DEVELOPMENT OF A HIGH-RESOLUTION DROUGHT TRIGGER TOOL (HIDRTT) FOR THE UNITED STATES

• Sponsoring Institution: National Institute of Food and Agriculture
• Project Status: COMPLETE
• Funding Source: AFRI COMPETITIVE GRANT
• Reporting Frequency: Annual
• Accession No.: 0224092
• Grant No.: 2011-67019-20042
• Cumulative Award Amt.: $496,335.00
• Proposal No.: 2010-03559
• Project Start Date: Jan 1, 2011
• Project End Date: Dec 31, 2014
• Grant Year: 2011
• Program Code: [A1411]- Foundational Program: Agricultural Water Science

Project Director
Nielsen-Gammon, J.

Recipient Organization
TEXAS A&M UNIVERSITY
750 AGRONOMY RD STE 2701
COLLEGE STATION,TX 77843-0001

Performing Department
Atmospheric Sciences

Non Technical Summary
For drought triggers and decision-making, there is an unmet need for drought assessment information at the local (sub-county) scale. A daily precipitation analysis produced by the National Weather Service could potentially serve as input to a drought trigger tool, but the analysis includes long-term biases due to radar calibration and other issues that detrimentally affect the estimates of drought severity. This project will develop a reliable technique for calibrating the daily precipitation analysis to minimize biases in estimates of accumulated precipitation, perform a statistical analysis of the historical precipitation record so that the precipitation analyses can be converted to drought index information, create a web-based delivery system for the drought index information so that the products can be tested and evaluated in different parts of the United States, and estimate the effectiveness and benefit of the drought index information. The project, a collaboration between investigators at Texas A&M University, North Carolina State University, and Purdue University, will lay the ground work for nationwide drought monitoring at the local scale. The long-range benefit to agriculture of this project will be to improve the resiliency of agriculture through more accurate drought response decisions and more precise identification and relief for agricultural producers suffering under drought. These drought tools will enable location-specific decision-making designed to reduce the risk of loss or of more serious water restrictions at a later date.

Animal Health Component

100%

Research Effort Categories

Basic

(N/A)

Applied

100%

Developmental

(N/A)

Classification

Knowledge Area (KA)	Subject of Investigation (SOI)	Field of Science (FOS)	Percent
132	0430	2070	100%

Knowledge Area
132 - Weather and Climate;

Subject Of Investigation
0430 - Climate;

Field Of Science
2070 - Meteorology and climatology;

Keywords

drought

planning

drought trigger

precipitation

multisensor precipitation estimate

statistics

drought index

standardized precipitation index

radar bias correction

decision-making

Goals / Objectives
Rainfall data is particularly important for drought assessment and trigger development. Real-time tools for observing and quantitatively estimating precipitation are undergoing rapid improvement and have far outpaced the ability of traditional drought indices to provide temporally and spatially resolved drought information for trigger purposes. If the high-resolution precipitation information currently available can be transformed into a set of drought trigger tools, the benefits would extend across the entire range of the user community. The goal of this project is to develop techniques and tools that provide drought trigger information in the spatial context needed by individual agricultural producers and water users, water supply managers, and drought relief agencies. The specific objectives of this project are: 1) develop a reliable technique for calibrating analyses based on Multisensor Precipitation Estimation (MPE) to minimize accumulated precipitation biases; 2) develop the historical probability distribution function (PDF) for key drought indices from long-term climate stations and apply them to the finescale precipitation analyses to create spatially-resolved index values suitable for drought trigger use; 3) create a web-based delivery system for the spatially-resolved indices for testing and evaluation purposes in three key representative states; and 4) estimate the effectiveness and benefit of the delivered spatially-resolved index values through interaction with users of drought triggers. The outcomes of this project will be: 1) a tested, validated, and implemented method for correcting the MPE analyses for long-term biases due to known sources of bias in radars; 2) a regularly-produced, bias-corrected, freely-available, high-resolution accumulated precipitation analysis that will be suitable for incorporation into other third-party drought analysis tools such as land-surface models and integrated remote sensing tools; 3) a regional frequency analysis with a drought focus spanning most of the conterminous United States; 4) a web site and a web-based tool serving high-resolution drought index information, available initially for Texas, North Carolina, and Indiana on a trial basis, but expanded for regional and national users as the products mature; 5) a refinement of the trigger tools and web-based display and access to make them more user-friendly; 6) a better understanding of how end users evaluate and utilize objective drought trigger information.

