Page 151 - AJWEP-22-5

Climate trend and policy in Lake Tana Basin

Table 6. Seasonal station‑based spatial trends in air temperature (1981 – 2022)
Season Statistic Station
Debre Tabor Injibara Gondar Merawi Woreta Delgi Bahir Dar Dangla
Winter
Mean 18.18 16.89 19.47 18.89 20.89 20.78 19.00 22.4
MKT 0.243* 0.049 0.216* 0.177 0.278* 0.271* 0.1777 0.2846**
p 0.024 0.657 0.045 0.102 0.01 0.012 0.099 0.008
Sen’s slope 0.015 0.003 0.014 0.016 0.016 0.021 0.011 0.031
Spring
Mean 20.50 19.86 22.36 22.36 23.39 23.78 21.70 22.36
MKT 0.379*** 0.199*** 0.278* 0.285** 0.346** 0.329** 0.288** 0.285**
p 0 0.0654 0.01 0.008 0.001 0.002 0.007 0.008
Sen’s slope 0.034 0.020 0.028 0.031 0.032 0.033 0.028 0.031
Summer
Mean 17.68 16.19 18.51 18.13 19.81 19.08 17.8735 18.13
MKT 0.072 0.113 0.057 0.171 0.006 0.129 0.112 0.171
p 0.508 0.298 0.603 0.114 0.965 0.233 0.303 0.114
Sen’s slope 0.005 0.005 0.003 0.008 0 0.006 0.005 0.008
Autumn
Mean 17.09 15.89 18.21 17.98 20.28 19.51 17.59 17.98
MKT 0.35** 0.448*** 0.363** 0.409 0.359** 0.351** 0.384*** 0.408***
p 0.001 0.0000 0.001 0 0.001 0.001 0.0003 0.0001
Sen’s slope 0.021 0.014 0.022 0.015 0.018 0.016 0.017 0.015
Notes: *p<0.05; **p<0.01; ***p<0.001.
Abbreviation: MKT: Mann–Kendall trend.

45000
40000
Carbon content (Mt C/year) 30000
35000

25000
20000
15000
10000
5000
0 Carbon content Trendline
1970 1972 1974 1976 1978 1980 1982 1984 1986 1988 1990 1992 1994 1996 1998 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020 2022

Years
Figure 8. Trends of global CO emissions (1970 – 2022) based on the EDGAR Report 2023
2
remaining stations displayed non-significant upward season experienced a statistically significant warming
trends. During spring, there was a significant upward or upward trend across all stations.
trend for all stations (p<0.05), except the Injibara
station, which experienced a non-significant upward 3.3. Causes and trends of global carbon dioxide
trend. During summer, air temperatures exhibited non- emissions
significant upward trends at all stations. The autumn According to the EDGAR Report 2023, the major

Volume 22 Issue 5 (2025) 145 doi: 10.36922/AJWEP025190142