Hydro-Meteorological Trends in the Upper Omo-Ghibe River Basin, Ethiopia
Abstract
:1. Introduction
2. Study Area and Data Sources
2.1. Study Area
2.2. Data Sources
3. Methodology
Detection of Change Points with Pettit Test
4. Results
4.1. Temperature
4.1.1. Temperature Trend Analysis
4.1.2. Detection of Change Points for Temperature Time Series
4.2. Rainfall
4.2.1. Annual Rainfall Trend
4.2.2. Seasonal Rainfall Trend
4.2.3. Monthly Rainfall Trends
4.2.4. Detection of Change Points for Annual Rainfall
4.2.5. Detection Change Points of Seasonal Rainfall
4.2.6. Detection Change Points of Monthly Rainfall
4.3. Streamflow
Detection of Change Points in Streamflow Time Series
4.4. Discussion
5. Conclusions
Author Contributions
Funding
Acknowledgments
Conflicts of Interest
References
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Stations | Mean Annual | Wet Season | Dry Season |
---|---|---|---|
Assendabo | 1995(+), 0.00 | 1987(+), 0.01 | 1992(+), 0.00 |
1987(−), 0.09 | 1982(−), 0.11 | 1988(−), 0.15 | |
1995(+), 0.00 | 1997(+), 0.05 | 1995(+), 0.00 | |
Bonga | 1985(+), 0.25 | 2000(+), 0.12 | 1987(+), 0.04 |
1996(−), 0.21 | 1996(−), 0.16 | 1997(−), 0.40 | |
1985(+), 0.11 | 1985(+), 0.30 | 1985(+), 0.07 | |
Hossana | 1999(−), 0.41 | 1986(+), 0.42 | 1996(−), 0.16 |
1988(−), 0.11 | 1986(−), 0.03 | 1991(−), 0.05 | |
1988(−), 0.70 | 1996(−), 0.67 | 1995(−), 0.54 | |
Jimma | 1994(+), 0.00 | 1993(+), 0.03 | 1989(+), 0.02 |
1994(+), 0.00 | 1997(+), 0.04 | 1998(+), 0.00 | |
1994(+), 0.00 | 1992(+), 0.05 | 1994(+), 0.00 | |
Sekoru | 1993(−), 0.16 | 1993(−), 0.22 | 1987(+), 0.15 |
1988(−), 0.16 | 1986(−), 0.53 | 1988(−), 0.25 | |
1993(−), 0.28 | 1996(−), 0.53 | 2002(+), 0.44 | |
Shebe | 1993(−), 0.06 | 1990(−), 0.61 | 1991(−), 0.32 |
2001(−), 0.07 | 2001(−), 0.41 | 2001(−), 0.08 | |
1999(−), 0.08 | 1993(-), 0.41 | 1993(−), 0.03 | |
Wolkite | 2002(+), 0.00 | 2002(+), 0.01 | 2000(+), 0.00 |
1999(+), 0.02 | 1997(+), 0.03 | 1999(+), 0.01 | |
1996(+), 0.00 | 2002(+), 0.01 | 1994(+), 0.00 | |
Wolita | 1991(+), 0.03 | 1999(+), 0.01 | 1999(+), 0.05 |
1987(+), 0.02 | 2002(+), 0.23 | 1994(+), 0.14 | |
1995(+), 0.07 | 2002(−), 0.40 | 1987(+), 0.03 |
Meteorological Station | Mean Annual Rainfall (mm/year) | CV (%) for Rainfall Data | CV (%) for Temp. Data | Mean Annual Temp. (°C) | Elevation (m.a.s.l) | % Rainfall Record | Missing Aver. Temp. Record |
---|---|---|---|---|---|---|---|
Assendabo | 1181 | 17.38 | 2.49 | 19.70 | 2400 | 0.28 | 1.6 |
Bele | 1730 | 29.38 | _ | _ | 1200 | 3.81 | _ |
Bonga | 1631 | 12.84 | 3.78 | 19.34 | 1650 | 3.65 | 3.06 |
Hossana | 1146 | 22.71 | 5.70 | 17.08 | 1200 | 4.01 | 2.86 |
Jimma | 1520 | 13.19 | 2.48 | 19.52 | 1725 | 0.01 | 0.02 |
Limugenet | 1759 | 15.53 | _ | _ | 1690 | 9.86 | _ |
Sekoru | 1390 | 12.17 | 4.50 | 19.61 | 2100 | 5.08 | 6.03 |
Shebe | 1550 | 18.65 | 4.18 | 19.12 | 1635 | 8.03 | 8.12 |
Wolita | 1251 | 28.35 | 2.02 | 19.08 | 1300 | 1.86 | 5.04 |
Woliso | 1241 | 12.09 | _ | _ | 2000 | 7.05 | _ |
Wolkite | 1277 | 27.30 | 5.47 | 20.31 | 1550 | 8.06 | 6.12 |
Stations | Mean Annual (mm) | CV % | Mann-Kendall “Z” Statistics and “p” Value in (Brackets) | ||
---|---|---|---|---|---|
Annual | Wet Season | Dry Season | |||
