National Climate Database open for free access! :)

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Andy
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Re: National Climate Database open for free access! :)

Unread post by Andy »

RWood wrote:OK, here's the first step. Get registered. Remember, now it's all free for standard data access (if you want to do some calculation that's not already stored they will make a small charge to do it for you).

http://cliflo.niwa.co.nz/pls/niwp/wsubform.intro" target="_blank" target="_blank

Next is login, but let's take it one step at a time.
Ok done
RWood
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Re: National Climate Database open for free access! :)

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From here or similar, select Login and use the userid and set your password (if that hasn't already been chosen during registration) to complete the login.

http://cliflo.niwa.co.nz/" target="_blank
RWood
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Re: National Climate Database open for free access! :)

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To make things easier, if you tell me just what kinds of info. you want for Alexandra, I can guide you through the rest of the process more easily by doing a mock request (preview) myself and describing what I did.
Andy
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Re: National Climate Database open for free access! :)

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RWood wrote:To make things easier, if you tell me just what kinds of info. you want for Alexandra, I can guide you through the rest of the process more easily by doing a mock request (preview) myself and describing what I did.
Ok can we start with rainfall. Yearly totals;

Ta :D
Gary Roberts
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Re: National Climate Database open for free access! :)

Unread post by Gary Roberts »

Andy wrote:Ok can we start with rainfall... :D
Omarama: 142 mm of rain since 09:00, 01/01/07.

:P :P :P :P
Andy
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Re: National Climate Database open for free access! :)

Unread post by Andy »

Omarama: 142 mm of rain since 09:00, 01/01/07.
Is that all Alexandra 181mm since 01/01/07 =D>
Gary Roberts
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Re: National Climate Database open for free access! :)

Unread post by Gary Roberts »

Andy wrote:Is that all Alexandra 181mm since 01/01/07 =D>
See? Not only am I much better than you but my town is much better than your town!

:twisted: :P :lol:
RWood
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Re: National Climate Database open for free access! :)

Unread post by RWood »

Andy wrote: To make things easier, if you tell me just what kinds of info. you want for Alexandra, I can guide you through the rest of the process more easily by doing a mock request (preview) myself and describing what I did.
Ok can we start with rainfall. Yearly totals;

Ta :D
OK: (you can get more than one data type at a time, but one is enough for learning the method!)

1. Login as described, takes you the Database Query page.
2. Click on "select datatypes" button found under "1.Datatype"
3. Click on "Combined Statistics Calculated from Obervations" (monthly & annual in tabular format)
4. You want actual observations, not averages, so click on "Monthly and Annual Statistics". I don't think you can get annual without monthly, but you're not paying, so what the hell!
5. Select "Rain", then check box "total rainfall", click "Add". You should see a "00" appear on the query form (just under the words "select options").
6. You want to select the various sites Alexandra has used (will generate a table for each). Click on "Choose Station(s)" under "2.Location".
7. Under the radio button "station Name", type Alexandra in the box. Click the "Get Station(s)" button at the bottom of that form.
8. The resulting listing "Station List" will show you 4 stations with some overlap in the later years, both the last 2 have incomplete records (90% and 50%). You probably want to select all of them in the 4 check boxes.
9. Click "Add Station(s) button" below the list.
10. Back on the Query form, you'll see 4 "station agent numbers" have appeared on the query form under "2.Location".
11. Under "3.Date/Time", enter 1922 and 2007 for start and end, to cover all the years for all 4 stations.
12. Under "4.Format", choose your file download option.
13. You can now test your query by clicking "preview" near the bottom of the form. Looks good when I tried it.

Try this for real by now clicking "Send Query" - your file should be downloaded (4 tables of monthly and annual totals).
I won't do it yet, as it'll reduce my budget left unnecessarily (though its' free so not really important).

Good luck!
RWood
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Re: National Climate Database open for free access! :)

Unread post by RWood »

Andy wrote:Omarama: 142 mm of rain since 09:00, 01/01/07.


Is that all Alexandra 181mm since 01/01/07 =D>
Tara Hills AWS has 184mm for 01/01/07-30/06/07. A different site I presume?
Gary Roberts
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Re: National Climate Database open for free access! :)

Unread post by Gary Roberts »

Tara Hills AWS has 184mm for 01/01/07-30/06/07. A different site I presume?
Their station is 8.5km SW of mine, down Broken Hut road and routinely cops a little extra rain and lower temperatures..
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Re: National Climate Database open for free access! :)

Unread post by janewaystv »

Great to read the posts on this thread :D .

