From Berlin to Brooklyn: Chasing the Sun
What two cities — and a lot of rain — taught me about weather, comfort, and climate change.
When I moved from Berlin to Brooklyn, my friends told me to look forward to the beautiful weather here. Berlin is rarely sunny, they said. You will love it there. So far, I’m not convinced. I mean ...
There was a lot of rain in Brooklyn this year. Berlin, on the other hand, looked sunny and nice. Is Berlin’s weather really not as bad as its reputation?
To really settle this, we need to look deeper. Let’s start with sunshine hours from the past year.
To define a sunny day, I followed the definition used by the German Weather Service (DWD): a sunny day is a day with at least 80 percent sunshine.
So, yes — Brooklyn definitely got more sunny days over the last year. Especially the winter months in Berlin were exceptionally sunless. Overall, Brooklyn had 78 more sunny days than Berlin.
How bad was spring in Brooklyn?
But if we look at just the past three months, it’s hard to say if Brooklyn’s weather was really that bad — or if Berlin’s was just unusually good. A ten-year comparison makes things a bit clearer.
The sun ratio - the duration of sunshine per day divided by the possible hours of daylight could be an indicator for this. This also factors in, that Berlin has longer days in summer and much shorter days in winter.
In fact, Berlin in winter feels like there is no sun at all, while Brooklyn winters seemed sunnier. Is this true? Let's take a look at average sun ratio per month.
Berlin winters felt like the darkest times — and this chart proves it: in December, there is sometimes not more than 20 percent sunshine per day on average.
On the same hand, this spring, Brooklyn's sun ratio was down compared to the previous years. Thus, the impression of rainy weekend's was not so off after all.
But what about the humidity?
A hot summer day in Brooklyn feels so much hotter than in Berlin. The only explanation: humidity. High humidity prevents sweat from evaporating, making it feel hotter than it is.
If we look at humidity in relation to the “feels like” temperature, it shows just how humid Brooklyn is year-round — and how that makes summer especially uncomfortable. In Berlin, summers have more of a dry heat and therefore, feel more pleasant.
The humidity makes Brooklyn’s climate feel more extreme. And with climate change, it’s only going to get worse — in both cities.
Just weather or already climate change?
The Earth has warmed by one degree, according to NASA calculations. But when is weather still normal — and when is it already climate change? A long-term comparison reveals a clear trend.
That trend shows: both cities are getting warmer — Berlin especially.
If a year was warmer than the climate reference period from 1961 to 1990, the bars are red. If the month was colder, it’s blue. The longer the bar, the higher the deviation.
Over time, the red years pile up. The deviations get stronger. It’s getting hotter — more often — in both Berlin and Brooklyn.
Weather data comes from the Open-Meteo API, which provides historical hourly weather records. I downloaded historical data for both Berlin and Brooklyn from 1940 to 2025 and used the API for current weather updates.
To define sunny days, I calculated monthly sun ratios by dividing sunshine hours by total daylight hours. Following the definition from the German Weather Service (DWD), I flagged days as "sunny" if they reached at least 80% of possible sunshine.
To explore the effects of climate change, I calculated average yearly temperatures based on daily mean values. The temperature chart is color-coded using the Datawrapper API.
All analysis was done in Python using Pandas and Matplotlib. You can view the full code and data in the GitHub repository.