0000000001148722
AUTHOR
Marie-jeanne Sambou
Heat wave occurrences over Senegal during spring: regionalization and synoptic patterns.
18 pages; International audience; Based on 12 Senegalese stations of the Global Summary of the Day (GSOD) database (1979–2014), heat waves (HW) are defined for each station in spring (March–April–May, the hottest season in Senegal) as the daily maximum temperature (Tx), minimum temperature (Tn), or average apparent temperature of the day (AT), exceeding the corresponding 95% mobile percentile for at least three consecutive days. A hierarchical cluster analysis used to regionalize HW in these 12 stations is applied to simultaneous occurrences of daily temperature peaks over their 95% mobile percentiles. Three homogeneous zones of four stations each are identified (Zone 1, Zone 2 and Zone 3),…
Les vagues de chaleur au Sahel : caractérisation, mécanismes, prévisibilité.
The mechanisms controlling Sahelian heat wave (HW) variability are examined on the period 1979-2014 using the GSOD observational database and ERA-Interim reanalyses. HW events are analyzed through all terms of the atmospheric energy balance, showing a predominant role of incoming shortwave radiation on daily maximum temperature (Tx) and atmospheric water vapor on minimum temperature (Tn). The low-frequency warming trend, not explained by the previous terms, is thought to relate to the increase of greenhouse gases concentrations, due to anthropogenic emissions. The predictability of Sahelian HW events is assessed for lead times reaching up to 15 days. The model's skill, biases and uncertaint…