Geophysics and climate research: High resolution 2‐D seismic surveys recorded at Lake Tana, Ethiopia — the source of the Blue Nile

Understanding the complex relationships between rainfall and runoff processes is necessary for the proper estimation of the quantity of runoff generated in a watershed. The surface runoff was simulated using the Hydrologic Modelling System (HEC-HMS) for the Gilgel Abay Catchment (1609 km2), Upper Blue Nile Basin, Ethiopia. The catchment was delineated and its properties were extracted from a 30 m × 30 m Digital Elevation Model (DEM) of the Lake Tana Basin. The meteorological model was developed within HEC-HMS from rainfall data and the control specifications defined the period and time step of the simulation run. To account for the loss, runoff estimation, and flow routing, Soil Conservation Service Curve Number (SCS-CN), Soil Conservation Service Unit Hydrograph (SCS-UH) and Muskingum methods were used respectively. The rainfall-runoff simulation was conducted using six extreme daily time series events. Initial results showed that there is a clear difference between the observed and simulated peak flows and the total volume. Thereafter, a model calibration with an optimization method and sensitivity analysis was carried out. The result of the sensitivity analysis showed that the curve number is the sensitive parameter. In addition, the model validation results showed a reasonable difference in peak flow (Relative Error in peak, REP = 1.49%) and total volume (Relative Error in volume, REV = 2.38%). The comparison of the observed and simulated hydrographs and the model performance (NSE = 0.884) and their correlation (R2 = 0.925) showed that the model is appropriate for hydrological simulations in the Gilgel Abay Catchment.

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Lake Tana and the Blue Nile

International Affairs ◽

10.1093/ia/15.3.471a ◽

1936 ◽

Keyword(s):

Lake Tana ◽

Blue Nile

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General discussion

Philosophical Transactions of the Royal Society of London. Series A, Mathematical and Physical Sciences ◽

10.1098/rsta.1983.0050 ◽

1983 ◽

Vol 309 (1508) ◽

pp. 397-397

Keyword(s):

Remote Sensing ◽

High Resolution ◽

Electrical Engineering ◽

Research Programme ◽

Scientific Committee ◽

Climate Research ◽

Maximum Benefit ◽

The World ◽

Scientific Return ◽

Ocean Studies

E. D. R. Shearman (Department of Electronic and Electrical Engineering, University of Birmingham, U.K.). We have had comments from a number of speakers on three planned remote-sensing satellites designed for ocean studies, the European ERS-1, the Canadian Radarsat and the Japanese satellite ERTS-1, all scheduled for 1988-90. If the orbits were coordinated, one suggested revisit interval, namely 3 days, for high-resolution observations could be reduced to a 1-day revisit interval. Could anyone tell us whether an attempt is being made internationally to agree on a single revisit cycle and to coordinate the launches so that the maximum benefit is obtained from the overall effort? J. T. Houghton, F.R.S. The various space agencies involved are discussing questions of coordination. Further, the Joint Scientific Committee of the World Climate Research Programme is organizing meetings to try to ensure the best possible scientific return from the various ocean observation satellites that will be flying at the time mentioned.

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Late Pleistocene desiccation of Lake Tana, source of the Blue Nile

Quaternary Science Reviews ◽

10.1016/j.quascirev.2006.11.020 ◽

2007 ◽

Vol 26 (3-4) ◽

pp. 287-299 ◽

Cited By ~ 96

Author(s):

Henry F. Lamb ◽

C. Richard Bates ◽

Paul V. Coombes ◽

Michael H. Marshall ◽

Mohammed Umer ◽

...

Keyword(s):

Late Pleistocene ◽

Lake Tana ◽

Blue Nile

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Water balance of Lake Tana and its sensitivity to fluctuations in rainfall, Blue Nile basin, Ethiopia

Journal of Hydrology ◽

10.1016/j.jhydrol.2005.05.011 ◽

2006 ◽

Vol 316 (1-4) ◽

pp. 233-247 ◽

Cited By ~ 177

Author(s):

S. Kebede ◽

Y. Travi ◽

T. Alemayehu ◽

V. Marc

Keyword(s):

Water Balance ◽

Nile Basin ◽

Lake Tana ◽

Blue Nile ◽

Blue Nile Basin

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The WegenerNet 3D weather and climate research facility: A unique open-air laboratory for high-resolution precipitation studies

10.5194/egusphere-egu2020-1417 ◽

2020 ◽

Author(s):

Jürgen Fuchsberger ◽

Gottfried Kirchengast ◽

Christoph Bichler

Keyword(s):

High Resolution ◽

Precipitable Water ◽

Heavy Precipitation ◽

Satellite System ◽

Doppler Velocity ◽

Time Sampling ◽

Volume Data ◽

Station Network ◽

Climate Research ◽

Weather And Climate

The WegenerNet Feldbach Region is a unique weather and climate observation facility comprising 155 meteorological stations measuring temperature, humidity, precipitation, and other parameters, in a tightly spaced grid within a core area of 22 km &#215; 16 km centered near the city of Feldbach (46.93&#176;N, 15.90&#176;E). With its stations every about two square-km (area of about 300 square-km in total), and each station with 5-min time sampling, the network provides regular measurements since January 2007. In 2020, the station network will be expanded by three major new components, converting it from a 2D ground station network into a 3D open-air laboratory for weather and climate research at very high resolution. The following new observing components will start operations by spring 2020:<ol><li>A polarimetric X-band Doppler weather radar for studying precipitation parame- ters in the troposphere above the ground network, such as rain rate, hydrometeor classification, Doppler velocity, and approximate drop size and number. It can provide 3D volume data (at about 1 km &#215; 1 km horizontal and 500 m vertical res- olution, and 5-min time sampling) for moderate to strong precipitation. Together with the dense ground network this allows detailed studies of heavy precipitation events at high accuracy.</li> <li>An azimuth-steerable microwave/IR radiometer for vertical profiling of temperature, humidity, and cloud liquid water in the troposphere (with 200 m to 1 km vertical resolution, and 5-min time sampling), also capable of measuring integrated water vapor (IWV) along line-of-sight paths towards Global Navigation Satellite System (GNSS) satellites.</li> <li>A water vapor mapping high-resolution GNSS station network, named GNSS StarNet, comprising six ground stations, spatially forming two star-shaped subnets (one with &#8764;10 km interstation distance, and one embedded with &#8764;5 km distance), for providing slant IWV, vertical IWV, and precipitable water, among other parame- ters, at 5-min time sampling.</li> </ol>We will present a detailed overview of the new components, their location, specifica- tion, and output data products.

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