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In Bietigheim-Bissingen the temperatures rise to 21.8 degrees. Is this normal for this time of year or is it already climate change? Here we compare the current weather in Bietigheim-Bissingen with the long-term trend.
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Is the weather normal in Bietigheim-Bissingen (postal code 74321) today? Is it too hot or too cold, too dry or too humid for the time of year? The answer comes from data from the weather station in Stuttgart (Schnarrenberg).
Temperature today: up to 21.8 °C. That’s unusually warm.
What is considered “normal” is the long-term mean measured at this station. “Unusual” are values that clearly deviate from this. We compare the current weather data in Stuttgart (Schnarrenberg) with the periods 1961 to 1990 and 1991 to 2020. The comparison with 1961 to 1990 shows long-term changes in the climate – among other things as a result of man-made climate change. In many places, climate change has accelerated in recent years. This is shown by a comparison with the period 1991-2020.
The colored line shows the daily maximum temperatures for the past few weeks to date (highlighted as a circle). If the line is above or below the normal gray area, it is unusually warm or cold. We show the normal range because it is more robust to random fluctuations in the weather than the pure mean (dashed line) comparison. The same comparison can also be made for the lowest temperature measured on a day:
Unusually warm and cold temperatures are outside the normal gray area in our model. The following table shows how large the fluctuation can be on one day over the decades:
How much it is currently raining – and what would be normal
Rain in the last 30 days: 44.3 mm. That’s normal a lot.
Precipitation can also be compared with long-term measurements. However, the amount of rain on a single day varies much more than the temperature. Therefore, this diagram not only shows the rain on one day, but each point represents the sum of the last 30 days. The same applies here: If a point is outside the gray normal area, it was unusually wet or dry in a long-term comparison.
What climate change has to do with it
There can be outliers even without climate change. The fact that the climate is changing only becomes apparent in long-term trends. We can not only calculate whether it is getting warmer overall, but also whether it is getting hotter more often in summer or colder and colder less often in winter. Such a tendency is manifested on so-called hot days, summer days and frosty days. On hot days, 30 degrees or more are measured, on a summer day 25 degrees or more, on a frosty day the temperature falls below freezing.
Summer days from 25 °C: 0 since March. The month in which these days occur varies from year to year, but since 1961 the number has increased.
How many days like this have happened since March? How many were there in total in the past summer months?
The trend line shows the development since 1961. If, for example, the number of hot days has increased over the decades, this indicates increasingly frequent and longer heat waves. On the other hand, if the number of frosty days falls, the weather tends to be milder in the colder months.
The “climate strips” diagram shows that due to climate change, Bietigheim-Bissingen is also getting warmer overall.
Each climate strip represents a year. Blue means the average temperature that year was below the long-term mean from 1961 to 1990. Red means that the year was warmer. The stronger the red, the warmer the year was in comparison. These increasingly hotter and hotter years are becoming more frequent in recent years.
So far, climate change has had less of a clear impact on precipitation. In Baden-Württemberg it rains a little less overall in summer, although drought and heavy rain increasingly alternate. Winters tend to be wetter.
sunshine hours
The number of hours of sunshine is important for the well-being of many people. This is how often the sun recently came out in Bietigheim-Bissingen:
How much and how long the sun shines also varies depending on weather developments, but according to the current state of research has little to do with climate change. In the past, long-term changes were mainly caused by cleaner air.
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