I have some questions - I have been looking for sunshine data under the name of Hamilton to no avail, Im wondering if it is known as another name, if so, please put down for me.

Oamaru has sunshine records from 1961 to 1985 at Oamaru Airport (5141) & Iona Hospital (5407) - can't find any more from 1986 onwards - do they still record sunshine for Oamaru or not?

Whangarei only recorded sunshine from 1954 to 1993, do they nowadays record under a different name or not? As I only have Whangarei Hospital (1284) and Whau Valley (1285).

Nelson's sunshine hours are very similiar to Sydney's as well as Blenheim, Napier and Tauranga as well. Certainly surprised after reading sunshine totals for New Plymouth - quite a sunny place in spite of the high rainfall, same for Westland but to a lesser extent.

Great reading Milford Sound & Stewart Island rain data. Interesting to note that Bluff & Tiwai Point (Southland) records less rain than Invercargill, Tiwai Point is just opposite Bluff although separated by a narrow channel of the sea.
jrj
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Re: National Climate Database open for free access! :)

Unread post by jrj »

Question: where do I find the station numbers/names? Specifically Napier and Hastings?
RWood
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Re: National Climate Database open for free access! :)

Unread post by RWood »

James wrote:Question: where do I find the station numbers/names? Specifically Napier and Hastings?
You can do as under point 7 on my list - or choose the "regional" option which will give a pile of stations. The surefire method is to click a region and select the stations you want from the generated list.
Last edited by RWood on Wed 01/08/2007 11:11, edited 1 time in total.
RWood
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Re: National Climate Database open for free access! :)

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janewaystv wrote:Great to read the posts on this thread :D .

I have some questions - I have been looking for sunshine data under the name of Hamilton to no avail, Im wondering if it is known as another name, if so, please put down for me.

Oamaru has sunshine records from 1961 to 1985 at Oamaru Airport (5141) & Iona Hospital (5407) - can't find any more from 1986 onwards - do they still record sunshine for Oamaru or not?

Whangarei only recorded sunshine from 1954 to 1993, do they nowadays record under a different name or not? As I only have Whangarei Hospital (1284) and Whau Valley (1285).

Nelson's sunshine hours are very similiar to Sydney's as well as Blenheim, Napier and Tauranga as well. Certainly surprised after reading sunshine totals for New Plymouth - quite a sunny place in spite of the high rainfall, same for Westland but to a lesser extent.

Great reading Milford Sound & Stewart Island rain data. Interesting to note that Bluff & Tiwai Point (Southland) records less rain than Invercargill, Tiwai Point is just opposite Bluff although separated by a narrow channel of the sea.


Hamilton is known as Ruakura (it is or was an Ag. Research place). If you're unsure of a name, pick a regional list to get a heap of stations.

Oamaru has no data since 1985. It will be one of many added later as an EWS in due course, I'm sure. (Note: its old 1929-1953 town records have been dropped - I'm not surprised, as they were a bit dodgy. Either that or they've never entered them into the new databases. (See also my comment on old In'gill sun records on Weatherzone!)

Whangarei - probabaly another on the EWS queue. No data since 1993 (note - the values there post-1987 are decidedly fishy).

A new station at Whakatane opened this year to resume sun data - probably electronic I think.

A lot of people are unaware of the N Plym. values. It has topped the country on a number of occasions. High recent values include 229 in 8/2006, 269 in 2/2007. Remember my "looking back" for July 1973?

Nelson and Blenheim will never really match Sydney - will always be 150-200 hrs short. Not bad for temperate maritime though!

Are your Bluff, TP and In'gill averages over the same periods?
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Re: National Climate Database open for free access! :)

Unread post by jrj »

Success, thanks :D
Andy
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Re: National Climate Database open for free access! :)

Unread post by Andy »

Thanks =D>
RWood
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Re: National Climate Database open for free access! :)

Unread post by RWood »

Andy wrote:Thanks =D>
NP... :) If you want to get annual totals/means for other variables for Alex. sites (temp, sunshine, wind, pressure etc.) (and remove ones you've already got the data for) you just go into the Dataype selection button - quite easy.