Project Methods
In this project, we will develop and implement a calibration for the accumulated precipitation based on comparison with monthly rain gauge data. First, taking advantage of the radar intercomparisons available along lines equidistant from two radars, we will estimate the magnitude of radar calibration biases using monthly accumulations of precipitation. Second, the range-dependent radar bias will be estimated from computing the azimuthal average radar-estimated accumulated precipitation and comparing the resulting precipitation as a function of radial distance from the radar with the radial dependence of radar-gauge differences. The radial dependence will be specified using a multiparameter curve such as a quadratic. The absolute accuracy of these techniques will be estimated by withholding gauge information from specific radar domains and estimating the systematic and range-dependent biases using values from surrounding radars. The drought index tool requires period-of-record statistical precipitation information from long-term rain gauge observations for the computation of SPI and other precipitation-based indices. We will analyze the rain gauge data for the central and eastern United States using an L-moments approach described by Hosking and Wallis. For mean precipitation, we will use the PRISM gridded normals for 1971-2000. A variety of indices, including the most familiar ones such as the SPI and the PDSI, will be computed from the input information on a daily basis and posted on web sites that already serve climate information to the user community for Texas, North Carolina, and Indiana. Documentation will be provided to the broad user community, to the media, and, via training and workshops, to water supply decision-makers, extension educators, and other key stakeholder representatives. In turn, the workshops will guide improvements in accessibility, display, and usefulness of the drought products. Educational materials, including handouts, posters, newsletters items, and even content for a newly created comic book will be developed to provide access for an informal audience to the broader drought issues and more specifically to the use of our products as a drought trigger and analysis tool. A combination of diagnostic assessments and assessments based on network analysis will be undertaken with the objective of understanding the utility of our products and the improvements needed before making it operational potentially through the US Drought Monitor and the NSF DRINet project. Through our own comparisons with existing drought tools and outreach and discussion with agricultural producers and water supply managers, we will investigate the value of the drought indices as early warning systems and decision aids. We will identify the most valuable specific drought indices according to time of year and nature of agriculture (key commodity types and presence or absence of irrigation) and provide science-based guidance for the use of the tools based on comparison with crop health and water supply restrictions.

Progress 01/01/11 to 12/31/14

Outputs
Target Audience: The target audiences include fellow climate scientists, meteorologists, water resource managers, Drought Monitor authors, Water Shortage Task Force members, extension educators, crop advisors, graduate and undergraduate students, and the general public. Changes/Problems: Nothing Reported What opportunities for training and professional development has the project provided? The drought trigger tool products are an integral part of nearly every outreach presentation made by the Texas State Climatologist on drought and climate within the state of Texas. During the course of the project, over 200 such presentations have been made. These presentations include continuing education and professional development programs for farmers, ranchers, and water supply managers. The project activities were used for training and professional development of faculty, professional staff, graduate and undergraduate students, postdoctoral researchers, and extension educators. Not all of those benefitting were supported by the grant but they benefited in terms of the scientific and interdisciplinary work that the grant provided to take ideas to the practitioners. Five PhD students are using parts of the project in their dissertations. One related to the assessment of drought characterization across Midwest and for assessing impacts on corn production. While other is understanding the coupled interaction between soil moisture, rainfall, and regional predictability, and other student is reviewing the impacts on the soil moisture and high resolution drought changes in the corn Belt. Undergraduate students worked in using the project to provide input to the media and extension educators via weekly updates about Indiana climate and weather updates that were used in assessing changes in the evapotranspiration and high resolution drought changes. Manuscripts, dissertation chapters, and curriculum material all have been effectively used the project datasets and provided training and professional development opportunities at Purdue University and the Indiana State Climate Office. This project provided funding support for one graduate student and two manuscripts are expected to come out of her thesis. "Development of a High Resolution Standardized Precipitation Index for the Contiguous US" will describe the SPI calculation methodology and sensitivity testing to input datasets; "Case Study Evaluations of a High Resolution SPI" will provide an assessment of the high-resolution SPI's utility in drought monitoring though comparisons to independently-generated SPIs and the USDM in two case studies: the 2012 central Great Plains drought and the 2007-2008 Carolinas drought. The manuscripts will be submitted to the AMS Journal of Applied Meteorology and Climatology in 2015 for review. How have the results been disseminated to communities of interest? Presentations and results from the data analysis were made to extension educators through workshops, and teleconference on crop status and through media releases. Manuscripts were communicated to conferences and to peer reviewed journals. The data products were integrated on the Indiana and Texas State Climate Office webpages and as part of their drought tools. Presentations and demonstrations of the data and web services was given at the 2013 and 2014 annual meetings of the American Association of State Climatologists (AASC). AASC members represent a core audience of contributors to the US Drought Monitor and support state levels services for USDA, including FSA, NRCS, and Cooperative Extension. Documentation has been written on the project background, methodology, and how to use the web services. Additionally, detailed documentation has been provided on how to customize the web services to meet specific user needs and how to embed the drought content developed within other pages. An example of this at work can be found on the Office of the Texas State Climatologist's drought website:http://atmo.tamu.edu/osc/drought/ and on the Midwestern Regional Climate Center's website: http://mrcc.isws.illinois.edu/cliwatch/drought/droughtTriggerTool.jsp. The website has also been shared with US Drought Monitor authors via email. Maps are incorporated into the suite of products used for guidance in creation of the US Drought Monitor, providing regular evaluation of their performance. What do you plan to do during the next reporting period to accomplish the goals? Nothing Reported

