                                      National Climatic Data Center
     Vegetation Drought Response Index (VegDRI)
 Hybrid Drought Index that Integrates:
       Satellite-based observations of vegetation conditions
       Climate-based drought index data
       Biophysical characteristics of the environment
                                     http://drought.unl.edu/vegdri/VegDRI_Main.htm




                                             National Climatic Data Center
(Source: Wardlow, 2008)
                 Paleoclimatic Drought Indices
     Based on Tree-Ring Data
     Extends Period of Record for
     Historical Comparisons
     Gridded Reconstructions
                 PDSI
  DRY                   WET




Drought
Reconstruction                  http://www.ncdc.noaa.gov/paleo/treering.html
for 1863                                  National Climatic Data Center
         Impacts (Producer Survey) Indicators




http://droughtreporter.unl.edu/




  http://www.cpc.ncep.noaa.gov/products/predictions/experimental/
  edb/pasture-range-statewide-conditions.pdf
http://www.agr.gc.ca/pfra/drought/pr_e.htm



                                                           National Climatic Data Center
         Impacts (Producer Survey) Indicators




http://droughtreporter.unl.edu/




  http://www.cpc.ncep.noaa.gov/products/predictions/experimental/
  edb/pasture-range-statewide-conditions.pdf
http://www.agr.gc.ca/pfra/drought/pr_e.htm



                                                           National Climatic Data Center
         Impacts (Producer Survey) Indicators




http://droughtreporter.unl.edu/




  http://www.cpc.ncep.noaa.gov/products/predictions/experimental/
  edb/pasture-range-statewide-conditions.pdf
http://www.agr.gc.ca/pfra/drought/pr_e.htm



                                                           National Climatic Data Center
         Impacts (Producer Survey) Indicators




http://droughtreporter.unl.edu/




  http://www.cpc.ncep.noaa.gov/products/predictions/experimental/
  edb/pasture-range-statewide-conditions.pdf
http://www.agr.gc.ca/pfra/drought/pr_e.htm



                                                           National Climatic Data Center
         Impacts (Producer Survey) Indicators




http://droughtreporter.unl.edu/




  http://www.cpc.ncep.noaa.gov/products/predictions/experimental/
  edb/pasture-range-statewide-conditions.pdf
http://www.agr.gc.ca/pfra/drought/pr_e.htm



                                                           National Climatic Data Center
                    NIDIS Drought Portal
    A Web-Services-Based Drought Information & Data System, for
    the U.S.                             http://drought.gov
•    Current conditions
•    Forecasts
•    Impacts
•    Planning
•    Education
•    Research
    Going International with
    NADM Data and
    Services
    Working with UN on int’l
    drought early warning &
    international
    clearinghouse
                                    National Climatic Data Center
                    NIDIS Drought Portal
    A Web-Services-Based Drought Information & Data System, for
    the U.S.                             http://drought.gov
•    Current conditions
•    Forecasts
•    Impacts
•    Planning
•    Education
•    Research
    Going International with
    NADM Data and
    Services
    Working with UN on int’l
    drought early warning &
    international
    clearinghouse
                                    National Climatic Data Center
U.S.-Canadian GEO Bilateral Drought Studies
 5 testbeds/projects approved by the bilateral US-
 Canada GEO Committee at its May 2009 meeting:
   Three international, interdisciplinary water-related monitoring
   testbeds, building on existing initiatives, along the U.S.-
   Canada border:
       Great Lakes        Prairie Region            Rocky Mountains

   Two studies of drought in the context of hazards and
   extreme events:
      Drought Definitions and Indices Study
      Surface Water Supply Index (SWSI) Study
   Charters being developed                    Richard.Heim@noaa.gov



                                      National Climatic Data Center
U.S.-Canadian GEO Bilateral Drought Studies
 Drought Definitions and Indices Study
    Improved definition of drought for different climatic regions needed, &
    new & improved indices for drought needed
    Continent-wide study for
    comparative analysis
    across regions, with
    close links to testbed
    activities
    58 participants involved
    GEO Drought Indices
    community set up on
    NIDIS drought portal

  Richard.Heim@noaa.gov



                                          National Climatic Data Center
The 2010 NADM and Global Drought Forum

Location: Asheville, NC, USA
When: April 20-23, 2010                   Richard.Heim@noaa.gov

Session/Agenda Topics:
  NADM technical & administrative issues
  NADM user issues & general drought issues
  The NIDIS Drought Portal as a platform for expanded
  international drought monitoring, global drought early
  warning system
  U.S.-Canadian GEO bilateral testbeds & drought studies


                                  National Climatic Data Center
                        Thank You!
                      Richard.Heim@noaa.gov

      NCDC Climate Monitoring Branch Reports & Products:
  http://www.ncdc.noaa.gov/oa/climate/research/monitoring.html

                NCDC State of the Climate Reports:
                 http://www.ncdc.noaa.gov/sotc/

                  North America Drought Monitor:
http://www.ncdc.noaa.gov/oa/climate/monitoring/drought/nadm/index.html

                       U.S. Drought Monitor:
              http://drought.unl.edu/dm/monitor.html

                                NIDIS:
                         http://drought.gov/
                                       National Climatic Data Center

				
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