Dredd Blog: "Last" Doesn't Always Mean "Previous"

Wednesday, January 21, 2026

"Last" Doesn't Always Mean "Previous" - 5

In the previous post I mentioned a source of information associated with a paper in a scientific journal (Lundstad, Elin; Brugnara, Yuri; Brönnimann, Stefan (2022): Early instrumental time series of global measurements of monthly precipitation between 1677-2021, part 1 [dataset]. PANGAEA, https://doi.org/10.1594/PANGAEA.941263; In: Lundstad, E et al. (2022): Global Early Instrumental Monthly Meteorological Multivariable Database (HCLIM) [dataset bundled publication]. PANGAEA, https://doi.org/10.1594/PANGAEA.940724).

I have graphed the "pressure" data (called "d_si" in the previous post's graphs.

The difference in "d_si" in the previous graphs and in today's graphs is simply that the previous graphs used data generated by values calculated using anomaly values (anomalies are values that vary from values within a specified span of time).

The graphs today are generated using the values in the aforesaid Lundstad et al. dataset.

I used only values from 1850 on so as to make it easier to compare with the previous post's graphs which began in 1850.

Today's Lundstad graphs use "Layer" and "Zone" terms to describe the locations from which the d_si (pressure) values originated.

A "Layer" in this context is a Latitude band as shown in the graphic at the top of the page, and a zone is a rectangular area bounded by longitude lines.

One thing which I noticed that seems to validate some of the Lundstad data ("Climate change caused by human activities is influencing atmospheric pressure, according to a new study. The research, published in this week’s Nature, is the first report of a human-induced effect on global climate that does not rely on measurements of temperature." - see previous post in this series) is that pressure does vary for various reasons.

Anyway, more to come after I process the Lundstad temperature data.

The previous post in this series is here.