Where do you find sunshine hour averages from the BOM? (storm, cyclone)

[nei]

Originally Posted by deneb78

Hobart for example is much warmer than Boston in winter which is at the same latitude.

Well Hobart has a maritime climate so that is to be expected. Hobart's about the same as Rome, Northern Spain and coastal Northern California (Crescent City); which are at similar latitudes to Hobart.

[RWood]

Originally Posted by tom77falcons

BTW, google Stokes-Campbell and enter the term "dry air". It seems that Stokes-Campbell record bright sunshine at 70Watts when conditions are very dry, as in parts of Australia during dry spells.

That doesn't particularly surprise me, and it doesn't invalidate my general comments. I have never claimed superiority for any particular method, just that C-S overall gives significantly lower numbers than either your F-F or the kind of instruments now being introduced in this country. And I still have an issue with the WMO-quoted 85 and the 120 claimed in the article you referred to.

[Joe90]

Originally Posted by tom77falcons

Re-read my post. My friends learned their lesson long ago as kids, just like I did. They use sunscreen early on when it's first warm enough to go to the beach. They don't let themselves get burned now.

Your post doesn't make it that clear, but not to worry, I hear what you're are saying. What I'm trying to get across, is that on a bad day, 20 minutes enjoying a coffee in the sun will burn even tanned people- we have italians here also, and darker skinned people. It's variable however, some days aren't a problem. As I remarked earlier, this summer seems to have a mellow sun so far.

[tom77falcons]

Originally Posted by RWood

That doesn't particularly surprise me, and it doesn't invalidate my general comments. I have never claimed superiority for any particular method, just that C-S overall gives significantly lower numbers than either your F-F or the kind of instruments now being introduced in this country. And I still have an issue with the WMO-quoted 85 and the 120 claimed in the article you referred to.

At NWS sites, the F-F machines were to be calibrated on a regular basis based on what the threshold was. If the sun did not cast a clear shadow, yet the sensor was "on", the sensor was then adjusted. I would think over time sensors would be properly adjusted.

[tom77falcons]

Am curious, I wonder what the diff between 100W/sq m vs say 200W/sq m would feel to the average person walking around. I mean if the S-C went off at 70W/sq m in very dry conditions, and in very humid, clear conditions 280W/sq m that seems quite a diff for the same clear skies, except one has water vapor. I know humid days are hazy, but you still quite strongly feel the sun.

[Trimac20]

Originally Posted by tom77falcons

Something to keep in mind is the quality of the sunshine. Sunshine in winter, even at Sydney's latitude, is poorer in my opinion than sunshine in summer where the sun is blazing down on you from very high in the sky. Sydney is cloudier than almost everywhere in the US in summer. So yes, Sydney has high sunshine hours, but much of that comes at a time when the sun is relatively low in the sky. During summer the % of possible in the low 50's is rather poor.

Quality as in strength? I actually tend to appreciate bright sunshine more in the cooler months than in summer. In summer, if it's too hot, I find it just burns and gives you sunburn. On a nice winter's day in Sydney you can bask in the sun...it's always nice to just sit in the sun at the Rocks or Darling Harbour or something at a cafe and watch the ferries. You can watch the sun glint off the waters of the harbour.

Given the number of cloudy days and raindays, and my impressions of visiting Sydney during different times of the year, it definitely doesn't feel like a gloomy climate, but there is quite a bit of cloud, particularly in the first half of the year. I'd say it's got a perfect balance of sun and cloud cover.

[Trimac20]

Originally Posted by tom77falcons

I think this whole sunshine thing is being overblown. The data in Australia, NZ and elsewhere used a machine that was not foolproof. Human observers filled in the blanks and also read the cards. The US does not count "visible" sunshine either, from what I read.

As far as our sunshine being underwhelming by your standards, maybe that has to do with the ozone being naturally thinner in the S. Hemisphere.

Trust me, some fair haired white skinned Australian sitting on our beaches in summer all day with no sunscreen on will fry. I happen to live in an area of the US with a lot of Italian Americans. I've grown up with these guys and have gone to the beach with them my whole life. In the beginning of summer, even with their olive skin, they will get sunburned if laying on the beach all day without sun screen. Once they get a tan, they don't need as much. And from what I've seen, they look a hell of a lot darker than those 90% of Aussies that hail from the British Isles. But this notion that our sun at latitude 40N is somehow weak, and that NZ's and Aussies can walk around the US all summer with no sunscreen on, c'mon.

I find that bit about the deserts of the US SW hard to believe. I've read quite a few travel blogs of Aussies in the desert SW, and they certainly do go on about the blazing sunshine and the heat.

I think the sun is stronger in Australia because of less pollution and the hole in the ozone layer. I know the UV is worse but in terms of comfort levels I'm not sure. I did find the sky a bit hazy in the NE US during summer, even on clear days, but there were just as many partly cloudy and cloudy days in NY and Boston.

We also have Italians, Greeks etc. We're more like 65-70% from the British Isles than 90%. In many areas the Anglos are outnumbered by others.

I agree though, most people from Northern Europe aren't suited to laying out in the Australian sun ALL DAY long, even WITH protection. I'm not against a tan, but I think you have to strike a balance. Even with my olive skin I will burn a bit/flake if I stay out all day. Sometimes we shouldn't really expect our body to adapt to vastly different climatic conditions than it was designed to.