Impacts
What was accomplished under these goals? A beta version of a comprehensive MPE calibration system has been developed. The system consists of three parts: a beam blockage filling algorithm, a range-dependent bias correction algorithm, and a two-dimensional kriging algorithm. The last part is not novel, but its application after the preceding steps is novel. Each step takes advantage of the varying signal-to-noise ratio at different precipitation accumulation periods. The range-dependent bias correction algorithm is the heart of the system and is innovative in that it uses both gauge-radar comparisons and pure precipitation estimates in its identification of rangedependent biases. The beta-version system has not yet been implemented in real-time; we are refining the algorithm under NOAA support and are preparing journal articles describing the procedures. The existing version is now widely accepted as a measure of drought severity, with allowance made for locations at which a large discrepancy exists between precipitation analyses and rain gauge values. The Texas products serve as the starting point for recommendations to the US Drought Monitor for drought intensity within the state of Texas, and other states are beginning to provide Drought Monitor input on the basis of the drought trigger products displayed by NCSU. A website for viewing high-resolution SPI maps for the contiguous US was developed in 2012 for testing and was shared with a larger user community in 2013 and 2014 (www.nc-climate.ncsu.edu/drought). Gridded SPI maps are calculated following logic developed by McRoberts and Nielsen-Gammon (2012). In addition to SPI, Percent of Normal Precipitation and Total Precipitation are calculated and updated daily for a range of timescales (1, 2, 3, 4, 5, 6, 7, 8, 9, 12, 15, 18, 24, and 36 months). Grids are stored on a THREDDS server, where the data can be accessed via a variety of methods, including OPeNDAP, NetCDF subset service, and Web Map Service (http://convection.meas.ncsu.edu:8080/thredds/catalog/sco/spi/catalog.html ). The website for viewing the SPI grids was developed with personalization in mind and many user-selected options, such as location, zoom, and time scale can be entered into the URL string and bookmarked. Users can download grids as geotiffs projected in geographic coordinates, click points on the map to obtain the SPI value, and view map animations. Additionally, users can click a point on the map to view the time series of SPI, Percent of Normal, or Accumulated Precipitation for the given point. Links to download the time series data or a static image are also provided. Like the map interface, the time series webpage can be tailored to the user's specific interests and bookmarked. www.nc-climate.ncsu.edu/drought_timeseries Purdue University accomplishments: The high resolution drought trigger tools and products were communicated widely to the agronomic and the broader extension and outreach community. Discussions about the subcounty scale variability and the impact of drought on corn yield and drought stress was made part of planning process to be communicated to the broader community. Classroom activities and curriculum material for undergraduate and graduate courses relating the drought tools and case studies to understand droughts. Assessment of drought impacts on the corn yield and the characterization of the 2012 drought in Midwest US Assessment of drought trigger tools for coupled hydroclimatic applications in diagnostic and predictive mode. Integration of the project based products into advisories and outlooks being provided to the wider agronomic and water community in Indiana. Development of a FAQ and summary on droughts and its variability to be used by the extension educators Modeling and data analysis studies to understand the relation between rainfall, soil moisture and evapotranspiration changes, and drought changes