If you want 30-year monthly/annual normals, the dates are interpreted differently (see the help).
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Re: National Climate Database open for free access! :)

Unread post by janewaystv »

RWood wrote:
Hamilton is known as Ruakura (it is or was an Ag. Research place). If you're unsure of a name, pick a regional list to get a heap of stations.

Oamaru has no data since 1985. It will be one of many added later as an EWS in due course, I'm sure. (Note: its old 1929-1953 town records have been dropped - I'm not surprised, as they were a bit dodgy. Either that or they've never entered them into the new databases. (See also my comment on old In'gill sun records on Weatherzone!)

Whangarei - probabaly another on the EWS queue. No data since 1993 (note - the values there post-1987 are decidedly fishy).

A new station at Whakatane opened this year to resume sun data - probably electronic I think.

A lot of people are unaware of the N Plym. values. It has topped the country on a number of occasions. High recent values include 229 in 8/2006, 269 in 2/2007. Remember my "looking back" for July 1973?

Nelson and Blenheim will never really match Sydney - will always be 150-200 hrs short. Not bad for temperate maritime though!

Are your Bluff, TP and In'gill averages over the same periods?
Thanks for that Rwood. True that Nelson/Blenheim will never match that of Sydney's but there have been some occasions when their annual total has exceeded that of ours. Another thing is Nelson/Blenheim experiences monthly totals of over 300 hours far more frequently than Sydney does.

Haven't downloaded the averages yet for the SC of Southland, I was referring to actual annual data, Bluff/Tiwai Point has recorded less rain than Invercargill in quite a number of years, i.e the annual total of under 1000mm was experienced more frequently in Bluff and to a lesser extent at Tiwai Point compared to Invercargill. I think Bluff has the added advantage of the "Hill" which can sometimes provide shelter from showery S-SW winds but not by that much, I spoke to some locals and they all seemed to say one thing in common which was that the "Hill" deflected the showers around Bluff on both sides, so Invercargill would get more showers than Bluff - it seems to be part of Bluff's "weather" folklore.

I looked at Google Maps of Oamaru to try and pinpoint the location of Iona Hospital, I have been to Oamaru twice years ago and remember it as a old and quiet town with many lovely old buildings, wide streets (Thames street for example) and the locals were quite friendly, I noticed that many street names are named after UK rivers such as Ouse, Ribble, Nen etc, some of the names are really endearing and difficult to pronounce such as Aln, Alt, Og, Exe, Caen etc, this feature is quite common in Southland such as Bluff where streets are named mainly after Irish rivers and Invercargill Scottish ones. Looking at Oamaru's rainfall data - rainfall is very low indeed which is quite surprising considering that Oamaru is located right on the coast with Christchurch, Timaru and Dunedin recording more.

Invercargill's sunshine hours from 1913 -1931 seems ok to me albeit with many gaps in between, the data for those years seem to correlate ok with post 1932 data.
RWood
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Re: National Climate Database open for free access! :)

Unread post by RWood »

janewaystv wrote:

Thanks for that Rwood. True that Nelson/Blenheim will never match that of Sydney's but there have been some occasions when their annual total has exceeded that of ours. Another thing is Nelson/Blenheim experiences monthly totals of over 300 hours far more frequently than Sydney does.

Haven't downloaded the averages yet for the SC of Southland, I was referring to actual annual data, Bluff/Tiwai Point has recorded less rain than Invercargill in quite a number of years, i.e the annual total of under 1000mm was experienced more frequently in Bluff and to a lesser extent at Tiwai Point compared to Invercargill. I think Bluff has the added advantage of the "Hill" which can sometimes provide shelter from showery S-SW winds but not by that much, I spoke to some locals and they all seemed to say one thing in common which was that the "Hill" deflected the showers around Bluff on both sides, so Invercargill would get more showers than Bluff - it seems to be part of Bluff's "weather" folklore.

I looked at Google Maps of Oamaru to try and pinpoint the location of Iona Hospital, I have been to Oamaru twice years ago and remember it as a old and quiet town with many lovely old buildings, wide streets (Thames street for example) and the locals were quite friendly, I noticed that many street names are named after UK rivers such as Ouse, Ribble, Nen etc, some of the names are really endearing and difficult to pronounce such as Aln, Alt, Og, Exe, Caen etc, this feature is quite common in Southland such as Bluff where streets are named mainly after Irish rivers and Invercargill Scottish ones. Looking at Oamaru's rainfall data - rainfall is very low indeed which is quite surprising considering that Oamaru is located right on the coast with Christchurch, Timaru and Dunedin recording more.

