Global cloudening? - Forums

This question has popped up a few times and personally i feel like there are >100% cloudy nights these days so I wrote a python script that goes throug all my raw files and creates some statistics for total exposure times over the years.
I started using Nina in 2020 and using my rig over night, greatly increasing my integrated exposure time.

Total integrated exposure per year for January (and total):
2018: 0.0h ( 9.7h)
2019: 6.3h ( 48.3h)
2020: 12.6h ( 130.5h)
2021: 9.0h ( 161.9h)
2022: 40.8h ( 325.9h)
2023: 20.8h ( 215.9h)
2024: 33.5h ( 33.5h)

Turns out my "feeling" was wrong. Within expected variations, the amount of availavble clear nights has not decreased over the years if we assume that 2022 was an outlier.

I can say for sure that in my area of Sydney Australia the cloud from Dec to Feb has increased dramatically since 2022. All sorts of strange cloud. Usually a cloud blanket of fine cloud covering every inch of the sky for weeks on end. I have been imaging from year 2005 and I don't recall this type of cloud at the end of the year.

There might be undulations in the cloudiness ratios due to climate phenomena like El Nino/Southern Oscillation (ENSO), the North Atlantic Oscillation (NAO), and other similar ones e.g. in the Indik. ENSO happens every several years. To overcome those, you have to capture more data, say 25 years ;)

In the past, ENSO has been understood as a more or less local phenomenon, today we know it has global consequences and can sometimes amplify its pendants.

There are so many short term factors. El nino, vulcanism, solar max, “climate modification” by all the major players, global “supply chain”, increased air traffic…

Believe it or not, wind farms are a contributing factor as well and actually CONTRIBUTE to “global warming” and more violent weather.

Sean Mc:
solar max,

Solar max has a large influence on the upper atmosphere, but there is no obvious correlation to cloud cover, that would show up in local weather. At least not that i knew of.

Coolhandjo:
I can say for sure that in my area of Sydney Australia the cloud from Dec to Feb has increased dramatically since 2022. All sorts of strange cloud. Usually a cloud blanket of fine cloud covering every inch of the sky for weeks on end. I have been imaging from year 2005 and I don't recall this type of cloud at the end of the year.

As a fellow resident of Sydney I certainly agree. Even though I've been doing astrophotography only for a couple of years, the last few months have been particularly bad for clouds. What's really annoying is go to bed under a cloud cover and wake up to crystal clear skies, like today 😡

Frank Alvaro:
Coolhandjo:
I can say for sure that in my area of Sydney Australia the cloud from Dec to Feb has increased dramatically since 2022. All sorts of strange cloud. Usually a cloud blanket of fine cloud covering every inch of the sky for weeks on end. I have been imaging from year 2005 and I don't recall this type of cloud at the end of the year.

As a fellow resident of Sydney I certainly agree. Even though I've been doing astrophotography only for a couple of years, the last few months have been particularly bad for clouds. What's really annoying is go to bed under a cloud cover and wake up to crystal clear skies, like today 😡

*** yes. And also forecast says clear. And at sunset crystal clear skies. Recheck forecast all clear for rest of night. Set up and then like clockwork as soon as Sun sets a thin blanket of cloud covers the entire sky all night until dawn. It's very very strange and happens a lot lately ***

Coolhandjo:
I can say for sure that in my area of Sydney Australia the cloud from Dec to Feb has increased dramatically since 2022. All sorts of strange cloud. Usually a cloud blanket of fine cloud covering every inch of the sky for weeks on end. I have been imaging from year 2005 and I don't recall this type of cloud at the end of the year.

Same in Brisbane.... I was into imaging from 2008 - 2013 and just came back into the hobby in November 2023. I think I've had 6 REALLY clear nights nice November 2023, with a few 'OK' nights... I was CERTAIN that it was never this bad back in the late 2000's / early 2010's

Probably, we would all need to fly to the I.S.S. to make astrophotos…. This December-February in Canada are so cloudy, barely few nights clear…

This is a very interesting work. Glad you did it. Comparing the data of 7 years is a good starting point. But I think it's not enough for finding trends in the weather data, because I think it's a process that changes very slowly. But I guess that's all you have. So I'm not judging your work.

When I think of some of the things that happened during the last years, I remember a summer of many clear nights without a drop of rain at all for months. On the other hand, last year I wasn't able to record some single image from december to early march, because there was no clear night at all. This shows, how far apart the conditions are, which makes it even harder to find serious trends in your data.

But I would like to hear whats going on after the next coming years. So please keep the script and share some more information later.

CS

Christian

I mainly did this little project to test the capabilities of Googles Gemini (formerly Bard), to see if it could generate this python script for me. It failed catastrophically and I had to write most of it myself. I can share the script later if anyone wants to run it on their own data, it's fully automated and accepts all relevant parameters as command line input.

D. Jung:
test the capabilities of Googles Gemini (formerly Bard), to see if it could generate this python script for me

As a software engineer who does use AI assistance, I can tell you it can be fantastic for optimisation of code, but rarely does a reasonable job of creating something from scratch, even when you define the parameters, and required result exceptionally well.

I've had it cut execution time of a particular method down by nearly 20% in the past, and plenty of times where there is no immediate performance benefit, but the memory usage is reduced dramatically. I've not once had a situation where an even remotely acceptable method written for me entirely for a moderately complex task...

Florida is the Sunshine State for a reason, but this winter has been anything but sunny. And the cloudy and stormy trend looks to continue for the rest of winter and into spring.

Maps created by climatologist Brian Brettschneidershow that Florida is in the midst of its cloudiest winter on record. Records go back 84 years.

And if you’re wondering why, all of this is thanks to a very active subtropical jet stream induced by El Nino.

During a strong El Nino, which the winter of 2023-24 is currently in, the jet stream blasting from the Pacific Ocean and over the Gulf of Mexico keeps the conveyer belt of moisture and disturbances flowing through Florida.

Lived here for 22 years with clear dry skies from November to May. This year, totally different.

Mike H - Sky View Observatory:
Florida is the Sunshine State for a reason, but this winter has been anything but sunny. And the cloudy and stormy trend looks to continue for the rest of winter and into spring.

Maps created by climatologist Brian Brettschneidershow that Florida is in the midst of its cloudiest winter on record. Records go back 84 years.

And if you’re wondering why, all of this is thanks to a very active subtropical jet stream induced by El Nino.

During a strong El Nino, which the winter of 2023-24 is currently in, the jet stream blasting from the Pacific Ocean and over the Gulf of Mexico keeps the conveyer belt of moisture and disturbances flowing through Florida.

Lived here for 22 years with clear dry skies from November to May. This year, totally different.

*** yes and it all ends up in Australia! ***