User talk:Uness232/Archives/2022/September

Request
Hello.

Can you find up-to-date and importantly reliable data about Istanbul's climate? The Turkish Meteorological Service rarely publishes up-to-date and detailed data (about individual cities, let alone districts, hardly at all). And if they do, it is usually general national and regional data. And after a while, they disappear too from its website. Furthermore the data seem to be old and unreliable (just like the institution itself and like all Turkish state institutions in general). Even the actual climate types of Turkish cities are not stated. For instance, due to an increase of average temperatures, the climate of almost the entire Black Sea coast has undergone a change from a temperate oceanic or temperate oceanic/humid subtropical borderline case to a fully humid subtropical climate. Likewise Istanbul, which used to have a much lower annual precipitation of 500-580 mm and a full mediterranean climate five decades ago, and which has become wetter over the past four decades, is still depicted as having a borderline oceanic/humid subtropical/mediterranean climate. Because of consistently much higher precipitation levels in each summer month since the 2000s, and especially since the 2010s, the climate of the entire city has evolved into a humid subtropical climate (as well as many other areas in the Marmara region). Yet the Turkish Meteorological Service do not have up-to-date data about these changes. Can you find any up-to-date and reliable data?

Yours sincerely, Multituberculata (talk) 09:21, 31 August 2022 (UTC)


 * Hi,
 * I have worked on increasing thew reliability and coverage of Istanbul's climate data, however: some of the claims you present are not wholly accurate. The TSMS isn't wholly reliable but usually quite up-to-date.
 * On your claims:
 * For instance, due to an increase of average temperatures, the climate of almost the entire Black Sea coast has undergone a change from a temperate oceanic or temperate oceanic/humid subtropical borderline case to a fully humid subtropical climate.
 * This is somewhat true but is not because of global climate change: most of this is rather because of the urban heat island, and therefore, rural areas still do have oceanic climates. Unfortunately, we don't have rural coverage of the Black Sea coast, but this is obvious when looking at places like Cengiz Topel NAS.
 * Likewise Istanbul, which used to have a much lower annual precipitation of 500-580 mm and a full mediterranean climate five decades ago, and which has become wetter over the past four decades, is still depicted as having a borderline oceanic/humid subtropical/mediterranean climate. Because of consistently much higher precipitation levels in each summer month since the 2000s, and especially since the 2010s, the climate of the entire city has evolved into a humid subtropical climate (as well as many other areas in the Marmara region).
 * There is no data that indicates that Istanbul's rainfall is increasing at such a rapid rate. Both station data and model data support either a very modest fall, or a very modest rise. In fact, the differences in maps are not about older and newer data, but about different thresholds for the Mediterranean climate (30mm would make most of the city humid subtropical, 40 would make most of it Mediterranean) So, the only change that you would expect Istanbul to undergo is the erosion of its Oceanic climate: which I'm yet to find the data to support. Uness232 (talk) 12:26, 31 August 2022 (UTC)


 * Thank you for all the data. There is also a degradation of the mediterranean climate. Even the driest southern parts of Istanbul receive rainfall each summer month which exceed not only the minimum threshold of 30 mm, but also the maximum threshold of 40 mm. While there is no particular increase in the number of days with rain each summer month, the rainfall amount has noticeably increased and the downpours have become heavier, and is sometimes double, triple or four times the monthly average. This is happening practically every summer, and most summer rains are causing some flooding. Apart from the urban heat island phenomenon of Istanbul, surely climate change is a factor as well. Multituberculata (talk) 13:58, 31 August 2022 (UTC)
 * This would have come with a noticeable annual precipitation increase, which hasn't happened. If you have data (even for one year) that shows anomalous numbers, please do show me. Of course climate change is a factor, but in city center temperatures, urban heat island is often a bigger one. Uness232 (talk) 17:25, 31 August 2022 (UTC)


 * Unforuntately I have not found any up-to-date and very comprehensive data about historical monthly precipitation amounts. For instance precipitation amounts are sometimes mentioned in news articles, but academic and especially official data about these are extremely hard to find. These are a few examples (unfortunately only) from the media from the past three months:


 * https://www.sozcu.com.tr/2022/gundem/istanbulda-en-fazla-yagis-sariyere-dustu-dakikada-65-simsek-cakti-7242074/ 10.7.2022


 * https://www.haberturk.com/istanbul-da-yagmur-imamoglu-ndan-son-dakika-aciklama-metrekareye-50-100-kg-yagis-dustu-yagis-1500-te-3511263 15.08.2022


 * https://www.sozcu.com.tr/2022/gundem/istanbulda-metrekareye-69-kg-yagis-dustu-7328842/amp/ 25.08.2022


 * So I don't hold my breath (about finding such data), or maybe I should. Multituberculata (talk) 11:49, 3 September 2022 (UTC)

These are mostly normal, though. For a city that gets a measly 4 days of rain a month and 30-40mm of rain a month in summer; what is likely to happen is a series of months with litte precipitation (between 0-10mm) and others with 50-100 mm. Climate change has likely pushed this dynamic even further, but more rain in general is not something that we can presume from this. Uness232 (talk) 22:18, 3 September 2022 (UTC)