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A preliminary assessment on environmental vulnerability in Southern Africa
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8. Appendix 1: CLIMATE INFORMATION
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As taken from the web:
STATEMENT FROM THE FIFTH SOUTHERN AFRICA MIDSEASON CORRECTION FORECAST MEETING OF THE SOUTHERN AFRICA CLIMATE OUTLOOK FORUM
20-21 December 2001, Harare, Zimbabwe.
JANUARY TO MARCH 2002 SEASONAL RAINFALL OUTLOOK UPDATE
SUMMARY
Most of the Southern Africa Development Community (SADC) region will experience a largely normal to above-normal rainfall for the period January to March (JFM) 2002.
This Outlook is relevant only for seasonal time scales and relatively large areas. Local and month-to-month variations may occur. Any changes in the projected patterns of sea surface temperatures (SSTs) and other indicators over the next few weeks would affect the outlook in some areas. Updates of the outlooks therefore will be provided by the Drought Monitoring Centre, Harare (DMCH) and the National Meteorological Services (NMSs) in their respective countries.
The users are strongly advised to contact their NMSs for interpretation of this Outlook, finer details, updates and additional guidance.
THE CLIMATE OUTLOOK FORUM
From 20 to 21 December 2001, the Fifth Midseason Correction Forecast Meeting of the Southern Africa Climate Outlook Forum was convened in Harare, Zimbabwe by the DMCH in conjunction with the Department of the Meteorological Services of Zimbabwe to formulate consensus guidance projected for January to March 2002 rainfall for the SADC region. Users were active participants in the forum and raised issues pertaining to the interpretation and dissemination of the seasonal outlook.
METHODOLOGY
The Forum reviewed the state of the global ocean-atmosphere system and its implications for this region. The principal factor taken into account was the current state of the near normal sea surface temperatures (SSTs) over much of the tropical Indian and Atlantic Oceans. The near average SSTs are expected to remain largely normal during the next three months although the SSTs in the eastern tropical Pacific are likely to slide into warmer-than-normal conditions towards the end of the period. Coupled global ocean-atmosphere models, physically based statistical models and expert interpretation were used in the development of the outlook. The current status of seasonal forecasting methodologies allows prediction of spatial and temporal averages, and may not fully resolve all factors that influence regional, national and local climate variability.
The experts established probability distributions to indicate the likelihood of above-normal, normal or below-normal rainfall for each zone (see Map). Above-normal rainfall is defined as within the wettest 33.3% of recorded rainfall amounts in each zone; normal is defined as the middle 33.3% of the amounts while below-normal rainfall is the driest 33.3% of the recorded rainfall amounts.
January-March 2002 period:
Zone I: (Seychelles) Likelihood of normal rainfall
Zone II (Mauritius) Normal to above-normal rainfall
Zone III: (Northern sector of Tanzania) Above-normal to normal rainfall
Zone IV: (Northern half of DRC and extreme northwestern Angola) Normal to above –normal Rainfall
Zone V (Western and southern Tanzania, northern Mozambique, northern Zambia, northern half of Malawi, greater portion of southern DRC as well as central and eastern Angola) Likelihood of normal to above-normal rainfall.
Zone VI: (Southwestern Angola and northwestern Namibia) Rainfall is expected to be in the above-normal to normal range.
Zone VII: (Northern Botswana, eastern half of Swaziland, Zimbabwe, southeastern Angola, southern tip of the DRC, central and northeastern of Namibia, southern half of Malawi, central and southern Mozambique, extreme eastern South Africa and southern half of Zambia) Likelihood of normal.
Zone VIII: (Southern Namibia, southern half of Botswana, northernmost sections of South Africa) Likelihood of above normal to normal.
Zone IX: (Most of South Africa, Lesotho and western Swaziland) Normal to below normal.
Zone X: (Southwestern parts of South Africa) Normal to below normal.
These zones are shown on the attached Rainfall Outlook Map of JFM 2002.
The numbers for each zone indicate the probabilities of rainfall in each of the three categories: above-normal, normal and below-normal. The top number indicates the probability of rainfall occurring in the above-normal category, the middle number for the normal and the bottom for the below-normal. For example, Mauritius, (Zone II) there is a 35% probability for rainfall occurring in the above-normal category; a 40% probability for rainfall in the normal category and a 25% probability for a below-normal category. It is emphasized that boundaries between zones should be considered as transition zones.
CONTRIBUTORS
The Fifth Midseason Correction Forecast Meeting of the Southern Africa Climate Outlook Forum was convened in Harare, Zimbabwe 20 – 21 December 2001, by Drought Monitoring Centre-Harare (DMCH) in conjunction with Department of the Meteorological Services of Zimbabwe. Contributors to this consensus forecast included representatives of Meteorological Services from the following Southern African Development Community (SADC) countries: Botswana, Democratic Republic of Congo, Malawi, Mauritius, Mozambique, Namibia, Seychelles, South Africa, Swaziland, United Republic of Tanzania, Zambia and Zimbabwe. There were also climate scientists and other experts from SADC. Additional input was supplied by the International Research Institute (IRI), UK MET Office and European Centre for Medium Range Weather Forecasting (ECMWF). Users who participated in the deliberations of the forum contributed greatly in the final production of the statement.
Source:
Preliminary assessments from the Millennium Ecosystem Assessment, Southern African Millennium Ecosystem Assessment (SafMA, 2002), Nature serving the people: a pilot assessment of Southern African Ecosystems). Figures illustrate estimated cereal, water and biofuel availability and demand in the region (awaiting permission to use figures).
Figure 2 below: Cereal availability assessment (SafMA, 2002).
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