Why are winters so cold in sub-tropical and tropical Australia? (temperatures, rainfall)

[nei]

Originally Posted by ilovemycomputer90

Not sure how accurate this source is, but still interesting nonetheless.

Climate of Australia

Interesting article. So maybe you won't get a bigger ice sheet at all, but smaller?

[ilovemycomputer90]

Originally Posted by nei

Interesting article. So maybe you won't get a bigger ice sheet at all, but smaller?

That sounds about right. My uneducated guess is that Antarctica would get warmer. One would assume southern Australia would get cooler, but I'm not so sure about that. So perhaps Australia wouldn't be an extreme version of Canada afterall. But this is assuming that Australia is in it's current position. The subject is a bit more complicated than I thought.

[Trimac20]

Originally Posted by ricardobrazil

I think it's because Australia it's on a free path to cold coming fom Antartica. If you had something like Andes or Himalaia on its way, probably you'd be warmer.

Weirdly, I think mountain ranges do indeed help to keep the cold away in places like the Southwest US. LA's winter highs of 20C/68F and even warmer inland always seemed peculiarly warm, since a place at a similar latitude in Australia would be closer to 16-17C. Even factoring in the many sunny days it still doesn't add up. The only explanation I can come up with is that mountains somehow shield it from the cold of the interior.

You forget about a little thing called the ocean. The fact we have like 3,000 km of ocean between us and Antarctica means all that Antarctic air really does nothing to cool us down during winter or summer. No, the cooler summers are to do with the strong oceanic influence in the warmer months.

In Australia, heating/cooling isn't really affected by frontal activity so much as the landmass itself heating and cooling. Although polar airmasses can reduce temps in southern Oz, they're so moderated by the ocean they're scarcely polar anymore. The northern outback is too far away for that anyway so it's more a case of extreme high pressure causing extreme diurnal range.

[England East Anglia]

southern hemisphere is always colder than its northern hemisphere counterparts pound for pound , mainly because Antarctica is a lot colder than the Arctic.

[ColdCanadian]

Originally Posted by Trimac20

In Australia, heating/cooling isn't really affected by frontal activity so much as the landmass itself heating and cooling. Although polar airmasses can reduce temps in southern Oz, they're so moderated by the ocean they're scarcely polar anymore. The northern outback is too far away for that anyway so it's more a case of extreme high pressure causing extreme diurnal range.

In Australind,
it feels like a polar front brings a 2-4 C (4-7 F) temp drop,
15+km/h (10mph+) windspeed increase
and a "feels like" temp dropping only as much as 10 C/18 F.

Back in Toronto, polar-anything means a minimum of 7 C/13 F drop in temps alone.

[theunbrainwashed]

Well, I've watched Survivorman with Les Stroud before, and he went to the Outback during the warmer part of the year, and he said that when the sun falls, the temperatures in the Outback drop dramatically and you need to be near a fire to keep warm. Also learned in school, that the same thing happens in the Sahara. The days are hot like hell, and the nights are freezing. It's just the nature of the desert, IMO

[Trimac20]

Originally Posted by theunbrainwashed

Well, I've watched Survivorman with Les Stroud before, and he went to the Outback during the warmer part of the year, and he said that when the sun falls, the temperatures in the Outback drop dramatically and you need to be near a fire to keep warm. Also learned in school, that the same thing happens in the Sahara. The days are hot like hell, and the nights are freezing. It's just the nature of the desert, IMO

Yes and no. That applies during the cooler months, but summer nights in most of the hot deserts of the world are hot. Phoenix in the desert has an average July low of about 26.6C/80F these days, I certainly wouldn't call that cold. Most of the northern Outback has summer minimums of at least 21C/70F, which again would feel distinctly warm for a night, since after a 45C day, for instance, it would still be something like 33-34C at sunset. There are certainly days when it can go from freezing to 30C, but they tend to occur in the Spring or Autumn months. Days where it's very cold at night and very hot in the day do occur but in summer it tends to be always hot, and winter days are generally more warm than very hot.

[theunbrainwashed]

Originally Posted by Trimac20

Yes and no. That applies during the cooler months, but summer nights in most of the hot deserts of the world are hot. Phoenix in the desert has an average July low of about 26.6C/80F these days, I certainly wouldn't call that cold. Most of the northern Outback has summer minimums of at least 21C/70F, which again would feel distinctly warm for a night, since after a 45C day, for instance, it would still be something like 33-34C at sunset. There are certainly days when it can go from freezing to 30C, but they tend to occur in the Spring or Autumn months. Days where it's very cold at night and very hot in the day do occur but in summer it tends to be always hot, and winter days are generally more warm than very hot.

You're right, I forgot to add that I'm talking about the uninhabited parts of the deserts, far from any city. My mistake But, yes you are right. Summer nights are still comfortably warm in the cities

[Trimac20]

Originally Posted by theunbrainwashed

You're right, I forgot to add that I'm talking about the uninhabited parts of the deserts, far from any city. My mistake But, yes you are right. Summer nights are still comfortably warm in the cities

Yeah I wonder where Les Stroud was talking about...the southern deserts like the Great Victoria Desert and the Nullabor (which by rainfall is arid) can get coolish in summer, but even remote parts of the northern deserts remain hot at night. In the Southwest US the heat island effect makes things even worse...I hear it's not uncommon for the mercury to remain above 30C all night long in Phoenix these days.

Death Valley has the highest July minimum of about 30C (86F) in the lower 48 states. I can barely imagine how oppressive that can be. I read somewhere their highest ever minimum there was 39.5C (103F). Similar conditions are found in parts of the Middle East.

But either way, when they say deserts are scorching in the daytime and freezing at night it is a bit misleading.

[nei]

I think just about all hot deserts have warm to hot summer nights. Excluding ones at high latitude (like deserts in Washington State) or high altitude, I can't think of any exceptions.