Water & Climate; Floods & Droughts (The yin & yang of water availablilty) Water & Climate; Floods & Droughts (The yin & yang of water availablilty)

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1 (Acknowledgment: This presentation was developed in collaboration with ESA, NEON and NCEAS, federal agencies and academic team members from minority serving institutions.) Water & Climate; Floods & Droughts (The yin & yang of water availablilty) Jack Hermance Brown University (Aug 20, 2009) Water & Climate; Floods & Droughts (The yin & yang of water availablilty) (Note: A number of the spatial datasets that are shown are accessible for hands-on GIS projects.) Jack Hermance Brown University (Aug 20, 2009) Modern Tools for Studying the Hydrologic Environment In the field (ground-truthing) From space From the air USGS, NSF, NOAA, NASA, USDA/USFS Objective: To Understand the Interactions Among the Hydrological/Ecological Elements accessible water atmospheric vapor groundwater precipitation rain/snow/hail surface water soils soil water landforms/ landscapes/land use vegetation groundcover/ forest/crops/grasslands topography elevation ocean currents deep water temperature profile ocean floor topography sea surface temperature coastal features coastline topology beach physiography/morphology wind patterns atmospheric pressure geology geomorphology physiography 1

2 Global Circulation of Water "Weather" has distinct sources, signatures and behaviors. Patterns of Weather Movement (A matter of scale.) The Sun is the ultimate source for the energetics of water movement. But it is the Earth's gravity, shape and motions that are responsible for the continual redistribution of water over the globe. Copyright 2009 Pearson Prentice Hall, Inc. 2

3 Here we see the effects of the sun's energy being redistributed (January). Here we see the effects of the sun's energy being redistributed (July). We want to understand the impact of these redistributions on water availability. Temperature: January Temperature: July Redistribution of the atmosphere (and water vapor). Redistribution of the atmosphere (and water vapor). Atmospheric Circulation: January Atmospheric Circulation: July 3

4 Redistribution of ocean currents. Physiography Ocean Circulation The interactions of solar radiation, the atmosphere (e.g. winds), ocean circulation and global weather systems with the Earth's physiography play a first-order role in the redistribution of water. Physiography It is often useful to classify landforms. We will be particularly interested in North America. Physiographic Classes 4

5 It is often useful to classify landforms. Physiographic Classes Physiographic Classes (And, of course, plains, hills and mountains, etc. have unique soils, plants and eco-systems that depend and interact with hydrology.) San Francisco Saint Louis Consider a physiographic profile transecting the Western United States. (Such a profile is readily constructed in ArcGIS.) 5

6 The topographic relief crossing the backbone of North America plays a fundamental role in the distribution and redistribution of water. (And can be exported to an Excel spreadsheet, etc., for further analysis,... but that's for another day.) (What is the geologic cause of this relief?) Major river basins are defined by surface topography. Physiography and climate variables determine regional precipitation. 6

7 Landcover, hydrography and political boundaries. Water Holding Capacity of Soils Jack Hermance September 03, 2009 Precipitation, physiography and climate are responsible for natural landcover. And all of these variates interact to govern available soil moisture and runoff to streams. Consider the St. Lawrence Watershed. Consider the St. Lawrence Watershed. Cornwall, Ont. Buffalo, NY An underpinning theme of this inquiry will be that the runoff from a catchment represents the sum total, composite quality of the eco-systems contained therein. Consider the mean river discharge at two gauges: Cornwall, Ont.; Buffalo, NY. 7

8 Water/Landscape Interactions at the Regional Scale Clearly imprinted on the runoff (stream discharge) data for this period of record are several major droughts in the Northeast US (and Southeast Canada). Discuss the metric used here, so that the data may be overlaid. (USGS Graphic) The Basic Idea: Bring these concepts down to the operational level at the regional/ local/township/hamlet/plot level. Water, after all, is a global resource "consumed" at the local level. (USGS Graphic) What will be the keystone focus of the course? (Let me know!) Instrumentation/Technology? Regional issues? India Louisiana California South Africa African Sahel Middle East Process oriented? Water and ecology Droughts Floods Wildfire Storms Hazard forecasting Water supply (reservoirs, wells, etc.) Issues of coastal water supplies 8

9 Image Credits to: U.S. Geological Survey U.S. Department of Agriculture Pearson/Prentice Hall Publishers (Particularly Tasa Graphics, Inc.) National Science Foundation NASA NOAA/NWS (& by the author) Jack Hermance Brown University (Aug 20, 2009) 9