Temperature time series recorded in Jena since 1821 based on daily observations

Observations 1820-2003 are from the Jena weather station ("Sternwarte"), 2004 to today from the MPI weather station, adjusted for the station location difference derived from an overlapping measurement period. A long-term trend curve superimposed by a seasonal cycle (4 harmonics, determined from the climatological period 1961-1990) has been fit to the daily observations.

Use the mouse to show popup-tooltips with the values at individual data points (takes a few seconds to load)

Figure 1. Annual mean temperatures since 1821. The early record until 1834 is suspicious because of station modifications (Orange points). The red line shows the long-term trend curve fitted to the annual mean temperatures. The vertical dashed line indicates the switch from the Jena weather station to the MPI weather station.

Figure 2. Daily mean temperatures of the last three years in the statistical context. The trend curve (thick blue line) reflects the long-term trend including the seasonal cycle as described above.  The statistics, ±σ and ±2σ sigma around the trend curve have been computed from the daily statistics of the climatological norm period 1961-1990. The grey lines labelled Min and Max show the all-time minimum, resp. maximum daily mean temperature ever observed at the Jena weather station (i.e. since 1820).

On the Min-and Max-curves, the popup-tooltips show the year and value of the observed temperature extremum.

Figure 3. Same as Figure 2 but for the last 12 months.

Figure 4. Same as Figure 2 but for the last month. The green curve shows for comparison the measurements taken by the DWD at the Jena weather station ("Sternwarte").

Trend of temperature extremes

Note that extrema after 2004 shown in the following graphs are estimated from the MPI weather station but adjusted to the Jena weather station ("Sternwarte") using statistics from an overlapping measurement period.

Figure 5. Graph of the days with a recorded temperature maximum larger than 33°C. The vertical dashed line indicates the switch from the Jena weather station to the MPI weather station.

Figure 6. Graph of the days with a recorded temperature minimum lower than -15°C. The vertical dashed line indicates the switch from the Jena weather station to the MPI weather station.

Graphs of the mean daily temperature for each year of observations are available in the subdirectory "Mean Daily Temperature Graphs" accessible through the link below:

Mean, minimum and maximum daily temperatures are available as a spreadsheet:

Last Update: Thu 7 Mar 2024 04:51:41

Links