John Dee's Climate Normal

John Dee's Climate Normal

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John Dee's Climate Normal
John Dee's Climate Normal
Antarctic Land Surface Temperature (part 4)

Antarctic Land Surface Temperature (part 4)

In this episode I take a closer look at the land surface temperature record of Orcadas base for the period 1903 – 2023 and reveal some hidden secrets

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John Dee
Jun 09, 2023
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John Dee's Climate Normal
John Dee's Climate Normal
Antarctic Land Surface Temperature (part 4)
22
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Right at the very end of part 3 of this series I produced the following screenshot of the annual mean temperature for Orcadas for 1903 – 2006:

If we grab a coffee we may pause for elevenses to ponder on the following questions:

  1. How come this series goes back to 1903 when I previously showed data for Orcadas starting in 1957?

  2. How come this series stops in December 2006?

  3. How come an x-axis running from 1870 to 2020 is used to show data from 1903 to 2006?

  4. How reliable are these annual means?

Now grab a slice of cake and consider these answers:

1. Because the GHCN-D daily dataset starts in 1957 but the GHCN-M monthly dataset for Orcadas starts in 1903. I had assumed that the two databases would yield equivalent data spans but this (mysteriously) is not the case and so I shall be digging out the monthly series for all stations for comparison. The problem with the monthly series is that we don’t know if a datum is just one measurement made on one day or an average derived from multiple measurement…

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