Publications

• Type: Journal Articles Status: Published Year Published: 2014 Citation: O. Kellner, and D. Niyogi, 2014, Assessing Drought Vulnerability in Agricultural Production Systems In the Context of the 2012 Drought. Journal of Animal Science, 92 (7), 2811-2822
• Type: Journal Articles Status: Published Year Published: 2014 Citation: Mallick, K., Jarvis, A. J., Boegh, E., Fisher, J. B., Drewry, D. T., Tu, K. P., ... & Niyogi, D. (2014). A Surface Temperature Initiated Closure (STIC) for surface energy balance fluxes. Remote Sensing of Environment, 141, 243-261.
• Type: Journal Articles Status: Accepted Year Published: 2015 Citation: Kellner, Olivia, and D. Niyogi, 2015: Climate variability and the U.S. Corn Belt: ENSO and AO phase-dependent hydroclimatic feedbacks to corn production at regional and local scales. Conditionally Accepted and in revision, Earth Interactions. 2015.
• Type: Journal Articles Status: Submitted Year Published: 2015 Citation: Kellner, Olivia, D. Niyogi, and F.D. Marks, 2015: Land-falling Tropical System Contribution to the hydroclimate of the Eastern U.S. Corn Belt. Wea. and Cli. Extremes, Submitted February 2015.
• Type: Journal Articles Status: Under Review Year Published: 2015 Citation: Niyogi, D., X. Liu, J. Andresen, Y. Song, A. Jain, O. Kellner, E.S. Takle, and O.C. Doering, 2015: Crop models can capture the impacts of climate variability on corn yield. Geophys. Res. Lett., Submitted Nov. 2014, revision submitted March 2015.
• Type: Journal Articles Status: Under Review Year Published: 2015 Citation: Xing, L., J. Andresen, H. Yang, and D. Niyogi, 2015: Calibration and validation of the Hybrid- Maize crop model for regional analysis and application over the US Corn Belt, Earth Interactions, revision in review.
• Type: Book Chapters Status: Published Year Published: 2014 Citation: O. Kellner and D. Niyogi, 2014: Agroclimatology. Encyclopedia of Natural Resources: Air. Doi: 10.1081-ENRA-120047622 .
• Type: Conference Papers and Presentations Status: Other Year Published: 2014 Citation: Liu, X., L.L. Biehl, E. Karlsson, A. Kumar, D. Niyogi. A land data assimilation system (LDAS) based dataset for regional agro-climatic assessments over the U.S. Corn Belt. American Meteorological Societys 21st Conference on Applied Climatology, Boulder, CO, June 2014. Oral presentation.
• Type: Conference Papers and Presentations Status: Other Year Published: 2014 Citation: Karlsson, E. and X. Liu. A land data assimilation system (LDAS) based dataset for regional hydroclimatic assessments over the U.S. Corn Belt. Office of Interdisciplinary Graduate Programs Spring Reception, West Lafayette, IN, Apr. 2014. Poster presentation.
• Type: Theses/Dissertations Status: Published Year Published: 2015 Citation: Kellner, Olivia, 2015, A Hydroclimatic Assessment of the U.S. Corn Belt across Spatial and Temporal Scales, Ph. D. Dissertation, Purdue University.
• Type: Theses/Dissertations Status: Published Year Published: 2014 Citation: McRoberts, D. B., December 2014: Minimizing Biases in Radar Precipitation Estimates. Ph.D. Dissertation, Texas A&M University
• Type: Journal Articles Status: Published Year Published: 2015 Citation: Zheng, Y., A. Kumar, D. Niyogi, 2015, Impacts of landatmosphere coupling on regional rainfall and convection, Climate Dynamics, 44, 2383  2409.

