Mohammed Umer
Biographic Data
| ID | 177620 |
|---|---|
| NAME | Mohammed Umer |
| GIVEN NAMES | Mohammed |
| FAMILY NAME | Umer |
| SIGNATURE | UMER M |
| AFFILIATIONS | Addis Ababa University |
| ORCID | 0009-0004-5043-1658 |
| VERIFIED | Yes |
| TOTAL WORKS | 9 |
| TOTAL CITATIONS | 81 |
| AUTHOR COUNT | 9 |
| EDITOR COUNT | 0 |
| FIRST PUBLICATION YEAR | 2003 |
| LATEST PUBLICATION YEAR | 2015 |
| H-INDEX | 5 |
Social-ecological systems in the Anthropocene
Understanding social-ecological system dynamics is a major research priority for sustainable management of landscapes, ecosystems and resources. But the lack of multi-decadal records represents an important gap in information that hinders the development of the research agenda. Without improved information on the long-term and complex interactions between causal factors and responses, it will be difficult to answer key questions about trends, rat…
Continental-scale temperature variability during the past two millennia
Temperature variability over Africa during the last 2000 years
A growing number of proxy, historical and instrumental data sets are now available from continental Africa through which past variations in temperature can be assessed. This paper, co-authored by members of the PAGES Africa2k Working Group, synthesises published material to produce a record of temperature variability for Africa as a whole spanning the last 2000 years. The paper focuses on temperature variability during the ‘Medieval Climate Anoma…
Climatic change recorded in the sediments of the Chew Bahir basin, southern Ethiopia, during the last 45,000 years
Long-term resilience, bush encroachment patterns and local knowledge in a Northeast African savanna
Oxygen and carbon isotope composition of authigenic carbonate from an Ethiopian lake
The oxygen and carbon isotope composition of sedimentary carbonates formed in Lake Hayq, a closed-basin lake in northern Ethiopia, suggests marked variation in the balance between precipitation and evaporation during the last 2000 years. Diatom stratigraphy shows that the lake remained deep enough to support planktonic taxa, and was never saline. The record suggests that rainfall was higher than that of the twentieth century during most of this t…
Preliminary geology and paleontology of new hominid-bearing Pliocene localities in the central Afar region of Ethiopia
The Woranso-Mille paleontological study area is located in the central Afar region of Ethiopia, about 360 km northeast of the capital, Addis Ababa. Some parts of this area have been paleontologically known since the 1970s. However, most of the fossiliferous areas were discovered by surveys conducted in the region between 2002 and 2004. By the end of the 2006 field season, a total of 17 vertebrate localities had been designated, and more than 1000…
Holocene climate phases from buried soils in Tigray (northern Ethiopia)
Stratigraphic analysis of alluvial/colluvial sequences and 14 C dating have been used as proxies for Holocene climate changes in the highlands of Tigray (northern Ethiopia). The studied records show alternations of buried soils and peaty–clayey sediments, pointing to wet, stabilization phases, and organic-free colluvium layers resulting from the abrupt occurrence of dry-climate episodes. The 14 C dates, mostly unpublished, cluster in the 11,090–9…
Forest clearance and regrowth in northern Ethiopia during the last 3000 years
Pollen and charcoal analysis of sediment cores from two lakes in the highlands of northern Ethiopia provide evidence that the vegetation has changed in response to human impact during the last 3000 years. The natural, pre-disturbance vegetation of the area was Podocarpus-Juniperus forest. At about 500 bc, following Semitic immigration to northern Ethiopia, the forests were cleared and replaced by a secondary vegetation of Dodonaea scrub and grass…
Preliminary geology and paleontology of new hominid-bearing Pliocene localities in the central Afar region of Ethiopia
The Woranso-Mille paleontological study area is located in the central Afar region of Ethiopia, about 360 km northeast of the capital, Addis Ababa. Some parts of this area have been paleontologically known since the 1970s. However, most of the fossiliferous areas were discovered by surveys conducted in the region between 2002 and 2004. By the end of the 2006 field season, a total of 17 vertebrate localities had been designated, and more than 1000…
Social-ecological systems in the Anthropocene
Understanding social-ecological system dynamics is a major research priority for sustainable management of landscapes, ecosystems and resources. But the lack of multi-decadal records represents an important gap in information that hinders the development of the research agenda. Without improved information on the long-term and complex interactions between causal factors and responses, it will be difficult to answer key questions about trends, rat…
Temperature variability over Africa during the last 2000 years