Invercargill's sunshine hours from 1913 -1931 seems ok to me albeit with many gaps in between, the data for those years seem to correlate ok with post 1932 data
.
1. Sydney: remember it's much closer to the equator than N/B, so its daylengths are shorter in summer. If you converted the totals to % of daylight you'd find that 300 hrs at Nelson or Blenheim is less impressive than 300 hrs at Sydney. Also, Sydney's brightest months are not the ones with the longest days.

2. I'm still downloading a set of rainfall averages for Southland stations (will probably do all available stations in NZ in due course). So far all those coastal ones in that part of the south seem pretty close to 1050mm-1125mm. When you get far enough west towards Fiordland the totals go up. They also go up in the hill country in the far SE (Tautuku etc).

3. Oamaru's values are quite low (watch for 71-00 updates if any however as the 61-90 was probably lower). Timaru #2 averages only about 550 so there's not too much in it I think. Will know better after all stations loaded. My 61-90 printed averages cite only top-reliability records, and have no data for Oamaru sites. Temuka values are fairly low.

4. There are some very low values in the old In'gill record that I wouldn't trust much - I think the site was a bit inconsistent for exposure. Values like a 74 for March and 100 for November (can't recall the others) are very doubtful. I seem to recall they didn't compare well with Dunedin values for those months. It's generally true of very old (pre-1930) data that not too much verification was done, as I understand it.
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Re: National Climate Database open for free access! :)

Unread post by janewaystv »

My answers are in Bold.

Sydney: remember it's much closer to the equator than N/B, so its daylengths are shorter in summer.
Yes but not by a very big margin, Sydney can get up to nearly 14 hrs of sun per day.

If you converted the totals to % of daylight you'd find that 300 hrs at Nelson or Blenheim is less impressive than 300 hrs at Sydney.
I can see that point of view, but its still impressive IMO. Sydney has exceeded 300 hours only nine times in the last 31 years at the airport. Ob Hill has not once exceeded 300 hours.

Also, Sydney's brightest months are not the ones with the longest days.
Are you talking in terms of percentage of daylight? Even so August - January on average has over seven hrs of sun per day with the remaining months recording between 5 - 6 hrs per day.

There are some very low values in the old In'gill record that I wouldn't trust much - I think the site was a bit inconsistent for exposure. Values like a 74 for March and 100 for November (can't recall the others) are very doubtful. I seem to recall they didn't compare well with Dunedin values for those months. It's generally true of very old (pre-1930) data that not too much verification was done, as I understand it.
I was inclined to think the same but upon further checking, I came across the figures as described below and I think they do somewhat support those “low values”.
The 74 hrs for March 1915 sounds reasonable because other March’s such as 1968 (92hrs) hrs and 1983 (84 hrs) seem to verify that totals under 100 hrs can be expected but somewhat very rarely. A quick check of March 1915’s weather summary describes that it was a very unsettled and dull month with E-SE winds prevailing with some W weather from the 6th to 11th and the 27th to the end of the month.

A quick check of November 1925’s weather summary describes the month as being wet, windy and cold with frequent & intense westerly disturbances prevailing with the longest spell of anticyclonic weather prevailing on 4 days from the 20th so I would think this seems to verify the 100 hours for November 1925.

Dunedin is 215kms NE from Invercargill so IMO I wouldn’t correlate those 2 together too frequently despite that those two places can share similar totals for a same month or year, some months (I have put down 3 examples) have seen large differences between the two such as January 1939 (DUD with 227 hrs and IVC with 173 hrs), November 1952 (DUD with 147 hrs and IVC with 182 hrs) and March 1983 (DUD with 124 hrs or 112 hrs and IVC with 84 hrs).
RWood
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Re: National Climate Database open for free access! :)

Unread post by RWood »

janewaystv wrote:My answers are in Bold.

Sydney: remember it's much closer to the equator than N/B, so its daylengths are shorter in summer.
Yes but not by a very big margin, Sydney can get up to nearly 14 hrs of sun per day.

