Drought Activities at the NOAA/NCDC Climate Monitoring Branch Richard R. Heim Jr. Jay H. Lawrimore NOAA/NESDIS/National Climatic Data Center Asheville, North Carolina USDM Workshop Portland, OR, October 2007

Overview Monthly State of the Climate drought reports Drought Monitor Activities (USDM, NADM) FMDI – Floating Month Drought Index Living Blended Paleo Drought Monitoring NIDIS International Drought Monitoring – Drought Early Warning System

State of the Climate Drought Reports Monthly reports Narrative & graphics NOAA press release, plus: Global Analysis, Global Hazards & Significant Events, National Overview, Drought, Wildfire, Hurricane sections Drought has U.S. focus Online by mid-month (12th to 15th)

CMB Drought Web Pages Drought Monitoring Tools A static page that provides links to drought web resources from other organizations Drought Termination in the U.S. Based on Palmer Drought Index Precip required to end/ameliorate drought & probabilities of it occurring Weekly maps Plot of indicators derived from CPC weekly data Monthly Palmer Drought Index computed weekly

Drought Monitor (USDM/NADM) Activities Author U.S. Drought Monitor (USDM) and North America Drought Monitor (NADM) Host the NADM web site: http://www.ncdc.noaa.gov/oa/climate/monitoring/drought/nadm/index.html Compute the continental indicators for the NADM U.S., Canadian, Mexican SPI, PCTPCP, & Palmer Drought Indices

Transitioning from Climate Divisions to Station Data for the U.S. One of the action items from Oct 2006 NADM Workshop For NADM drought indicator maps, have used stations for CN & MX & AK, climate divisions for contiguous U.S. We are now also computing/plotting the North America indicator maps using stations for contiguous U.S. Stations in U.S. Climate divisions in U.S. Stations in U.S.

Precipitation Climatologies for N. America Percent of annual precipitation maps Monthly, 3-Month Seasons, 6-Month Seasons

FMDI – Floating Month Drought Index FMDI – a new drought index inspired by the Australian decile-based drought definition and the USDM Based on precipitation percentiles Computes: Precipitation percentile for current month Length (number of consecutive months) and begin year/month of current dry spell Precipitation percentile for current N-month dry spell Dx dry spell category (based on USDM categories) for current month Length (number of consecutive months) and begin year/month of current wet spell Precipitation percentile for current N-month wet spell Wx wet spell category (based on analog to USDM categories)

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)

FMDI – Floating Month Drought Index Wet Spell begins – when 3 consecutive months each have an anomaly >= 70th percentile and the anomaly of total precipitation for the 3 consecutive dry months fall beyond the cutoff (>= 70 percentile) Wet Spell ends when: the total precipitation for the months from beginning anchor year-month to current month no longer falls beyond the cutoff (>= 70th percentile), OR the precipitation for the past 3 months is extremely dry (3-month total precipitation <= 30th percentile)

FMDI – Floating Month Drought Index Has a Near-Real Time component and a Backstepping component Requires serially complete data

FMDI can show Wet Spell Conditions as well as Dry Spell.

FMDI – Floating Month Drought Index

FMDI Correlations With Other Drought Indices INDEX ALL MONTHS 1/1931-5/2007 JUN 07 JUL 07 AUG 07 6/2007-8/2007 PMDI 0.711 0.757 0.719 0.759 0.743 PHDI 0.656 0.738 0.681 0.728 0.713 PDSI 0.686 0.733 0.683 0.712 Z Index 0.617 0.584 0.643 0.736 0.652 SPI – 1 0.554 0.561 0.513 0.649 0.566 SPI – 2 0.690 0.609 0.725 0.663 SPI – 3 0.781 0.756 0.795 0.776 SPI – 6 0.754 0.735 0.777 0.755 SPI – 9 0.657 0.676 SPI – 12 0.606 0.680 0.634 0.655 0.654 SPI – 24 0.460 0.525 0.434 0.538 0.499 USDM 0.430* 0.651 0.564 0.623 * 1/2003-5/2007

Living Blended Paleo Drought Monitoring The instrumental data record extends back only about 100 years Paleoclimatic data can extend our drought historical perspective back several hundred to thousands of years Based on station meteorological data Based on tree ring chronologies

Building the Living Blended Paleo Drought Data Base Station data network across U.S., Canada, & Mexico Monthly Max & Min Temperature & Precipitation Gridded monthly temp, precip, & PDSI 0.5 x 0.5 degree lat/lon grid Computed for the instrumental period of the 20th Century

0.5 x 0.5 degree latitude/longitude grid for monthly temperature, precipitation, drought indices ~ 11,400 gridpoints

Building the Living Blended Paleo Drought Data Base Paleoclimatic (tree ring) data base across the U.S., Canada, & Mexico Spans the period from the late 20th Century back several hundred years

Building the Living Blended Paleo Drought Data Base Point-by-point regression method Applied to the 20th Century period common to both data bases To develop regression equations relating the tree ring chronologies to the instrumental period gridded PDSI This allows reconstruction of gridded PDSI for the pre-20th Century period covered by the tree ring data

Living Blended Paleo Drought Monitoring Creating the “Blend” The gridded reconstructed PDSI data from the paleo record can be “stitched to” or “blended with” the gridded PDSI computed from the instrumental data The instrumental gridded PDSI will be updated operationally on a monthly basis Thus, the paleo-instrumental gridded blend is a “living” drought data base

Living Blended Paleo Drought Monitoring Monitoring Products – Gridded Data Base

NIDIS – National Integrated Drought Information System NCDC / Climate Monitoring Branch: Leading the NIDIS Drought Portal Conceptual and Social Design Team Providing recommendations for and review of the Portal content Providing programming support for the development of the Portal

International Drought Monitoring – Drought Early Warning System (DEWS) Drought does not respect political boundaries Water availability is emerging as a critical concern for the 21st Century There are projections of potential increases in the frequency & intensity of drought due to climate change, coincident with population increases An International Drought Early Warning System would enable the global community to give a coordinated response to the drought problem

International Drought Monitoring – Drought Early Warning System (DEWS) November 30 GEO Ministerial Summit in Cape Town, South Africa The Cape Town Summit is one of the early efforts to introduce the concept of a global drought early warning system to other countries Video presentation, exhibit, and discussion planned to discuss the NADM, NIDIS, & how they fit into a Drought Early Warning System Video will include NADM interviews with Canadian & Mexican partners Tabletop book (“GEO – The Full Picture”) will be published in advance for Summit distribution – will include an NADM / DEWS chapter Each Nation would need to evaluate their level of DEWS involvement – Ministerial support needed

International Drought Monitoring – DEWS Objectives: An International Drought Information System that weaves together current and future observation systems from participating Nations to provide: An early warning system for drought Information for drought response, planning, mitigation, and recovery An interactive, web-based drought portal and analysis tools Provide critical drought information to countries with inadequate monitoring resources Goals: A system of systems for data & information sharing, communication, & capacity building to take on the growing worldwide threat of drought Regular drought warning assessments issued as frequently as possible with increased frequency during a crisis

International Drought Monitoring – DEWS Build upon the groundwork laid by GEO (Group on Earth Observations) and GEOSS (Global Earth Observation System of Systems) Could be patterned after the North America Drought Monitor (NADM) and U.S. National Integrated Drought Information System (NIDIS) A Drought Early Warning System requires a GEO commitment Operational responsibilities Research collaboration for developing new monitoring, analysis, and forecasting technologies Many nations have important components of a drought early warning system. No one nation has all the tools, products, and data to deliver the best system.

Thank You! 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/oa/climate/research/monitoring.html#state 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/