Title: Importance of HydroMeteorological Data Bank for Use in Coupled Models and Disaster Management Using
1Importance of Hydro-Meteorological Data Bank for
Use in Coupled Models and Disaster Management
Using New Techniques (RS/GIS) in Turkey
Prof. Dr. A. Ünal SORMAN Middle East Technical
University (METU) Department of Civil
Engineering 22 25 May 2004
2Introduction
- Speech can be divided into 5 main topics
- A. Importance of snow and data collection
- B. Hydrological models and coupling with
atmospheric circulation models - C. Flood forecasting from early snowmelt/rainfall
in 2004 (a case study in Turkey) - D. Scaling and meteorological data assimilation
- E. Future research activities for operational
runoff forecast -
3A. Importance of Snow and Data Collection
- Snow is an important resource of water
- Determination of SWE is important to forecast
the volume of spring melt
- Ground truth is the main data source in
investigating the snow covered areas - Reflectance values from the snow surface should
be watched during the snow melt period
4Snow studies between 1964-2002
- Snow observations
- Classical methods (snow sticks, snow tubes)
5Recent Studies by DSI and DMI
- In TEFER project, 206 automated meteorological
stations are under construction - 3 radar stations are to be operated in western
regions of Turkey
6Snow studies between 1964-2002
- 2. Snow research and modeling in basin scale
- Basin wide snow studies were initiated by METU,
Tübitak-Bilten, EIE, DSI and DMI under a
protocol sponsored by NATO in 1997.
7Snow in Eastern Turkey
- Snowmelt runoff constitutes approximately 60-70
of yearly total volume in Euphrates (Firat)
River, where major dams are located in series
(Keban, Karakaya, Atatürk, Birecik and Karkamis). - Therefore forecasting the snow potential in
advance could result in better management of the
countrys water resources.
8Automated Snow Meteorological (Snow-Met)
Stations
Because of high snow potential, Karasu Basin in
the Upper Euphrates is selected as a pilot basin
for snow studies
9Station Locations in Karasu Basin
10Station Instrumentation
11Güzelyayla Snow-Met Station
Elev 2065 m Lat 40o1219 Long
41o2818
Sensors
Rain Gauge
Snow pillow
Snow Lysimeter
12Güzelyayla Snow-Met Station Sensors
Ultra Sonic Depth Sensor
Temperature and Relative Humidity Sensor
Inmarsat Antenna
Wind Speed and Direction Sensor
Solar Radiation Sensor
Net Radiometer
13Güzelyayla Snow-Met StationSnow Pillow
3 meter Diameter Hyphalon Snow Pillow
14Güzelyayla Snow-Met StationSnow Lysimeter
- Snow Lysimeter measures the
- amount
- rate
- duration
- of snow melt
15Snow-Met StationCommunication
Satellite
- Data from snow-met stations are downloaded via
satellite or GSM where available.
METU Office
Snow-met Station
16Snow-Met Station Processed Data
Lysimeter
Snow Depth
Snow Water Equivalent
Snow data, 2003 water year
17Snow Studies Concentrate on
- Snow cover area monitoring SCA
- Snow water equivalent analysis SWE
- Snow albedo measurements - Albedo
18Snow Cover Area (SCA)
- National Oceanic and Atmospheric Administration
(NOAA) - Temporal Resolution 2 or 3 times a day
- Spatial Resolution 1.1 km
- Supervised Classification
- Unsupervised Classification
- Threshold (Theta Algorithm)
19Snow Cover Area (SCA)
13 April 1998 Geocoded NOAA Image
20Snow Cover Area (SCA)
- Special Sensor Microwave/Imager (SSM/I)
- Temporal Resolution 1 or 2 times a day
- Spatial Resolution 30 km
Modified Grody/Basist Algorithm, 3 April 1997
21Snow Cover Area (SCA)
- Moderate Resolution Imaging Spectroradiometer
(MODIS) - Temporal Resolution 1 or 2 times a day
- Spatial Resolution 0.5 km
5 April 2004
22Snow Cover Area (SCA)
13 April 1997
Supervised Class. 13 April 1997
Snow Covered Area
23Snow Water Equivalent (SWE)
- Snow Water Equivalent is the actual amount of
water stored in the basin which will turn into
runoff once snow melt occurs.
