Climate data rescue 3: Bulletin Mensuel des Observations (BMO)

The collection recovered at Trappes comprises 119 issues (fascicles), each corresponding to one month: 1910: Jan, Feb, Mar (3 fascicles) 1925: Complete year (12 fascicles) 1926: Jan-Oct (10 fascicles) 1927: Complete year (12 fascicles) 1928: Complete year (12 fascicles) 1929: Complete year (12 fascicles) 1930: Complete year (12 fascicles) 1937: Complete year (12 fascicles) 1938: Complete year (12 fascicles) 1939: Jan-Jun (6 fascicles) 1940: Complete year (12 fascicles) 1941: Complete year (12 fascicles + 1 fascicle of supplement) 1942: Jul (1 fascicle) As can be seen, the number of lacks is very high.

There are particularly two big gaps: 15 years between 1910 and 1925 and 6 years between 1930 and 1937. In the current state of our research, it is still impossible to say whether these gaps are due to an incomplete collection of the Météo France in Trappes or to the fact that the BMO was not regularly published. The second hypothesis seems more likely, as the BMO collection held at the BNF has fewer issues than that of Météo France but has approximately the same gaps; and as the first page of the December 1930 issue bears the following information: "Publication of the BMO is suspended until further notice".