Multiple Sites Monthly means from two or more measurement programs.

These problems account for the lower precision to which the early monthly means were quoted by Manley.

The daily variations during selected days of quiet geomagnetic activity are used to determine a monthly mean.

Upper panel: The mixing ratios from weekly flask pairs that started in 1977 are reported as monthly means for these major CFCs.

As a visual aid, the blue lines present monthly means of background data as they are presented under Recent Monthly CO2 at Mauna Loa.

The reanalysis data is packaged into monthly means from January 1958 to December 2008 (although five day means are also available) and stored in NetCDF format.

Measured monthly means from the different programs are statistically combined to create a long-term NOAA/ESRL GMD data set (black line).

But the monthly means from November to February show comparatively little variation and indicate an average winter population in the two Harbours of around 1,200 birds; at least some of the fluctuations in the winter counts must arise from the species' regular habit of feeding outside the Harbours in flooded fields, when these are available.

The high waters of the Winter/Spring period take the monthly mean to a level of between 9.2 and 12.6 m3/second, from January to May inclusive(with a maximum in March) and the low waters of late Summer/ early Autumn, August to October inclusive, with a minimum of 3.66 m3 in September.