24Snow Water Equivalent (SWE)
- Snow pillows are used to measure continuous SWE
at a point - SWE data are randomly checked by snow tube
measurements done by state organizations near
snow-met stations
Station SWE, 2003 Water Year
25Snow Albedo
- Albedo is a very critical parameter in snow as
it determines the amount of absorbed solar energy
(major energy for snowmelt) for melting process
to take place, Energy Budget. - Dry fresh snow albedo 0.80-0.90
- Wet dirty snow albedo 0.20-0.30
Snow albedo is a function of snow grain size,
depth, age, impurities
Albedometer present at Güzelyayla and Ovacik
Snow-met stations
26Snow Albedo
Daily average snow albedo, 2004 water year
27Snow Albedo
MODIS Albedo
- Daily and 16-day albedo values from MODIS
Aqua/Terra satellite are analyzed
- Snow albedo variation is significant especially
during snow ablation stage. Therefore, temporal
variation as well as spatial variation is
important - Snow albedo is used in energy balance models and
modified temperature index models in hydrologic
modeling
28B1. Hydrological Models
- SRM (Snowmelt Runoff Model)
- Switzerland-USA, Temperature Index Model
- HBV (Hydrologiska By-rans avdeling for
Vattenbalans) - Sweden-Norway, Temperature Index Model
- SNOBAL (Snow Balance)
- USA, Point Two Layer Energy Balance
29Hydrologic Models (SRM)
- Parameters
- Snow runoff coef. (cSn)
- Rain runoff coef. (cRn)
- Degree day factor (a)
- Temp. lapse rate (?)
- Critic temperature (Tcrit)
- Rainy area (RCA)
- Recession coefficient (k)
- Time lag
- Variables
- Snow Covered Area (S)
- Temperature (T)
- Precipitation (P)
30Hydrologic Models (HBV)
- Model Structure
- Snow routine
- Critical Temp, Degree day, Rain/Snow correction
coeff. - Soil Moisture
- Field Capacity, Pot. Evap.
- Upper Zone
- Quick recession coeff.
- Lower Zone
- Slow recession coeff., Percolation
31Hydrologic Models (SNOBAL)
- ?Q Rnet H LE G M
-
- ?Q net energy change in snowpack (W/m2)
- Rnet net radiation (W/m2)
- H sensible heat flux (W/m2)
- LE latent heat flux (W/m2)
- G ground heat (W/m2)
- M advection (W/m2)
32Near Real Time Forecasts
NOAA (optic)
SSM/I (passive mw)
MODIS (optic)
Web site
Modem-Satellite Phone
METU
cd/ftp
Hydrologic models
DSI
Runoff Stations
GSM
ftp
ECMWF
DMI
MM5
33GRIB format Grided Binary
Boundary Conditions
ECMWF (40x40km)
Remote Sensing NOAA/AVHRR MODIS
GIS
High spatial elevation model
MM5 (9x9km) 1.2GB
Snow Covered Area
Basin Characteristics
NCAR Non hydro static Atm. Model
Grid Distributed SCA P/ T
Forecasted Grid Data
Format Conversion
Hydrological Models
Model Variables (Temp., Prec.)
Forecasted Runoff
Model Parameters
Integration of Real Time Atmospheric and
Hydrological Models for Runoff Forecasts in Turkey
34Results Conclusions from hydrological model
studies
- Formation of a common digital data banks
- Format conventions and parameter selections
- Enabling research oriented data sharing
- Installation of new hydro meteorological stations
and quality increment by optimization - Use of RS and GIS in basin model studies. Related
software, hardware and satellite selection.
35Results Conclusions from hydrological model
studies
- Simulation and forecast studies by
- Lumped/Distributed (full/semi) models in
- daily, monthly and yearly basis
- Providing the cooperation between universities
and governmental organizations - Selection of projects having national priorities
36B2. Atmospheric Hydrological Model Coupling
Elements of Hydrologic Cycle State and Diagnostic
Parameters (Snow water equivalent, depth, snow
surface temperature, Elements of net energy, melt
speed, Stream flow, etc.)
