Palaeoenvironmental reconstruction in the Sahara Desert

The Sahara Desert is the largest desert in the world (somewhere between 7 to 9 million km²), about one third of the African continent. It plays an important part in the global climate system, with a persistent high pressure zone over Libya which keeps the core desert hyper-arid (just a few mm/yr, with rainstorms occurring only once every ten or twenty years), and, as the satellite image above shows, it is a major source of atmospheric dust.

Edeyen Ubari (Photograph by Nick Brooks, UEA).

My research in the Sahara focuses on contemporary environmental processes and environmental change, making use of the synoptic overview provided by optical and radar remote sensing techniques to collect data for this vast, inaccessible area.

The above images show the oasis of Ubari and the edge of the Edeyen Ubari (Ubari Sand Sea), Top image is a Landsat Thematic Mapper false colour composite, middle image is from the JERS Synthetic Aperture Radar, bottom image is from the Radarsat Synthetic Aperture Radar. The bright reflecters evident among the dunes in the radar images are palaeolakes.

Palaeolake sediments in the Edeyen Ubari.

Analysis of these palaeolake sediments provides useful palaeoenvironmental data, and a way of dating past wet climate phases.

Cross sections through palaeolake sediments (Picture by Sue MacLaren, University of Leicester)

Reconstruction of Lake PalaeoFezzan, superimposed on 3D map, viewed from northwest.

A summary of Holocene climate history  in the Libyan Fezzan from palaeolake sediments, evaporites and organic deposits (diagram from Nick Drake, KCL)

For more information, see the Fezzan project website.

Or the Megafezzan website

Or see the following references:

Mattingly, D.J., al-Mashai, M., Aburgheba, H., Balcombe, P., Eastaugh, E., Gillings, M., Leone, A., McLaren, S., Owen, P., Pelling, R., Reynolds, T., Stirling, L., Thomas, D., Watson, D., Wilson, A.I. and White, K.  1998  The Fezzan Project 1998: preliminary report on the second season of work. Libyan Studies, 29, pp. 115-144.

Mattingly, D.J., al-Mashai, M., Balcombe, P., Drake, N.A., Knight, S., MacLaren, S., Pelling, R., Reynolds, T., Thomas, D., Wilson, A.I. and White, K.  1999  The Fezzan Project 1999: preliminary report on the third season of work. Libyan Studies, 30, pp. 129-145.

White, K., McLaren, S.J., Black, S. and Parker, A.  2000  Evaporite minerals and organic horizons in sedimentary sequences in the Libyan Fezzan: Implications for Palaeoenvironmental reconstruction. In McLaren, S.J. and Kniveton, D.R. (Eds.) Linking Climate Change to Land Surface Change, Amsterdam: Kluwer, pp. 193-208.

Mattingly, D.J., Al-Mashai, M., Balcombe, P., Barnett, T., Brooks, N.P.J., Cole, F., Dore, J., Drake, N.A., Edwards, D., Hawthorne, J., Helm, R., Leone, A., McLaren, S.J., Pelling, R., Preston, J., Reynolds, T., Townsend, A., Wilson, A.I. and White, K.  2000  The Fezzan Project 2000: Preliminary report on the fourth season of work. Libyan Studies, 31, pp. 103-120.

Brooks, N.P.J., White, K., Warr, B., Drake, N.A., McLaren, S.J.  2000  Remote Sensing for Dryland Geoarchaeological Investigations in Southern Libya: Preliminary Findings from the Fezzan Project. Adding Value to Remotely Sensed Data, Proceedings of the 26^th Annual Conference of the Remote Sensing Society, 12-14 September 2000, University of Leicester, 17pp., ISBN 0 946226 30 X

Mattingly, D.J., Brooks, N., Cole, F., Dore, J., Drake, N., Leone, A., Hay, S., McLaren, S., Newson, P., Parton, H., Pelling, R., Preston, J., Reynolds, T., Schrüfer-Kolb, I., Thomas, D., Tindall, A., Townsend, A. and White, K.  2001  The Fezzan Project 2001: Preliminary report on the fifth season of work. Libyan Studies, 32, pp. 133-153.