Progress 01/01/14 to 12/31/14

Outputs
Target Audience: The target audiences include fellow climate scientists, meteorologists, water resource managers, Drought Monitor authors, Water Shortage Task Force members, extension educators, crop advisors, graduate and undergraduate students, and the general public. Changes/Problems: Nothing Reported What opportunities for training and professional development has the project provided? Undergraduates and graduate students majoring in Agronomy and Atmospheric Sciences worked on the project related activities and had the opportunity to participate in this issue based research problem. Course materials were prepared for broader use in the class room and which can also be used for training and professional development. How have the results been disseminated to communities of interest? The HIRDTT is generated in real time independently by Texas A&M University (for Texas) and by North Carolina State University (for the eastern 2/3 of the United States). The trigger products are publicly available to all users through user interfaces developed by the two institutions. The NCSU website was presented at the 2014 American Association of State Climatologists annual meeting. A document describing the target audiences and how to use the page has been added to the website. The page has also been added to the Midwestern Regional Climate Center's website, including their Midwest Climate Watch, which was highlighted in their newsletter (http://mrcc.isws.illinois.edu/cliwatch/eNews/observer_201503_full.html). The grids have also been incorporated into weekly calls with the NC Drought Management Advisory council and as routine input into the US Drought Monitor. Project activities were discussed and communicated via media interactions and Purdue AgAnswers. Study results were presented at conferences and workshops both nationally and internationally. Study findings and research results were documented in peer reviewed journal articles. What do you plan to do during the next reporting period to accomplish the goals? Although the project has officially ended, several journal articles are in preparation that will disseminate the results of this project and acknowledge support.

Impacts
What was accomplished under these goals? A beta version of a comprehensive MPE calibration system has been developed. The system consists of three parts: a beam blockage filling algorithm, a range-dependent bias correction algorithm, and a two-dimensional kriging algorithm. The last part is not novel, but its application after the preceding steps is novel. Each step takes advantage of the varying signal-to-noise ratio at different precipitation accumulation periods. The range-dependent bias correction algorithm is the heart of the system and is innovative in that it uses both gauge-radar comparisons and pure precipitation estimates in its identification of range-dependent biases. The beta-version system has not yet been implemented in real-time; we are refining the algorithm under NOAA support and are preparing journal articles describing the procedures. On the NCSU product delivery web site, animations of gridded drought indicators for a user-defined area, period, and interval were added. Additionally, maintenance to the website and gridded data server were performed to ensure continued services beyond this project. Accomplishments at Purdue University: Continued close working partnerships with water shortage task force, county extension educators, media, and the agronomic community regarding the use of drought triggers and drought tools for subcounty scale assessments. Integration of drought information within undergraduate and graduate class room curriculum material for agronomy students. This includes both refinement of the teaching material and case studies. Presentations and demonstrations of the products and tools to the visitors and extension educators as well as media/outreach community through the Indiana State Climate Office. Integration of the high resolution drought trigger into understanding of the impact on corn yields across the US Corn Belt.

Publications

• Type: Journal Articles Status: Published Year Published: 2014 Citation: O. Kellner, and D. Niyogi, 2014, Assessing Drought Vulnerability in Agricultural Production Systems In the Context of the 2012 Drought. Journal of Animal Science, 92 (7), 2811-2822
• Type: Journal Articles Status: Published Year Published: 2014 Citation: Mallick, K., Jarvis, A. J., Boegh, E., Fisher, J. B., Drewry, D. T., Tu, K. P., ... & Niyogi, D. (2014). A Surface Temperature Initiated Closure (STIC) for surface energy balance fluxes. Remote Sensing of Environment, 141, 243-261.
• Type: Journal Articles Status: Accepted Year Published: 2015 Citation: Kellner, Olivia, and D. Niyogi, 2015: Climate variability and the U.S. Corn Belt: ENSO and AO phase-dependent hydroclimatic feedbacks to corn production at regional and local scales. Conditionally Accepted and in revision, Earth Interactions. 2015.
• Type: Journal Articles Status: Submitted Year Published: 2015 Citation: Kellner, Olivia, D. Niyogi, and F.D. Marks, 2015: Land-falling Tropical System Contribution to the hydroclimate of the Eastern U.S. Corn Belt. Wea. and Cli. Extremes, Submitted February 2015.
• Type: Journal Articles Status: Under Review Year Published: 2015 Citation: Niyogi, D., X. Liu, J. Andresen, Y. Song, A. Jain, O. Kellner, E.S. Takle, and O.C. Doering, 2015: Crop models can capture the impacts of climate variability on corn yield. Geophys. Res. Lett., Submitted Nov. 2014, revision submitted March 2015.
• Type: Journal Articles Status: Under Review Year Published: 2015 Citation: Xing, L., J. Andresen, H. Yang, and D. Niyogi, 2015: Calibration and validation of the Hybrid- Maize crop model for regional analysis and application over the US Corn Belt, Earth Interactions, revision in review.
• Type: Book Chapters Status: Published Year Published: 2014 Citation: O. Kellner and D. Niyogi, 2014: Agroclimatology. Encyclopedia of Natural Resources: Air. Doi: 10.1081-ENRA-120047622 .
• Type: Journal Articles Status: Published Year Published: 2015 Citation: Zheng, Y., A. Kumar, D. Niyogi, 2015, Impacts of landatmosphere coupling on regional rainfall and convection, Climate Dynamics, 44, 2383  2409.
• Type: Conference Papers and Presentations Status: Other Year Published: 2014 Citation: Liu, X., L.L. Biehl, E. Karlsson, A. Kumar, D. Niyogi. A land data assimilation system (LDAS) based dataset for regional agro-climatic assessments over the U.S. Corn Belt. American Meteorological Societys 21st Conference on Applied Climatology, Boulder, CO, June 2014. Oral presentation.
• Type: Conference Papers and Presentations Status: Other Year Published: 2014 Citation: Karlsson, E. and X. Liu. A land data assimilation system (LDAS) based dataset for regional hydroclimatic assessments over the U.S. Corn Belt. Office of Interdisciplinary Graduate Programs Spring Reception, West Lafayette, IN, Apr. 2014. Poster presentation.
• Type: Theses/Dissertations Status: Published Year Published: 2015 Citation: Kellner, Olivia, 2015, A Hydroclimatic Assessment of the U.S. Corn Belt across Spatial and Temporal Scales, Ph. D. Dissertation, Purdue University.
• Type: Theses/Dissertations Status: Published Year Published: 2014 Citation: McRoberts, D. B., December 2014: Minimizing Biases in Radar Precipitation Estimates. Ph.D. Dissertation, Texas A&M University

