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Session Goals

FAMINE EARLY WARNING SYSTEMS NETWORK Understanding Climatology in advance of Forecast Information 2014 FEWS NET Regional Training Meetings. Session Goals. Understand use of the terms climatology and variability Characterize an area using rainfall climatology

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Session Goals

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  1. FAMINE EARLY WARNING SYSTEMS NETWORKUnderstanding Climatology in advance of Forecast Information2014 FEWS NET Regional Training Meetings

  2. Session Goals • Understand use of the terms climatology and variability • Characterize an area using rainfall climatology • Combine time series, and variability to analyze implications in agriculture • Know how to use the climatology knowledge base for an area of concern to develop an assumption in advance of forecast information __________________________________________ FAMINE EARLY WARNING SYSTEMS NETWORK

  3. Steps to developing agroclimatology assumptions 1. Understand the climatology for the area of concern (well in advance of SOS and as necessary) 2. Evaluate current climate modes (~3 months before SOS and until EOS) 3. Interpret available forecasts (~2 months before SOS and through EOS) 4. Incorporate monitoring data from remote sensing and other sources (SOS through EOS) __________________________________________ FAMINE EARLY WARNING SYSTEMS NETWORK

  4. Defining climatology • Climate: how the atmosphere behaves over a long period of time; average weather over a long period of time • Weather: the conditions of the atmosphere over a short period of time. • Climatology: long term average of a weather variable. “Climate is what you expect , weather is what you get” __________________________________________ FAMINE EARLY WARNING SYSTEMS NETWORK

  5. Understanding Characteristics of an Area of Concern • Review seasonal calendar and understand seasonal context and patterns • Review the key aspects of climatology in your area of concern: • Spatial and temporal distribution of rains • Changes in temperature • Growing season (start and end) • Water requirements for staple crops • Winds • Understand elevation and other key parameters impacting agriculture in the area of concern __________________________________________ FAMINE EARLY WARNING SYSTEMS NETWORK

  6. Climate variability • Spatial variability: changes of a climate variable across a landscape Average rainfall, October to May. 1981-2012 __________________________________________ FAMINE EARLY WARNING SYSTEMS NETWORK

  7. Climate Variability • Temporal Variability: changes over time • intra-annual refers to changes within a season. • inter-annual refers to changes between years. __________________________________________ FAMINE EARLY WARNING SYSTEMS NETWORK

  8. Rainfall Data Sources • CHIRPS: USGS/UCSB-CHG, InfraRed unbiased by climatology, added stations. 1981-present, 5Km, global 50N-50S, 5 days total. • TRMM: NASA InfraRed, microwave, radar, stations data. 2000-present, 25Km, global 50N-50S,tmp 3hr. • RFE: NOAA CPC, InfraRed, microwave, GTS stations. 2001-present, 10Km, Africa, Central Asia, daily. • ARC2: NOAA CPC, InfraRed, GTS stations. 1982-present, 10Km, Africa, Central Asia, daily. __________________________________________ FAMINE EARLY WARNING SYSTEMS NETWORK

  9. Sources of Data and Tools to be Used • RFE Rainfall plots • CHIRPS • End of Season WRSI products __________________________________________ FAMINE EARLY WARNING SYSTEMS NETWORK

  10. Sources of data and tools to be used • Mapviewer (USGS) • RFE Rainfall plots __________________________________________ FAMINE EARLY WARNING SYSTEMS NETWORK

  11. Seasonal Average Rainfall Season: October to June Max dek: 40mm Cumulative rainfall 500mm __________________________________________ FAMINE EARLY WARNING SYSTEMS NETWORK

  12. Seasonal Average Rainfall Season: October to June Max dek: 70mm Cumulative rainfall 500mm __________________________________________ FAMINE EARLY WARNING SYSTEMS NETWORK

  13. Seasonal Average Rainfall Season: October to Jan and Mar – Jun. (bimodal) Max dek: 50mm Cumulative rainfall ~250mm for the first season __________________________________________ FAMINE EARLY WARNING SYSTEMS NETWORK

  14. Seasonal Average Rainfall Season: ? Max dek: ? Cumulative rainfall ? m __________________________________________ FAMINE EARLY WARNING SYSTEMS NETWORK

  15. Obtaining Data from Map Viewer __________________________________________ FAMINE EARLY WARNING SYSTEMS NETWORK

  16. Using CHIRPS data __________________________________________ FAMINE EARLY WARNING SYSTEMS NETWORK

  17. Temporal Variability The plot shows the in??? variability How do we measure variability? __________________________________________ FAMINE EARLY WARNING SYSTEMS NETWORK

  18. How do we measure variability? Standard Deviation: a measure of variation or how spread the data are Coefficient of variation is the ratio of the standard deviation to the mean CV= (std / mean) * 100 CV allows the comparison between different magnitudes of variation, even if they have different means. __________________________________________ FAMINE EARLY WARNING SYSTEMS NETWORK

  19. How do we measure variability? The time series plot is another way to show how variable rainfall has been through time. __________________________________________ FAMINE EARLY WARNING SYSTEMS NETWORK

  20. How do we measure variability? stdv CV Now who could tell us what these two maps mean? __________________________________________ FAMINE EARLY WARNING SYSTEMS NETWORK

  21. How do we measure variability? The cumulative rainfall plots is a way to show the inter-annual variability. The plots show that there more spread on the South African area than that of Angola __________________________________________ FAMINE EARLY WARNING SYSTEMS NETWORK

  22. Agriculture, water balance Water Requirement Satisfaction Index (WRSI) • Model to predict crop performance • Allows us to determine rainfall distribution over the season Water Depth ( mm) PET WR AET Senay 2003 SOS EOS LGP WRSI = AET / WR __________________________________________ FAMINE EARLY WARNING SYSTEMS NETWORK

  23. Rainfall Distribution, WRSI Timeseries The time series plot shows the end of season WRSI values for each year WRSI is an indicator of how well the rainfall total was distributed during the growing season __________________________________________ FAMINE EARLY WARNING SYSTEMS NETWORK

  24. Conclusion • Understanding the general patterns of rainfall, such as average seasonal totals, variability through time and distribution during the season, allow you to make initial assumptions about the season. __________________________________________ FAMINE EARLY WARNING SYSTEMS NETWORK

  25. InfraRed data A region of the electromagnetic spectrum that has slightly longer wavelengths and lower frequencies than visible light, but is not visible to the human eye. Infrared light can be detected as the heat from a fire or a light bulb. (back) __________________________________________ FAMINE EARLY WARNING SYSTEMS NETWORK

  26. Tropical Precipitation Measuring Mission, (TRMM) • PR- Precipitation Radar: • - 3-D maps of storm structure. • Intensity and distribution of the rain • Rain type, storm depth and height TMI – TRMM Microwave Imager: - Measures microwave energy emitted by the earth and the atmosphere to quantify water vapor, cloud water and rainfall intensity in the atmosphere. • VIRS – Visible and InfraRed Scanner: - senses radiation coming up from the Earth in five spectral regions, ranging from visible to infrared, • Ability to delineate rainfall. • serves as a transfer standard to other measurements made using POES or GOES LIS- Lighting and Imaging Sensor: detects and locates lightning over the tropical region of the globe. back Video http://pmm.nasa.gov/education/videos/trmm-15-reign-rain NASA http://pmm.nasa.gov/node/158

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