Brooks, N.P.J., White, K., Drake, N. and MacLaren, S.  2001  Changes in vegetative cover in the Wadi al-Ajal, southern Libya, over the past half-century. Geomatics, Earth Observation and the Information Society, Proceedings of the First Annual Conference of the Remote Sensing & Photogrammetry Society, 12-14 September 2001, University of London, pp. 247‑259, ISBN 0 946226 31 8

White, K., Brooks, N.P.J., Drake, N.A. and McLaren, S.J.  2003  Studies in Geography, Geomorphology, Environment and Climate. Chapter 2 in Mattingly, D.J. (Ed.) The Archaeology of Fazzan, Volume 1, Synthesis. London: The Society for Libyan Studies/Tripoli: The Department of Antiquities, pp. 37-74.

White, K., Brooks, N.P.J., Drake, N.A., Charlton, M. and MacLaren, S.J.  2003  Monitoring vegetation change in desert oases by remote sensing; a case study in the Libyan Fazzān. Libyan Studies, 34, pp. 153-166.

Drake, N.A., Wilson, A., Pelling, R., White, K., Mattingly, D.J. and Black, S.  2004  Water table decline, springline dessication and the early development of irrigated agriculture in the Wadi al-Ajal, Libyan Fazzan. Libyan Studies, 35, pp. 95-112.

White, K. and Mattingly, D.J.  2006  Ancient lakes of the Sahara. American Scientist, 94, pp. 58-65.

White, K., Charlton, M., Drake, N., McLaren, S., Mattingly, D. and Brooks, N. 2006  Lakes of the Edeyen Ubari and the Wadi al-Hayat. In Mattingly, D., McLaren, S., Savage, E., al-Fasatwi, Y. and Gadgood, K. (Eds.) The Libyan Desert, Natural Resources and Cultural Heritage, London: The Society for Libyan Studies, pp. 123-130.

Drake, N., White, K. and McLaren, S.  2006  Quaternary climate change in the Jarma region of Fazzan, Libya. In Mattingly, D., McLaren, S., Savage, E., al-Fasatwi, Y. and Gadgood, K. (Eds.) The Libyan Desert, Natural Resources and Cultural Heritage, London: The Society for Libyan Studies, pp. 133-144.

McLaren, S., Drake, N. and White, K.  2006  Late Quaternary environmental change in the Fazzan, Southern Libya: evidence from sediments and duricrusts. In Mattingly, D., McLaren, S., Savage, E., al-Fasatwi, Y. and Gadgood, K. (Eds.) The Libyan Desert, Natural Resources and Cultural Heritage, London: The Society for Libyan Studies, pp. 157-166.

Charlton, M.B. and White, K.  2006  Sensitivity of radar backscatter to desert surface roughness. International Journal of Remote Sensing,  27, pp. 1641-1659.

Armitage, S.J., Drake, N.A., Stokes, S., El-Hawat, A., Salem, M.J., White, K., Turner, P. and McLaren, S.J.  2007  Multiple phases of North African humidity recorded in lacustrine sediments from the Fazzan Basin, Libyan Sahara. Quaternary Geochronology, 2, pp. 181-186.

Mattingly, D., Lahr, M., Armitage, S., Barton, H., Dore, J., Drake, N.A., Foley, R., Merlo, S., Salem, M., Stock, J. and White, K.  2007, Desert migrations: people, environment and culture in the Libyan Sahara. Libyan Studies, 38, pp. 115-156.

Drake, N.A., El-Hawat, A.S., Turner, P., Armitage, S.J., Salem, M.J., White, K. and McLaren, S.  2008  Palaeohydrology of the Fazzan Basin and surrounding regions: the last 7 million years. Palaeogeography Palaeoclimatology Palaeoecology, 263, pp. 131-145, doi: 10.1016/j.palaeo.2008.02.005