A growing number of proxy, historical and instrumental data sets are now available from continental Africa through which past variations in temperature can be assessed. This paper, co-authored by members of the PAGES Africa2k Working Group, synthesises published material to produce a record of temperature variability for Africa as a whole spanning the last 2000 years. The paper focuses on temperature variability during the ‘Medieval Climate Anoma…
Forest clearance and regrowth in northern Ethiopia during the last 3000 years
Pollen and charcoal analysis of sediment cores from two lakes in the highlands of northern Ethiopia provide evidence that the vegetation has changed in response to human impact during the last 3000 years. The natural, pre-disturbance vegetation of the area was Podocarpus-Juniperus forest. At about 500 bc, following Semitic immigration to northern Ethiopia, the forests were cleared and replaced by a secondary vegetation of Dodonaea scrub and grass…
Oxygen and carbon isotope composition of authigenic carbonate from an Ethiopian lake
The oxygen and carbon isotope composition of sedimentary carbonates formed in Lake Hayq, a closed-basin lake in northern Ethiopia, suggests marked variation in the balance between precipitation and evaporation during the last 2000 years. Diatom stratigraphy shows that the lake remained deep enough to support planktonic taxa, and was never saline. The record suggests that rainfall was higher than that of the twentieth century during most of this t…
Long-term resilience, bush encroachment patterns and local knowledge in a Northeast African savanna
Holocene climate phases from buried soils in Tigray (northern Ethiopia)
Stratigraphic analysis of alluvial/colluvial sequences and 14 C dating have been used as proxies for Holocene climate changes in the highlands of Tigray (northern Ethiopia). The studied records show alternations of buried soils and peaty–clayey sediments, pointing to wet, stabilization phases, and organic-free colluvium layers resulting from the abrupt occurrence of dry-climate episodes. The 14 C dates, mostly unpublished, cluster in the 11,090–9…
Forest clearance and regrowth in northern Ethiopia during the last 3000 years
Pollen and charcoal analysis of sediment cores from two lakes in the highlands of northern Ethiopia provide evidence that the vegetation has changed in response to human impact during the last 3000 years. The natural, pre-disturbance vegetation of the area was Podocarpus-Juniperus forest. At about 500 bc, following Semitic immigration to northern Ethiopia, the forests were cleared and replaced by a secondary vegetation of Dodonaea scrub and grass…
Oxygen and carbon isotope composition of authigenic carbonate from an Ethiopian lake
The oxygen and carbon isotope composition of sedimentary carbonates formed in Lake Hayq, a closed-basin lake in northern Ethiopia, suggests marked variation in the balance between precipitation and evaporation during the last 2000 years. Diatom stratigraphy shows that the lake remained deep enough to support planktonic taxa, and was never saline. The record suggests that rainfall was higher than that of the twentieth century during most of this t…
Preliminary geology and paleontology of new hominid-bearing Pliocene localities in the central Afar region of Ethiopia
The Woranso-Mille paleontological study area is located in the central Afar region of Ethiopia, about 360 km northeast of the capital, Addis Ababa. Some parts of this area have been paleontologically known since the 1970s. However, most of the fossiliferous areas were discovered by surveys conducted in the region between 2002 and 2004. By the end of the 2006 field season, a total of 17 vertebrate localities had been designated, and more than 1000…
Long-term resilience, bush encroachment patterns and local knowledge in a Northeast African savanna
Climatic change recorded in the sediments of the Chew Bahir basin, southern Ethiopia, during the last 45,000 years
Continental-scale temperature variability during the past two millennia
Temperature variability over Africa during the last 2000 years
A growing number of proxy, historical and instrumental data sets are now available from continental Africa through which past variations in temperature can be assessed. This paper, co-authored by members of the PAGES Africa2k Working Group, synthesises published material to produce a record of temperature variability for Africa as a whole spanning the last 2000 years. The paper focuses on temperature variability during the ‘Medieval Climate Anoma…
Social-ecological systems in the Anthropocene
Understanding social-ecological system dynamics is a major research priority for sustainable management of landscapes, ecosystems and resources. But the lack of multi-decadal records represents an important gap in information that hinders the development of the research agenda. Without improved information on the long-term and complex interactions between causal factors and responses, it will be difficult to answer key questions about trends, rat…
Geography (9 works) · Climate change (6 works) · Geology and Paleoclimatology Research (6 works) · Archaeology (5 works) · Physical geography (5 works) · Geology (4 works) · Paleoclimatology (4 works) · Climatology (3 works) · Ecology (3 works) · Environmental Science (3 works)