[Trimac20]

Originally Posted by wavehunter007

Wow – you are quite fascinated in sunshine lad. Perhaps you are solar powered (like me). Seriously, just a few other interesting things to consider in this sunshine issue…which I find as interesting as you do:

1 ) Beyond true desert climates, much of the time sun hrs in more humid climates like Miami, Brisbane, Gold Coast…etc will often some cloud in the sky on a typical day. The BIG DIFFERENCE is that the clouds in these much lower latitudes regions tend to be of the more vertical type (cumulus)….rather than the more horizontal type (stratus). The comment about Miami “feeling” really sunny all the time (Tom 77 above) is well taken: The sun always seems to be on your back/in your face in Miami, in all seasons – yet there is always some tall vertical cumulus clouds in some part of the sky. I would guess (just a guess), that if one was in Miami/ Brisbane on what was termed “a partly cloudy day”….and one was in Seattle/ South Island, New Zealand on what was termed “a partly cloudy day”….I would bet the lower latitude climate would have the look/feel of being "more sunny" due to the arrangement of clouds. Just for example – here is a pic of Ft. Lauderdale; is this a partly cloudy or sunny day?




2) In terms of summer sunshine in Sydney vs cities like NYC or Washington DC… I know two professional woman who moved to Sydney for several years - and have on/off worked and lived inside the Beltway (DC) and Manhattan. The first thing they mentioned in a conversation about Sydney’s climate was that it seemed cloudier in summer than NYC or DC. True, it matters greatly if a cities climate is experiencing anomalous conditions – but this tells me at least Sydney had the potential to seem cloudy compared to NYC or DC.

3) In relation to the very high sun hrs in interior South Carolina (in the general area of Columbia southward) - I have seen papers that in some years 3500 hrs of sun can be logged in this area. Yet, there are environmental/physiographic features to this small sub-region that create the conditions for an unusually high about of sun hrs that might not be apparent at first glance (this goes back to my comment a few pages ago how small micro-conditions can add up to a great deal):

By far the most interesting geographical feature in interior South Carolina is what is known as the “Sand Hills”. The Sand hills is a strip of hilly, unconnected bands of sand left from the ocean dunes during the Miocene Epoch. These sand hills generally divide the Piedmont from the Atlantic coastal plain. Soils in the Sandhills are extremely well drained – often the soil is nothing more than yellow/grayish loamy sand. Because they are predominantly porous, sandy soils tend to be extremely droughty. This is why there is often severe drought in interior South Carolina in some years. Although the peach industry flourishes in this area (peaches need a well drained soil), for the most part heavy irrigation is required for agriculture. The physical environmental in this region reflects the dry conditions, there are few leafy green trees – the landscape is mostly scrub pine, beach sand, and a rather large concentration of snakes (including coral snakes I think).

Climatically, this region is quick to lose moisture, so very often (esp at the time of high sun) there is surface high pressure, clear skies, and very hot temperatures in this region of South Carolina. In terms of solar intensity/sun hrs – all the ingredients seem to come together in this small sub area – a porous surface that looses moisture extremely fast, surface high pressure, and lower latitude. These environmental/geographic features are (in part) thought to be the reason why this interior region of South Carolina tends to be unusually sunny. I’ve trekked though this region a few times – hot, sunny, and dry are understatements. This is pic of the typical look of the Sand Hills in interior South Carolina:



.

Yeah I think a lot of people expect more sun in summer when they are more active outdoors, particularly from a place like the NE US for the window for activities like swimming, going to the beach is mostly limited to 4 months of the year. Sydney actually reminds me of LA in a way, despite the climates being much different (aside from temperature). It feels sort of 'seasonless' because it's often hotter at other times of the year than summer. Like it's not uncommon to experience high 20s or even low 30s in August, and then you might have heavy rain and low 20s in summer. Sydney can indeed feel pretty cloudy in summer, but it is made up by other parts of the year. Much of winter, Spring and early December you can get weeks of clear to mostly clear weather. From my experience anyway. The last time I was in Sydney it was August. I was there for two weeks and it probably rained on only a couple of days. I've been to Sydney in July too and just clear skies.

Coastal Queensland and Florida seem to have many partly cloudy days, although Queensland still gets a decent number of clear days, particularly in winter and early spring.

[RWood]

Originally Posted by Trimac20

Sydney can indeed feel pretty cloudy in summer, but it is made up by other parts of the year. Much of winter, Spring and early December you can get weeks of clear to mostly clear weather. From my experience anyway. The last time I was in Sydney it was August. I was there for two weeks and it probably rained on only a couple of days. I've been to Sydney in July too and just clear skies.

Coastal Queensland and Florida seem to have many partly cloudy days, although Queensland still gets a decent number of clear days, particularly in winter and early spring.

I've done the Sydney monthly sun % values before - but here goes again (based on astronomical daylight - real %ages could be 2-3% higher year round):

53 54 56 61 59 60 65 72 66 61 55 55 year 59.4

[tom77falcons]

Originally Posted by RWood

I've done the Sydney monthly sun % values before - but here goes again (based on astronomical daylight - real %ages could be 2-3% higher year round):

53 54 56 61 59 60 65 72 66 61 55 55 year 59.4

Those winter numbers are amazing, compared to here. I would think with that much sunshine, and temps in the 60'sF, Sydney really has no Winter (IMO).

That to me would be a very sunny Spring here. Also, Autumn certainly looks rather nice as well. 59% annually would actually be better than the 56% we get here.