If you converted the totals to % of daylight you'd find that 300 hrs at Nelson or Blenheim is less impressive than 300 hrs at Sydney.
I can see that point of view, but its still impressive IMO. Sydney has exceeded 300 hours only nine times in the last 31 years at the airport. Ob Hill has not once exceeded 300 hours.

Also, Sydney's brightest months are not the ones with the longest days.
Are you talking in terms of percentage of daylight? Even so August - January on average has over seven hrs of sun per day with the remaining months recording between 5 - 6 hrs per day.

There are some very low values in the old In'gill record that I wouldn't trust much - I think the site was a bit inconsistent for exposure. Values like a 74 for March and 100 for November (can't recall the others) are very doubtful. I seem to recall they didn't compare well with Dunedin values for those months. It's generally true of very old (pre-1930) data that not too much verification was done, as I understand it.
I was inclined to think the same but upon further checking, I came across the figures as described below and I think they do somewhat support those “low values”.
The 74 hrs for March 1915 sounds reasonable because other March’s such as 1968 (92hrs) hrs and 1983 (84 hrs) seem to verify that totals under 100 hrs can be expected but somewhat very rarely. A quick check of March 1915’s weather summary describes that it was a very unsettled and dull month with E-SE winds prevailing with some W weather from the 6th to 11th and the 27th to the end of the month.

A quick check of November 1925’s weather summary describes the month as being wet, windy and cold with frequent & intense westerly disturbances prevailing with the longest spell of anticyclonic weather prevailing on 4 days from the 20th so I would think this seems to verify the 100 hours for November 1925.

Dunedin is 215kms NE from Invercargill so IMO I wouldn’t correlate those 2 together too frequently despite that those two places can share similar totals for a same month or year, some months (I have put down 3 examples) have seen large differences between the two such as January 1939 (DUD with 227 hrs and IVC with 173 hrs), November 1952 (DUD with 147 hrs and IVC with 182 hrs) and March 1983 (DUD with 124 hrs or 112 hrs and IVC with 84 hrs).
OK - let's look at Sydney Airport. If you take the same basis for % possible calculation as used in NZ, we get roughly these numbers for Blenheim (Nelson is very similar) and Sydney Aero (average % possible sun, monthly and annual)


SYD - 55 56 58 63 61 65 68 75 69 63 58 57 - annual a little under 62.
BLEN - 60 61 59 60 59 59 58 58 57 58 57 55 - annual a little over 58.

This makes it clear that the relatively brightest 4 months at SYD have a much higher average % possible than BLEN (or any NZ site) gets in any month. Sydney's relative lack of very high summer totals reflects partly its regime which has the relatively brightest months when daylengths are not all that long. If SYD's "shape" was the same as Perth's (scaled down to the SYD annual total) then totals of over 300 would be more common. The converse of all this is that 200+ totals of sunshine in May-August (and particularly so in June-July) are rare in NZ - not so in Sydney.

For Sydney OB. Hill, of course its averages are much more comparable to those of Nelson and Blenheim, but the 300+ point still applies.

But as I said - the Nelson & Blenheim values are very good considering the latitude and lack of "continentality".

Invercargill: I've seen old notes about the site that certainly state that there were observational issues near the end of its life, at least.

But setting that aside, the Nov 1925 might be OK. - but a variety of similarly unpleasant Novembers has never produced a total less than 129 at the Airport site. Also, the Dunedin total for the month was 155. So the In'gill total was only 66% of the Dunedin one - for the "new" site, that ratio has never been less than about 76% for any of the months Oct-March inclusive. The E-SE profile for March 1915 doesn't really accord with a low value at Invercargill (Dunedin would be different). If it were westerly dominated I think it would be more plausible. And Dunedin recorded 125 hrs for that month.

My overall impression is that the site was probably inferior, certainly in its later years, and that those 2 totals at least are pretty dubious regardless. Something to ponder.

One thing is certain: the June 1919 total quoted as 173.8 is clearly a typo. I'm sure that value was never in the old paper reports.
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Re: National Climate Database open for free access! :)

Unread post by janewaystv »

OK - let's look at Sydney Airport. If you take the same basis for % possible calculation as used in NZ, we get roughly these numbers for Blenheim (Nelson is very similar) and Sydney Aero (average % possible sun, monthly and annual)


SYD - 55 56 58 63 61 65 68 75 69 63 58 57 - annual a little under 62.
BLEN - 60 61 59 60 59 59 58 58 57 58 57 55 - annual a little over 58.

