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Drought Predictability in Mexico. Francisco Muñoz Arriola 1 , Shraddhanand Shukla 1 , Lifeng Luo 2 , Abel Muñoz Orozco 3 , and Dennis P. Lettenmaier 1 1 Department of Civil and Environmental Engineering, University of Washington
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Drought Predictability in Mexico Francisco Muñoz Arriola1, Shraddhanand Shukla1, Lifeng Luo2, Abel Muñoz Orozco3, and Dennis P. Lettenmaier1 1Department of Civil and Environmental Engineering, University of Washington 2Department of Civil and Environmental Engineering, Princeton University 3Colegio de Posgraduados American Meteorological Society Phoenix, AZ January 12th 2009
Outline • Motivation • Mexican Droughts • Objectives • The University of Washington West-wide Forecast System • Drought assessment • Soil Moisture Percentile, Standardized Precipitation Index (SPI) and Standardized Runoff Index (SRI) assessments • Conclusions • Future Work
Physical Features • More than 70% of its surface is considered topographically steep • Has the largest biological diversity, natural and agricultural (e.g. corn) found in North America • Precipitation regimes dominated by summer events (with different spatiotemporal patterns) • Various drought periods along the year Source: Instituto Nacional de Estadistica e Informatica (INEGI)
Hail 0.01% Frozts 0.52% Rainfall 2.05% Hurricanes 79.62% 17.81% Drought 0 20 40 60 80 Source: SAGARPA. 1995-2004 Agricultural Damages by Hydrometeorological Phenomena • Great part of the agriculture is unirrigated • 44% during the Fall-Winter cycle • 84% during the Spring-Summer cycle • The largest damages are related to hydromet. Phenomena • Interannual differences in the spatial patterns of drought occurrence
Great winter drought (3 and 4) • winter and part of the spring • Affects moisture availability for crop seeding • Distribution, same as MSD • Mid-summer drought (3 and 4) • Eastern of Sierra Madre Occidental, Central and Southern Mexico • Decrease in rainfall (July-August) • Affects flowering in Mexican unirrigated croplands • Pre-monsoonal drought (2) • Spring drought over Northwestern Mexico • Affects water storage and irrigate agriculture • Mediterranean drought (2) • Occurs in areas of Mediterranean climates • Affects agriculture and water availability in the Peninsula of Baja California • All over the year except Fall and Winter Droughts in Mexico 2 3 1 4 • Mexico • Northwestern • North Central • South
Research Questions Due to the reduced availability of information regarding drought predictability and given the impacts of this condition in Mexico we aimed to answer the following questions • Are there changes in the seasonal predictability of drought given the initial conditions along the year 2007? • How drought predictability varies in different parts of Mexico? • Are there differences between the Ensemble Streamflow Prediction (ESP) and the Climate Forecast System?
OBJECTIVE • Evaluate the seasonal drought predictability in Mexico at different sub-domains through the use of the UW Extended West-wide Seasonal Hydrological Forecast System • Apply the ESP and CFS to distinguish differences in drought predictability
UW Extended WSHFS and ESP • Based on the use ensemble techniques applied to generate forcing data for a Land-surface hydrology model
VIC VIC VIC Drought Predictability Assessment 2007 Initializations Mar, May, Jul, Sep, Nov ESP CFS 1971-2000 1971-2000 NCAST Long-term Historical Observed Atmos. Forcing Realtime Atmos. Forcing Modelling-based Atmos. Forcing + Long-term Long-term Hydrological States Realtime Hydrological States CFS-Long-term Hydrological States Mexico, North Central, Northwest, andSouth RMSE OBS (NCAST) and Forecast (ESP and CFS) Soil Moisture Percentiles (SMI) ESPs , CFSs, and Nowcast
Ensemble Performance (soil moisture Percentiles) Observations Forecasts Initial Conditions March ESP CFS April May June 2007
Drought Predictability ESP Initialization Month RMSEforecast RMSEforecast/RMSEclimatology 1-month lead 2-month lead 3-month lead Forecast Month
Forecast and North American Drought Monitor March 3-m L May 1-m L June Initial Conditions Month-lead May 2-m L ESP Mexico July May 3-m L July 1-m L August
Monitored Drought Indices (ESP) for August 2007 Soil moisture Percentile-Forecast Standarized Precipiatation Index North American Drought Monitor Soil Moisture Percentile-Observations Standarized Runoff Index Shukla and Wood (2008)
Conclusions • Differences in the predictability along Mexico showed • The largest drought predictability occurred in North-central Mexico, while the lowest occurred in the South. • Largest values of RMSE were observed during the Summer period in all sub-domains • Low RMSE values indicate high skill in the forecast for those initialized late in the Fall • Initialized in March 2007, ESP and CFS performances show spatial differences, while ESP outperforms CFS in general, over particular domains such as in South Mexico CFS outperform ESP. • The UW-West-wide Hydrological Forecast System registered drought events recorded by the NADM plus other events reported by Mexican agencies regarding agriculture impacts of drought in parts of Baja California Peninsula, San Luis Potosi, Michoacan, and Northern Oaxaca
Future Work • Evaluate the interannual variability in the ESP and CFS performances to complement the drought predictability assessment • Involve more land surface models through the application of the University of Washington Surface Water Monitor, which uses (NOAH, LCM, and SAC models to monitor and predict drought (its development is currently in progress). • Evaluate the drought predictability over a larger domain
Thank you! Tlaloc, the Aztec God of Rain, responsible of drought and flood (Borgia Codex)
I.C. Initialization Month Observations Forecasts 1-month lead 2-month lead 3-month lead cccc cccc cccc Forecast Month
I.C. Initialization Month Forecasts Observations 1-month lead 2-month lead 3-month lead Forecast Month
Climatology vs Forecast RMSEforecast/RMSEclimatology
Water Balance North Central Northwest March May Observed Forecast