Progress 01/01/13 to 12/31/13

Outputs
Target Audience: Drought Monitor authors, County Extension Educators, Extension Specialists, Crop Advisors and Crop Consultants, Drought and Water Shortage Task Force, Media, Students, Peer Scientific community, decision makers, NRCS, Forecasters, Ag economists, State Climatologists, General Public. Changes/Problems: Nothing Reported What opportunities for training and professional development has the project provided? Training and professional development continues for the graduate students, undergraduate, and post-doc involved with the project. How have the results been disseminated to communities of interest? As discussed above, the primary means of disseminating the trigger tool is via the web. Awareness of the existence and utility of this tool has been increased through news releases, outreach fact sheets, community meetings, informal round table discussions and meetings with users. What do you plan to do during the next reporting period to accomplish the goals? Next year we will complete the project. We will implement bias correction, and continue spreading the word and soliciting feedback among agricultural users. The web site will be made more user-friendly and intuitive. This includes tweaks to the menus and language as well as adding more documentation, in the form of text or factsheets, about the methods used to calculate the maps as well as how to interpret them. Additionally, animations of maps for a user-defined area, period, and interval will be added. Once these changes have been implemented, a tutorial video will be made to help visitors navigate the website.

Impacts
What was accomplished under these goals? Techniques for bias correction remain under development. The PDF analysis has been completed for the United States. The web-based delivery system went live in 2013. Itremains operational, and improvements are ongoing. A demonstration of the website was given at the annual meeting of the American Association of State Climatologists (AASC) in early July 2013. Feedback from this group was incorporated prior to sharing it with a wider audience via an email to the AASC listserv in late July, 2013. Included in this email was documentation on how to use the website, how to customize it to meet specific user needs, and how to iframe the site within other pages. An example of this at work can be found on the Office of the Texas State Climatologist’s drought website:http://atmo.tamu.edu/osc/drought/. The documentation provided to users is also available on the website and is updated whenever revisions are made. Major efforts have been devoted to user interaction and feedback, through the following mechanisms: News releases (as needed) community meetings (typically once a month) Round table discussions ( typically once a week during growing season; monthly otherwise) Class material for undergraduate and graduate class (one per semester) Fact sheets for extension educators and broader outreach Feedback to US drought monitor Collation of statewide conditions and guidance using project tools and other data resources for assessing drought conditions Review of the drought tools and their usability by conducting informal meetings and discussions with users The website was also shared with US Drought Monitor authors via email, and this led to a brief collaborative effort to write scripts to download GIS-ready maps on a weekly basis directly from the THREDDS server where they are housed. Maps continue to be downloaded weekly and are incorporated into the suite of products used for guidance in creation of the US Drought Monitor, providing regular evaluation of their performance. Subsequent conversations since sharing the website suggest that a variety of users have successfully used this page and continue to do so.