37Model Input Flow
- Grid
- Atmospheric Weather Prediction
- (Analysis or Forecast)
- NOAA / AVHRR Images
- (1100 m resolution)
- (Snow covered area, cloud, land)
- MODIS Images
- (500 m Resolution)
- (Snow covered area, albedo)
Geophysical Maps (Digital elevation Model, Land
use, soil type, vegetal cover)
Physical Downscaling
- Point
- Meteorologic observations
- Hydrometric flow observations
Quality Check
Hydrological Model
38 Model Integration and Outputs
Air temperature Precipitation (rain/snow) Wind Hum
idity Air Pressure Cloud
Atmospheric Model (Forecast/Analysis)
Forecast / Analysis data
Integration
Snow water equivalent Snow depth Snow covered
area Snow temperature Melt rate Flow Energy flux
Hydrological Model (Operational / Research)
State and Diagnostic Data
39Physical Downscaling of Thermodynamic Variables
Thermodynamic Variables (Pressure, Temperature,
Humudity)
DEM Elevation greater than Model elevation?
Yes
No
Extrapolate temperature and virtual Temperature
to DEM elevation Compute pressure via
hydrostatic relation
Interpolate pressure, temperature and virtual
temperature to DEM elevation
Derive relative humudity from temperature
and pressure
40ECMWF DEM Turkey
41MM5 DEM Turkey
42MM5 Land Use Map
43ECMWF Temperature (3 May 2004)
44MM5 Temperature (3 May 2004)
45(No Transcript)
46Read Interpolate Plot (RIP) Air Temperature (3
May 2004)
47Read Interpolate Plot (RIP) Precipitation (3 May
2004)
48C. Analysis of the early 2004 flood event
- An unexpected snowmelt event has occurred during
late February and early March of 2004 in the
eastern and southern parts of Turkey - An analysis of the flood event is simulated using
1 day weather forecast data in a hydrological
model to forecast runoff in Upper Karasu Basin
(Kirkgöze Basin), where real time ground data
(snow, meteorological, stream flow) are collected
49Hydrological Runoff Forecasting
- HBV Model (Temperature Index Model)
- Input data into HBV model from global weather
forecasts (ECMWF) - Daily total precipitation
- Daily average air temperature
- Forecast simulations during the period of
- 28 February - 7 March 2004 in Kirkgöze Basin
50Global Weather Forecasts - ECMWF
Daily Total Precipitation (mm) of 5 May 2004
Air Temperature (oC) of 5 May 2004 1200
51Hydrological Model (HBV) Runoff Forecast
Observed and calculated runoff hydrographs at
Kirkgöze Basin outlet, DSI 21-01
52Hydrological Model Forecast Results
- R2, Nash efficiency criterion, is used in HBV
model to show the goodness of fit of the observed
and calculated values (from -? to 1.0, the
higher the value the better the model fit). - where observed runoff,
average runoff, calculated runoff -
- Normal values during HBV model calibrations are
within the range 0.5-0.9. For this analysis, R2
is 0.64.
53D. Data Assimilation and Downscaling
- Data collection, analysis and storage
- Quality control
- Physical downscaling of numerical weather
prediction (ECMWF and/or MM5) model outputs - Real time forecasting of stream flow with
hydrological models - Comparison of model outputs with observations
- Data assimilation and renew
54Users DSI, DMI EIE, KHGM Ministry of Env. and
Forest
Tools Satellites Aircrafts Balloons Meteorolo
gical Weather Stations
Products Snow covered area Snow depth Snow
water equivalent Snow surface temperature Precip
itation Soil moisture
55Downscaling
40 km
1 km
56Temperature and Precipitation Biases
57E. Future research activities for operational
runoff forecast
- Develop/validate hydrological models and coupled
model sub-components. Improve precipitation
(snow/rain) and runoff processes related to
spring snow accumulation/melt - Conduct experiments to understand the effects of
terrain data (DEM, land use, soil moisture,
vegetation)
58- Evaluate the effects of coupled model resolution
on seasonal and diurnal land-surface atmosphere
interactions in complex terrain regions. - Develop techniques for assimilating new Remote
Sensing products for MODIS / LANDSAT - Develop and understand cold season precipitation
including snow and frozen-ground
59- Investigate the effects of climate change
senarios for mid and long term - Assess and improve runoff models in coupled form
to validate streamflow estimates to be used by
managers / decision makers - Decrease the effects of flood and drought with
water resources planning strategies
60THANK YOU