DOI: 10.23637/rmsmaairtemp1878-2024-01
title: Dataset: Monthly and Annual Air Temperature (Max, Mean, Min) at Rothamsted 1878-2024

description: The dataset provides the monthly and annual air temperature recorded at Rothamsted every year from 1878-2024.
The figure shows the maximum annual-maximums, the mean annual-means, and the minimum minimum annual temperatures, every year 1878-2024. It shows how all have risen, but in particular the minimum temperatures have risen most steeply over the 146 years of readings (minimum temperatures generally indicate night-time temperatures and hence it is these that have increased more). In addition, it can be seen that temperatures have in particular increased since the early 1980s.
description: Summary data used for this chart are derived from daily data measured at Rothamsted Meteorological Station. The average daily temperature is measured over a 24-hour period 0900 to 0900 GMT and calculated from the daily maximum (Tmax) and minimum temperatures (Tmin); the mean daily temperature = (Tmax = Tmin)/2. 

TMAX is recorded over the 24 hour period up to 0900GMT, for the previous day's maximum
TMIN is recorded over the 24 hour period up to 0900GMT, for the current day's minimum

Since 2004 recorded by thermistors (electronic temperature probes, Campbell Scientific, type 107). TMAX originally recorded using a mercury-in-glass sheathed column maximum thermometer and TMIN using a spirit-in-glass with indicator bar minimum thermometer, both housed in a naturally aspirating temperature screen.
description: An Excel file containing the following data for each year:-
Maximum maximum temperature; Mean maximum temperature; Minimum maximum temperature.
Maximum mean temperature; Mean mean temperature; Minimum mean temperature.
Maximum minimum temperature; Mean minimum temperature; Minimum minimum temperature.
Also, a chart of a subset of data (the extreme and mean annual temperatures). 

There are a few missing daily records and these are indicated in the data file by a highlight.
description: First recorded in 1878, Tmax was then measured using a mercury column thermometer and Tmin using a spirit-in-glass with indicator bar minimum thermometer. Data were collected daily manually until 2004 using a standard protocol. Since 2004 temperature has been recorded automatically by Automatic Weather Station thermistors (electronic temperature probes, Campbell Scientific, Type 107).

Location: Rothamsted Meteorological Station, Harpenden, Hertfordshire, England 51.82 N 0.37 W 128 m asl.
description: The monthly summary data contained in this spreadsheet are derived from daily data measured at Rothamsted Meteorological Station, Harpenden using MS Excel. Verification includes checks for instrument errors, for missing data and outliers. The original raw daily data is available, after registering, from the e-RA database. Please contact the e-RA Curators for an access password and further details. 

There are a few missing daily records and these are indicated in the data file by a highlight.

Sarah Perryman has curated this data together. Tony Scott is the current weather station manager who manages the recording equipment and data collection. We acknowledge the many people over the last 134 years who have taken these air temperature recordings starting with Thomas Wilson and Edwin Grey in the 19th Century (see Credits for information on more recent recorders and contributors).

For an history of the Rothamsted weather station recording see the 'Information' tab.