Home: TRD: Resource utilisation: AGRI-OUTLOOK: NDVI FOR September 2008
Two approaches are used i.e. NDVI (plant activity) and PASG (accumulated seasonal greenness). It is expected that above normal rains of the current season should result in above normal conditions for plant activity. In general, all three images indicate at least similar to above normal plant activity or greenness, compared to last year and the long term. Interestingly, more plant activity was recorded in the east, which was ascribable to the nature of plants being more summer rainfall oriented. The western side of the province obviously had less plant activity or greenness due to the remarkably less acreage of actively growing or developing crops this time of the year. The green spots could probably be matched with eg. vineyards, orchards, potatoes (Sandveld), summer crops under irrigation, ect.
The current drought experienced in the mid Central Karoo is clearly pointed out in all three images. The fact remains that the drought is certainly abnormal, thus emphasising the appropriate aid to those producers in the affected area.
Other below normal situations (red) can also be seen, although being much smaller areas and isolated. These will be verified and if necessary carefully monitored and during the following months.
20 – 30 September 2009
NDVI values reflect the vegetation activity with higher values over the areas that experienced higher rainfall during the last few months.
21-30 September compared compared to 21-30 September 2008
NDVI values are lower than a year ago over most of the province but slightly higher over some areas in the southwest.
21 – 30 September 2008 compared with the long-term mean
Vegetation activity is somewhat higher than the long-term average the western and northwestern parts of the province, but lower than average over the southeastern parts of the province.
Percentage of Average Seasonal Greenness (PASG): April - September 2009 compared with the long-term mean
Percentage of Average Seasonal Greenness (PASG) for this period is above-normal over the northern parts of the province, but below-normal over the southeastern.
