Прикладная Гидрогеология Yoram Eckstein, Ph.D. Fulbright Professor 2013/2014 Tomsk Polytechnic University Tomsk, Russian Federation Spring Semester 2014 Useful links http://www.onlineconversion.com/ http://www.digitaldutch.com/unitconverter/ http://water.usgs.gov/ogw/basics.html http://water.usgs.gov/ogw/pubs.html http://ga.water.usgs.gov/edu/earthgwaquifer.html http://water.usgs.gov/ogw/techniques.html http://water.usgs.gov/ogw/CRT/ II. Hydrologic Cycle Qualitative Hydrologic Cycle Phase diagram of water The principle of mass conservation inflow = outflow ± change in storage Qin = Qout ± ΔS non-steady state or transient conditions if ΔS = 0 steady state conditions Fluxes in Global Hydrologic Cycle Storage in Global Hydrologic Cycle (in %) Inventory of the World's water reservoirs RESERVOIR Oceans Glaciers and Ice Sheets Ground-water Lakes Rivers Atmosphere Biosphere TOTAL VOLUME (cubic kilometres) PERCENTAGE OF TOTAL 1,370,000,000 97.25 29,000,000 2.05 9,565,000 0.685 125,000 0.01 1,700 0.0001 13,000 0.001 600 0.00001 1,408,705,300 100 Inventory of the World's water reservoirs Global values for the major fluxes between reservoirs. FLUX (cubic kilometres per year) RESERVOIRS PROCESS OCEANS-ATMOSPHERE Evaporation 400,000 Precipitation 370,000 Evaporation 60,000 Precipitation 90,000 Runoff 30,000 LAND MASSES ATMOSPHERE LAND MASSES - OCEANS Approximate residence time of water found in various reservoirs. Reservoir Approximate Residence Time Oceans 2500 years Lakes 100 years Shallow Ground-water 200 years Deep Ground-water 10,000 years Glaciers 40 years Seasonal Snow Cover 0.4 year Soil Moisture 0.2 year Atmosphere 8 days Rivers 16 days Approximate residence time of water in the Caspian Sea. Nubian Sandstone Aquifer the largest reservoir of “fossil” ground-water Nubian Sandstone Aquifer - the largest reservoir of “fossil” ground-water Nubian Sandstone Aquifer the largest reservoir of “fossil” ground-water Nubian Sandstone Aquifer the largest reservoir of “fossil” ground-water Evaporation http://www.whycos.org/hwrp/guide/chapt ers/english/original/WMO168_Ed2008_V ol_I_Ch4_Up2008_en.pdf http://nora.nerc.ac.uk/14359/1/wmoevap_ 271008.pdf Pan-Evaporation Pan evaporation is a measurement that combines or integrates the effects of several climate elements: temperature, humidity, rain fall, drought dispersion, solar radiation, and wind. Evaporation is greatest on hot, windy, dry, sunny days; and is greatly reduced when clouds block the sun and when air is cool, calm, and humid. Pan evaporation measurements enable farmers and ranchers to understand how much water their crops will need. Pan-Evaporation An evaporation pan is used to hold water during observations for the determination of the quantity of evaporation at a given location. Such pans are of varying sizes and shapes, the most commonly used being circular or square. The best known of the pans are the "Class A" evaporation pan and the "Sunken Colorado Pan". In Europe, India and South Africa, a Symon's Pan (or sometimes Symon's Tank) is used. Often the evaporation pans are automated with water level sensors and a small weather station is located nearby. Evapo-Transpiration Transpiration: The release of water from plant leaves Evapotranspiration is the sum of evaporation from the land surface plus transpiration from plants. Precipitation is the source of all water. Evapo-Transpiration Weighing lysimeters Evapo-Transpiration Precipitation Precipitation Methods of measurements dry precipitation Precipitation over a river basin What is the total volume of water that fell over the basin during the specified time period? cm/time Precipitation over a river drainage basin If the rain gauge network cm/time would be of uniform density i.e. each gauge would be representative of the same area, then a simple arithmetic average of point-rainfall data for each station would be sufficient to determine the effective uniform depth of precipitation over the drainage basin area. Precipitation over a river drainage basin Isohyetal method Isohyets – interpolated contour lines Precipitation over a river drainage basin Isohyetal method Effective uniform depth of precipitation = EUDP 𝒏 𝑬𝑼𝑫𝑷 = 𝑰𝒊 ∗ 𝑨𝒊 𝒊=𝟎 Precipitation over a river drainage basin Construction of Thiessen polygons (1) triangulation Precipitation over a river drainage basin Construction of Thiessen polygons (2) bisecting the laterals of each triangle Precipitation over a river drainage basin Construction of Thiessen polygons (3) Connecting the bisector into a network of polygons 𝒏 𝑬𝑼𝑫𝑷 = 𝑰𝒊 ∗ 𝑨𝒊 𝒊=𝟏 Reading assignment http://content.alterra.wur.nl/Internet/webdocs/ilripublicaties/publicaties/Pub162/pub162-h4.0.pdf Watershed = drainage basin Major drainage basin Sub-basin (minor drainage basin) Watershed = drainage basin Stream gauging 𝒏 𝑸= 𝒒𝒊 𝒊=𝟏 Effluent (or gaining) stream – typical in humid climate zones Perennial (effluent) stream hydrograph Influent (or losing) stream – typical in arid climate zones Ephemeral (influent) stream hydrograph Stream – gaining during rainy season (e.g., monsoon) and loosing during dry season Intermittent stream hydrograph Storm hydrograph components Storm hydrograph components Direct precipitation on the stream channel Storm hydrograph components Surface overland flow Storm hydrograph components Interflow and throughflow Storm hydrograph components Baseflow Baseflow recession on stream hydrograph Multi-year baseflow recession of one stream Q Qoe kt Multi-year baseflow recession of one stream Qot1 Vtp 2.3 Vtp – total potential ground-water discharge Qo – baseflow discharge rate at the beginning of recession t1 – time during which Qo0.1 Qo Multi-year baseflow recession of one stream Qot1 Vtp 2.3 Vtp – total potential ground-water discharge Qo – baseflow discharge rate at the beginning of recession t1 – time during which Qo0.1 Qo The volume of potential baseflow, Vt, remaining at some time , t, after the beginning of baseflow recession may be estimated by: Vt Vtp 10 t t 1 Multi-year baseflow recession of one stream The difference between the remaining potential ground-water discharge at the end of a given baseflow recession and the total potential ground-water discharge at the beginning of the next recession represents the recharge that takes place between the two recessions.