Will GW increase NZ's sunshine hours?

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Manukau heads obs
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Will GW increase NZ's sunshine hours?

Unread post by Manukau heads obs »

I put it out there that Global warming is going to increase sun shine hours here :)
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Brian Hamilton, weather enthusiast. My weather dataEmail: [email protected]
melja
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Re: General November Weather

Unread post by melja »

Thought warmer sea made more clouds :-k
Manukau heads obs
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Re: General November Weather

Unread post by Manukau heads obs »

alot of the time, warm air masses pick alot of moisture/cloud over cooler water temperatures...as they warm (the sea surface) up...there will be less of that happening (and a warmer air mass can hold more moisture...so actually everything being equal, will mean less clouds...but given the triggers has more rain potential
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Brian Hamilton, weather enthusiast. My weather dataEmail: [email protected]
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NZstorm
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Re: General November Weather

Unread post by NZstorm »

Manukau heads obs wrote:I put it out there that Global warming is going to increase sun shine hours here :)
Under the climate change scenario the subtropical subsidence ridge will strengthen over the north of the country during the summer months leading to less rainfall and higher sunshine hours. So the Bay of Plenty arguably could become the sunniest part of NZ. And Auckland becomes sunnier as well.
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Nev
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Re: Will GW increase NZ's sunshine hours?

Unread post by Nev »

Interesting discussion. 8) Thought it might warrant a thread... :-)
RWood
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Re: Will GW increase NZ's sunshine hours?

Unread post by RWood »

First we'll have to finish migrating to a consistent measuring method - at present the data is "all over the place".

As a point which might be vaguely related to the subject - poleward migration of the southern ocean jetstream - which may or may not be an artefact of warming - has already had a noteworthy effect on Perth and the SW corner of WA generally - rainfall has decreased and sunshine increased.
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tgsnoopy
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Re: General November Weather

Unread post by tgsnoopy »

NZstorm wrote:So the Bay of Plenty arguably could become the sunniest part of NZ. And Auckland becomes sunnier as well.
Umm, isn't Whakatane claiming the title these days (or trying to), so one might argue it's already happening? :P
NZ Thunderstorm Soc
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Re: Will GW increase NZ's sunshine hours?

Unread post by NZ Thunderstorm Soc »

dunno?
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RWood
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Re: General November Weather

Unread post by RWood »

tgsnoopy wrote:
NZstorm wrote:So the Bay of Plenty arguably could become the sunniest part of NZ. And Auckland becomes sunnier as well.
Umm, isn't Whakatane claiming the title these days (or trying to), so one might argue it's already happening? :P
Whakatane is merely one of many cases where the electronic readings are giving much higher values - by 150 to 400 hrs per annum - than manual equipment in the same locations did. When apples were compared with apples (manual era) Whakatane was clearly lower than Nelson and Blenheim - in 45 years or so of records it won just twice, with Blenheim, Nelson or Motueka taking the rest - apart from a single year for Mt John.

Much lower on the scale, a Balclutha site is topping an older manual one in that region by over 400 hours/year
I could go on ... while exposures in some cases have been improved, there are far too many anomalies to be explained away.
jamie
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Will GW increase NZ's sunshine hours?

Unread post by jamie »

But are the automatic ones consistent between them? If yes then once we have auto across all key sites it shouldn't matter about old method results.
spwill
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Re: Will GW increase NZ's sunshine hours?

Unread post by spwill »

From Niwa website regarding Whakatane sunshine hrs,
https://www.niwa.co.nz/news/whakatane-s ... s-released
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NZstorm
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Re: Will GW increase NZ's sunshine hours?

Unread post by NZstorm »

I suspect annual sunshine could drop a little over the South Island due to more upper level cloudiness.
RWood
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Re: Will GW increase NZ's sunshine hours?

Unread post by RWood »

jamie wrote:But are the automatic ones consistent between them? If yes then once we have auto across all key sites it shouldn't matter about old method results.
That's a good question. There have been plenty of issues. I pointed out to Niwa when Queenstown Aero values suddenly dropped dramatically - the instrument had to be replaced. Franz Josef (not renowned for sunshine) has had more than one run of absurdly high values, and currently this has been happening for over a year. A comment from the UK from someone comparing equipment types was that the type used here (Kipp-Zonen is the name I think) could "drift in calibration" readily. Re Whakatane, see my other post.
RWood
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Re: Will GW increase NZ's sunshine hours?

Unread post by RWood »

spwill wrote:From Niwa website regarding Whakatane sunshine hrs,
https://www.niwa.co.nz/news/whakatane-s ... s-released
That was over 5 years ago, and Whakatane "anomalies" have increased since. Last year's tally of more than 300 hours ahead of Nelson and Blenheim is just plain ridiculous. Note also the caveat at the end of NIWA's 2009 report.
And now one has New Plymouth with similar anomalies - both centres' annual totals were over 400 hours more than their old manual averages. Stations further "down the list" (like Franz Josef) don't get noticed because even their inflated values will never "compete".