Reunion Island - Presentation
Guillaume JUMAUX Météo-France – Indian Ocean Climatology Division
SWIOCOF‐5, 19 to 23 September 2016 Seychelles Reunion island : Geographical situation
Somalie 700 km east to Kenya Madagascar
180 km west-south-west to Mauritius
Météo-France is the french national meteorological service. It is divided in 11 regions (7 in mainland France and 4 in overseas territories, including Reunion Island). Météo-France in Reunion Island is in charge of the data of Reunion Island, but also of Mayotte, and TAAF (scattered islands and austral and antarctic lands).
Page 2 Reunion island : Stations
Reunion island :
Reunion- 2500 km²: 2500 km² Mountainous- Mountainous island island (3070 (3070 m) m)
Trade- trade winds winds : contrast CyclonesEast/West world greatest rainfall (3930 mm, 3 days) - cyclones → world greatest rainfall amount in 3 days (3930 mm)
Stations Network :
- rainfall : ~ 90 stations 22 stations 1953-2015
- temperature : 47 stations 5 stations 1961-2015
Page 3 Mayotte : Stations
Mayotte : Reunion : 2500 km² - 376Mountainous km² island (3070 m)
- hillsTrade (660 winds m) Cyclones world greatest Stationsrainfall Network (3930 mm, : 3 days)
- rainfall : ~ 12 stations 4 stations 1961-2015
- temperature : 7 stations 1 station 1951-2015
Page 4 Precipitation : long term means
Annual rainfall amount :
500 mm to 10,000 mm in Reunion island 1,100 mm to 1,800 mm in Mayotte
Page 5 Monthly Precipitation
Heavy rainfalls, mainly during rainy season (Dec- Apr) :
Very little precipitation during dry season (May-Nov), except in southern and eastern regions → water resources issue need a regular hydrological monitoring
Page 6 Standard Precipitation Index (SPI)
Page 7 Drought Intensity in Reunion island (based on SPI)
No significant long-term trend - Too short sample (only 40 years) Page 8 - Strong variability with decennal cycles (90's, 10's are dry years) Rainy season 2015/2016 Dry season 2016
Page 9 Reunion Island : SPI in 2016
RAINY SEASON DRY SEASON SPI 4 months (Jan-Apr 2016) SPI 4 months (May-Aug 2016)
Page 10 Seasonal Outlook Forecast (based on SPI) : OND 2015
Oct-Dec 2015 Oct-Dec 2015 Downscaled Seasonal Forecast Observations Page 11 4 regions How to do seasonal forecast in Reunion Island (JAS 2016)
Page 12 An exemple : Downscaling model MSLP – Reunion
Page 13 An exemple : Downscaling model MSLP – Reunion
Page 14 An exemple : Downscaling model MSLP – Reunion ARPEGE FORECAST
Page 15 An exemple : Downscaling model MSLP – Reunion ARPEGE FORECAST ReunionStations (51 members)
Page 16 An exemple : Downscaling model MSLP – Reunion ARPEGE FORECAST ReunionStations (tercile prob.)
Page 17 An exemple : Downscaling model MSLP – Reunion ARPEGE FORECAST ReunionStations
Page 18 An exemple : Downscaling model CYCLONE ACTIVITY and track (exemple)
Page 19 An exemple : Downscaling model CYCLOGENESIS ZONE (exemple)
Page 20 THANK YOU
Page 21