Publications

• Type: Journal Articles Status: Published Year Published: 2013 Citation: Mallick, K., Jarvis, A., Fisher, J. B., Tu, K. P., Boegh, E., & Niyogi, D. (2013). Latent Heat Flux and Canopy Conductance Based on Penman-Monteith, Priestley-Taylor Equation, and Bouchet's Complementary Hypothesis. Journal Of Hydrometeorology, 14(2), 419-442. doi:10.1175/JHM-D-12-0117.1
• Type: Journal Articles Status: Published Year Published: 2013 Citation: Mallya, G., L. Zhao, X. C. Song, D.Niyogi, R.S. Govindaraju, 2013: 2012 Midwest drought in the United States, Journal of Hydrologic Engineering, 18, 737-745
• Type: Journal Articles Status: Awaiting Publication Year Published: 2014 Citation: Mallick, K., Jarvis, A. J., Boegh, E., Fisher, J. B., Drewry, D. T., Tu, K. P., ... & Niyogi, D. (2014). A Surface Temperature Initiated Closure (STIC) for surface energy balance fluxes. Remote Sensing of Environment
• Type: Journal Articles Status: Under Review Year Published: 2014 Citation: O. Kellner, and D. Niyogi, Assessing Drought Vulnerability in Agricultural Production Systems In the Context of the 2012 Drought. Journal of Animal Science
• Type: Book Chapters Status: Accepted Year Published: 2014 Citation: D. Niyogi, and O. Kellner, 2013: Agroclimatology. Encyclopedia of Natural Resources, Taylor and Francis Group, Encyclopedias Online.

Progress 01/01/12 to 12/31/12

Outputs
OUTPUTS: Our prototype drought trigger tool for Texas continues to serve as a real-time point of dissemination for Texas drought monitoring information. The product archive now extends back by more than five years. The web site includes drought index maps as well as drought index change maps. Impacts from this web site are described below. A new website for viewing high resolution SPI maps for the contiguous US has been developed. Gridded SPI maps are calculated following logic developed by McRoberts and Nielsen-Gammon (2011) and using two different MPE datasets: NWS and NCEP. In addition to SPI, Percent of Normal Precipitation and Total Precipitation were calculated using each MPE dataset. Daily maps are available for a range of lags (1, 2, 3, 4, 5, 6, 7, 8, 9, 12, 15, 18, 24, and 36 months) and from start dates of 2002-02-01 for products calculated using NCEP MPE data and from 2005-02-01 for products calculated using NWS MPE data. All maps are pre-generated with new maps created daily, allowing the page to load quickly. The website has also been developed with personalization in mind and many user-selected options, such as location, zoom, and lag can be entered into the URL string and bookmarked. The website is http://www.nc-climate.ncsu.edu/drought An additional feature is time series calculation for a single grid point. A user can click on the map to place a marker; clicking on the marker produces a link to obtain a time series that is generated on-the-fly for the given point. Users can toggle between viewing time series for SPI, Percent of Normal Precipitation, and Accumulated Precipitation as well as click links to download the time series data or a static image. This website allows users to view the evolution of drought, as measured by SPI, for their specific location as well as observe differences in SPI calculated using each MPE dataset. Like the map interface, the time series webpage can be tailored to the users specific interests and bookmarked. This web site is http://www.nc-climate.ncsu.edu/drought_timeseries and it is accessed from the drought map web site. The products have shown at numerous seminars throughout the state of Texas and the national products have been presented at the 2012 meeting of the American Association of State Climatologists. PARTICIPANTS: John W. Nielsen-Gammon (Texas A&M University). Principal Investigator. Oversaw project and participated in research to improve radar bias correction of rainfall estimates. D. Brent McRoberts (Texas A&M University). Graduate student. Manages Texas drought image generation and dissemination, lead researcher for bias correction of rainfall estimates. Ryan Boyles (North Carolina State University). Co-Principal Investigator. Oversaw project to develop a nation-wide drought index display and dissemination tool. Rebecca Cumbie (North Carolina State University). Graduate student. Lead developer of tools for manipulation and display of drought index maps and time series. Dev Niyogi (Purdue University). Co-Principal Investigator. Developing contacts and planning workshops on the use of the drought trigger tool. TARGET AUDIENCES: Presently the products still require expert interpretation. Thus the primary target audience at the present time consists of drought experts such as the US Drought Monitor authors, who generate the weekly drought depictions. They have developed an appropriate amount of trust in the drought index products. A secondary audience consists of Texas stakeholders, such as members of the Texas legislature, who have a need to know about current drought conditions, and they have gained an appreciation for the large spatial variability of drought and rainfall. PROJECT MODIFICATIONS: Nothing significant to report during this reporting period.

