Engelstaedter,S., Tegen,I. and Washington,R.(2006):
North African dust emissions and transport. Earth-science
Reviews, 79, 73-100.
『北アフリカからの風塵の放出と輸送』
『Abstract
The need for a better understanding of the role of atmospheric
dust in the climate system and its impact on the environment has
led to research of the underlying causes of dust variability in
space and time in recent decades. North Africa is one of the largest
dust producing regions in the world with dust emissions being
highly variable on time scales ranging from diurnal to multiannual.
Changes in the dust loading are expected to have an impact on
regional and global climate, the biogeochemical cycle, and human
environments. The development of satellite derived products of
global dust distributions has improved our understanding of dust
source regions and transport pathways in the recent years. Dust
models are now capable of reproducing more realistic patterns
of dust distributions due to an improved parameterization of land
surface conditions. A recent field campaign has improved our understanding
of the natural environment and emission processes of the most
intense and persistent dust sources in the world, the Bodele(両方のeの頭に´) Depression in Chad. In situ measurements
of dust properties during air craft observations in and down wind
of source regions have led to new estimates of the radiative forcing
effects which are crucial in predicting future climate change.
With a focus on the North African desert regions, this paper provides
a review of the understanding of dust source regions, the variability
of dust emissions, climatic controls of dust entrainment and transport,
the role of human impact on dust emission, and recent developments
of global and regional dust models.
Keywords: dust aerosols; emission; atmospheric transport; dust
variability; North Africa; Sahel』
1. Introduction
2. Dust sources
2.1. Natural sources
2.2. Anthropogenically modified sources
3. Dust transport and its environmental impacts
4. Temporal variability
4.1. Diurnal cycle
4.2. Intraseasonal variability
4.3. Annual cycle
4.3.1. Impact of rainfall
4.3.2. Role of the atmospheric circulation
4.4. Interannual variability
4.5. Multiannual variability and trends
5. Dust properties and radiative effects
6. Modeling of North African dust
7. Summary
Acknowledgements
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