This makes it clear that the relatively brightest 4 months at SYD have a much higher average % possible than BLEN (or any NZ site) gets in any month. Sydney's relative lack of very high summer totals reflects partly its regime which has the relatively brightest months when daylengths are not all that long. If SYD's "shape" was the same as Perth's (scaled down to the SYD annual total) then totals of over 300 would be more common. The converse of all this is that 200+ totals of sunshine in May-August (and particularly so in June-July) are rare in NZ - not so in Sydney.

For Sydney OB. Hill, of course its averages are much more comparable to those of Nelson and Blenheim, but the 300+ point still applies.

But as I said - the Nelson & Blenheim values are very good considering the latitude and lack of "continentality".

Hmmm yes I can see the point more clearly now, I have just one question to ask you - how does one go around converting actual monthly totals into % of the possible monthly average? Giving me an simple example will do me fine because I have tried on numerous ocassions and failed miserably *embrassed*, interesting to see that Sydney gets the highest % of sunshine possible from the period June to September (over 65% which to me means that any nurses or doctors under the command of middlle agied or elderly folk possible maximum level) with August having the highest maximum % of possible sunshine (75%) which to which I mentioned in an earlier post that August to January has the highest average of sunshine per day which is over 7 hours. Also Brisbane in SE QLD and Darwin in the NT records quite high sunshine totals especially so in the NT where it is usually hot and dry during the winter and more so during the spring period and the total opposite during the "summer".

On the other hand Blenheim & Nelson have far more higher summer sunshine totals than Sydney although as I mentioned before there will be a spell every now and then when Sydney (mostly in the grasp of an El Nino Spell) exceeds that of Nelson & Blenheim but not too somewhat frequently but of course you know that already.

Ob Hill started recording from April 1992 so we are very confused about where & when we should go............


Invercargill: I've seen old notes about the site that certainly state that there were observational issues near the end of its life, at least.

But setting that aside, the Nov 1925 might be OK. - but a variety of similarly unpleasant Novembers has never produced a total less than 129 at the Airport site. Also, the Dunedin total for the month was 155. So the In'gill total was only 66% of the Dunedin one - for the "new" site, that ratio has never been less than about 76% for any of the months Oct-March inclusive. The E-SE profile for March 1915 doesn't really accord with a low value at Invercargill (Dunedin would be different). If it were westerly dominated I think it would be more plausible. And Dunedin recorded 125 hrs for that month.

My overall impression is that the site was probably inferior, certainly in its later years, and that those 2 totals at least are pretty dubious regardless. Something to ponder.

One thing is certain: the June 1919 total quoted as 173.8 is clearly a typo. I'm sure th
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Unread post by RWood »

Rainfan, I think you may have intended to add some words at the end, but anyway I can talk about the % of possible estimation. In the NZ versions the published calculations did the following for each month for the Campbell-Stokes equipment used exclusively until recently: Take the astronomical daylength, subtract 0.5 hrs/day for "attenuation" of sunlight (when it is considered the suncards won't get marked at the very earliest and latest parts of the daylight), and if necessary subtract an estimate of any further losses due to horizon obstruction. Using those totals as the possibles, calculate the ratios of means to possibles to get the %ages.

In the Aust. case I think you'd have to ask local BOM offices as to whether any "attenuation" adjustment is needed, and what if any losses occur due to obstructions. The numbers I quoted you above for Sydney used a 0.5 hr/day subtraction, in the absence of any other information known to me. It depends on how the sunshine was measured, at least.

Meanwhile, here is a table from a Met. Service publication showing for various southern hemsiphere latitudes, the astronomical daylengths with the 0.5 hrs/day subtracted in all cases [easy to recalculate with the 0.5/day restored of course]. The Feb.values are for 28-day Februaries. For latitudes in between the ones given, a simple proportional interpolation will give you good enough answers, at least for Australian latitudes, and avoid the need to look up astronomical tables.