Assendabo | 1181 | 17.38 | 2.21 (0.01) | 2.29 (0.01) | 0.67 (0.25) |
Bele | 1730 | 29.38 | 1.21 (0.03) | 1.76 (0.04) | 0.16 (0.44) |
Bonga | 1631 | 12.84 | −0.79 (0.48) | 1.03 (0.20) | −1.42 (0.92) |
Hossana | 1146 | 22.71 | 0.87 (0.19) | 1.70 (0.04) | 0.00 (0.50) |
Jimma | 1520 | 13.19 | 1.03 (0.20) | 1.22 (0.11) | −0.67 (0.75) |
Limugenet | 1759 | 15.53 | −0.54 (0.74) | −0.14 (0.52) | −0.16 (0.56) |
Sekoru | 1390 | 12.17 | −1.97 (0.03) | −1.34 (0.71) | −0.22 (0.59) |
Shebe | 1550 | 18.65 | −1.98 (0.04) | −1.34 (0.90) | −1.99 (0.04) |
Wolita | 1251 | 28.35 | 1.26 (0.10) | 1.38 (0.08) | 1.21 (0.29) |
Woliso | 1241 | 12.09 | −0.51 (0.70) | −0.67 (0.75) | 0.55 (0.29) |
Wolkite | 1277 | 27.30 | −1.11 (0.87) | −1.15 (0.87) | −0.40 (0.65) |
River Name | Catchment Area (km2) | Mean Annual Stream Flow (m3/s) | CV (%) | Stream Location | Period of Records | % Age of Missing Value |
---|---|---|---|---|---|---|
Gilgel Gibe | 2966 | 39.49 | 27.17 | Assendabo | 1981–2008 | - |
Bidru Awana | 41 | 0.43 | 42 | Sekoru | 1981–2008 | - |
Gojeb | 3577 | 54.34 | 19.02 | Shebe | 1981–2008 | 0.5 |
Wabi | 1866 | 34.79 | 37.28 | Wolkite | 1981–2008 | 0.36 |
Great Gibe | 15,690 | 195.53 | 34.03 | Abelti | 1981–2008 | 0.48 |
Stream Flow Variables | Stations | ||||
---|---|---|---|---|---|
Assendabo | Sekoru | Shebe | Wolkite | Abelti | |
Mean annual | +1.74 (0.04) | −0.83 (0.81) | −0.20 (0.58) | −0.22 (0.59) | +0.83 (0.20) |
Wet season | +2.29 (0.01) | −0.63 (0.74) | −0.43 (0.67) | −0.12 (0.55) | +1.19 (0.12) |
Dry season | +0.63 (0.26) | −0.12 (0.45) | −1.70 (0.04) | −0.77 (0.78) | +1.11 (0.13) |
January | +2.92 (0.00) | +1.09 (0.14) | +1.86 (0.03) | +0.63 (0.26) | +2.88 (0.00) |
February | +3.08 (0.00) | +0.26 (0.60) | −2.29 (0.01) | −2.73 (0.00) | +3.04 (0.00) |
March | +1.90 (0.03) | −0.12 (0.55) | −2.57 (0.01) | +0.32 (0.38) | +3.00 (0.00) |
April | +2.17 (0.01) | +0.91 (0.18) | +1.13 (0.02) | +0.34 (0.37) | +2.73 (0.00) |
May | +2.29 (0.01) | −0.51 (0.70) | +0.63 (0.26) | +0.26 ((0.40) | +2.96 (0.00) |
June | +0.87 (0.19) | −1.01 (0.84) | +0.32 (0.38) | −0.43 (0.67) | +2.37 (0.01) |
July | +1.58 (0.06) | −0.65 (0.74) | −1.22 (0.89) | +0.20 (0.42) | +1.50 (0.07) |
August | +1.54 (0.94) | −1.28 (0.10) | −1.82 (0.03) | −0.04 (0.48) | +0.28 (0.61) |
September | +0.63 (0.26) | −1.13 (0.87) | −1.15 (0.87) | −0.97 (0.83) | +0.63 (0.26) |
October | +0.36 (0.36) | −0.08 (0.53) | +0.12 (0.45) | +0.16 (0.44) | +0.40 (0.35) |
November | +0.99 (0.16) | −1.32 (0.91) | +0.00 (0.50) | +1.09 (0.14) | +0.85 (0.20) |
December | +2.05 (0.98) | −0.43 (0.33) | −2.37 (0.01) | +0.18 (0.57) | +1.50 (0.93) |
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Jaweso, D.; Abate, B.; Bauwe, A.; Lennartz, B. Hydro-Meteorological Trends in the Upper Omo-Ghibe River Basin, Ethiopia. Water 2019, 11, 1951. https://doi.org/10.3390/w11091951
Jaweso D, Abate B, Bauwe A, Lennartz B. Hydro-Meteorological Trends in the Upper Omo-Ghibe River Basin, Ethiopia. Water. 2019; 11(9):1951. https://doi.org/10.3390/w11091951
Chicago/Turabian StyleJaweso, Dessalegn, Brook Abate, Andreas Bauwe, and Bernd Lennartz. 2019. "Hydro-Meteorological Trends in the Upper Omo-Ghibe River Basin, Ethiopia" Water 11, no. 9: 1951. https://doi.org/10.3390/w11091951