Impacts
The Texas products are now widely accepted as a measure of drought severity, with allowance made for locations at which a large discrepancy exists between precipitation analyses and rain gauge values. The Texas products serve as the starting point for recommendations to the US Drought Monitor for drought intensity within the state of Texas. National scale outcomes/impacts are on hold until we unveil the final bias-corrected version of our national drought index products.

Publications

• Nielsen-Gammon, J. W. 2012. The 2011 Texas drought. Texas Water Journal, 3(1), 59-95.

Progress 01/01/11 to 12/31/11

Outputs
OUTPUTS: During the reporting period, we have produced prototype drought monitoring maps for Texas on a regular weekly basis. These products have been disseminated to the general public through our web site at http://atmo.tamu.edu/osc. During the reporting period, we have given frequent outreach talks throughout Texas to drought-sensitive agricultural interests. These talks have utilized the drought monitoring maps that we have been producing. Relevant outreach talks were given at: Late Season Pecan Management Seminar, Texas AgriLife Extension, Comanche, TX. Central Texas Cow/Calf Clinic, Texas AgriLife Extension, Lampasas, TX. Buyers Salebration Trade Show, Nitro-Phos Fertilizers and Horticultural Distributors, Houston, TX. 2011 Beef Financial Management Conference, Frost PLLC, Amarillo, TX. Palo Pinto County Beef Cattle Program, Texas AgriLife Extension, Palo Pinto, TX. Texas Water Symposium, 2011 Session One, Junction, TX. Tri-County Beef and Forage Workshop, Texas AgriLife Extension, Corrigan, TX. Annual Meeting, American Society of Agricultural Consultants, San Antonio, TX. Texas Commodity Symposium, Amarillo, TX. Texas Turfgrass Conference, Texas Turfgrass Association, San Antonio, TX. The drought monitoring maps formed a major part of my official status report on the Texas drought, provided to the Texas Legislature on October 31, 2011: The 2011 Texas Drought. The status report is available at http://atmo.tamu.edu/osc/library/osc_pubs/2011_drought.pdf and has been submitted to the Texas Water Journal for publication. In addition to the above, we gave two formal scientific presentations on the use of our drought monitoring tools: Nielsen-Gammon, J. W., 2011: The land that drought forgot. US Drought Monitor Workshop, USDA/NOAA, Fairfax, VA. McRoberts, D. B., and J. W. Nielsen-Gammon, 2011: Modified standardized precipitation index for integrated drought comparison. 19th Conference on Applied Climatology, American Meteorological Society, Asheville, NC. PARTICIPANTS: John Nielsen-Gammon: PI/PD. Supervised progress of the project, supervised project personnel at Texas A&M University, coordinated activities among partner organizations, provided quality control for drought products, served as primary point of interaction with the U.S. Drought Monitor, served as primary outreach person for product dissemination within Texas. D. Brent McRoberts: Graduate student. Provided weekly generation of drought products, rewrote, documented, and automated drought product generation, began development of bias correction algorithms. North Carolina State University: Began development work to integrate drought products into suite of web-GIS products for the eastern United States. Purdue University: Initiated contacts with extension and other personnel in preparation for workshops on using and improving the new regional drought maps when they become available. TARGET AUDIENCES: Nothing significant to report during this reporting period. PROJECT MODIFICATIONS: Nothing significant to report during this reporting period.

Impacts
We have completely revised and documented the software used for generating the maps. This revision has made the map generation faster and more robust, improving the reliability of the drought maps. The regular availability of the maps, combined with the increasing familiarity with the maps among the drought community, has led to increasing reliance upon the drought maps in construction of the US Drought Monitor. The US Drought Monitor is able to depict drought in Texas with much higher spatial specificity than before, with the result that the drought relief programs administered by the USDA are able to provide more accurate relief.

Publications

• No publications reported this period