Lat 0: 360 325 360 348 360 348 360 360 348 360 348 360
Lat 5: 368 330 361 345 353 340 353 355 347 363 355 369
Lat 10: 376 334 361 341 346 332 344 350 346 366 362 378
Lat 15: 385 339 362 338 338 323 336 345 345 369 369 387
Lat 20: 394 343 363 334 331 313 327 339 344 373 376 397
Lat 25: 403 349 364 330 322 303 318 333 342 377 384 408
Lat 30: 414 354 365 326 314 292 308 327 342 381 393 420
Lat 35: 425 361 366 321 304 280 296 320 341 386 403 433
Lat 40: 439 368 368 316 292 266 283 312 339 391 414 448
Lat 45: 455 377 370 310 279 250 268 303 338 398 428 466
Lat 50: 475 387 372 303 263 229 249 292 336 405 443 489
janewaystv
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Re: National Climate Database open for free access! :)

Unread post by janewaystv »

Hmm I see that “wifey” decided to be naughty whilst I was answering the call of nature and inserted the “doctor and nurse & middle aged” & “we are confused and where we should go” comments to embarrass me, the fact that she had 2 bottles of wine may have contributed largely….. I didn’t even notice that part when previewing & I seem to have forgotten to edit/finish it off, but I was also very tired and when I am very tired my eyes don’t work well - I all but have to hold them open with matchsticks :lol:

I will have to rephrase/edit this post & have sternly told wifey to stay away this time :evil:

Hmmm yes I can see the point more clearly now, I have just one question to ask you - how does one go around converting actual monthly totals into % of the possible monthly average? Giving me an simple example will do me fine because I have tried on numerous occasions and failed miserably , interesting to see that Sydney gets the highest % of possible sunshine for the June to September period (The benchmark for me is 65% +) with August having the highest maximum % of possible sunshine (75%).

As I mentioned in an earlier post that August to January has the highest average of sunshine per day which is over 7 hours but when you factor in the % of daylight for Nov-Jan - the totals are quite low indeed as compared to the June - September period.

Darwin in the NT records their maximum % of daylight/sunshine quite frequently during the “Dry” and Perth during the summer.

On the other hand Blenheim & Nelson have far more higher summer sunshine totals than Sydney although as I mentioned before there will be a spell every now and then when Sydney (mostly in the grasp of an El Nino spell) exceeds that of Nelson & Blenheim but not too somewhat frequently but of course you already know that, but when you factor in the % of daylight then N/B totals compared to Sydney is lower.

I mentioned that Ob Hill started recording sun from 1992 - (this part was not finished/edited & with the silly last comment from “wifey”) - what I meant to say was that in the M2 bulletin - sunshine hours were used from Ob Hill until 1992, then figures from the airport were used (and still is nowadays). The change of sites is because of obstructions from tall buildings in the city which particularly in latter years had an effect on sunshine hours .
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Re: National Climate Database open for free access! :)

Unread post by janewaystv »

[/quote] Invercargill: I've seen old notes about the site that certainly state that there were observational issues near the end of its life, at least.

But setting that aside, the Nov 1925 might be OK. - but a variety of similarly unpleasant Novembers has never produced a total less than 129 at the Airport site. Also, the Dunedin total for the month was 155. So the In'gill total was only 66% of the Dunedin one - for the "new" site, that ratio has never been less than about 76% for any of the months Oct-March inclusive. The E-SE profile for March 1915 doesn't really accord with a low value at Invercargill (Dunedin would be different). If it were westerly dominated I think it would be more plausible. And Dunedin recorded 125 hrs for that month.

My overall impression is that the site was probably inferior, certainly in its later years, and that those 2 totals at least are pretty dubious regardless. Something to ponder.

One thing is certain: the June 1919 total quoted as 173.8 is clearly a typo. I'm sure that value was never in the old paper reports.[/quote]

Right I see, re November's sunshine total - yes you could be right, but i think its something we'll have to ponder for a long time unless one of us can ask NIWA about this.

I can see the June error, I think it should be reading as 73.8 hrs as we both know there (unless by a very huge miracle) is no way Invercargill can record 173 hrs for a June.

February 1919 (85 hrs) and 1926 (89 hrs) are pretty dubious too, because not once at the Aero has a Feb. total of below 100 hrs been recorded.

Now I dont know if you have noticed but take a closer look at the sunshine totals for sites 5812 and 5814 - those from 1932 to 1951 show the same hours althought from different sites, is this in error? & the city site didn't record any more sunshine since the move to the Aero in 1932.

Where is Arapito? I cant find it on the map, is that in Westland?
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