2004 : it was found that the northern tip of Antartica was growing grass – (hitherto sparse tussocks). Over the summer of 2004, great meadows of the stuff. – Hard to imagine anything more emblematic of transformations at the poles.
The subantarctic seas are rich in plankton and hence krill which grow despite low iron. The presence of sea ice compensates for this. The semi-frozen edge between salt water and floating ice promotes remarkable growth of microscopic plankton that is the base of the food chain. - and hence penguins seals and great whales. The seaice has a massive influence on plankton.
Dr Angus Atkinson et al of British Antarctic Survey examined records of krill … before 1939 it was “stable”, no overall trend. But since 1976, the krill have been in sharp decline, reducing at a rate of nearly 40% per decade. Atkinson sums up “These changes … have profound implications for the Southern Ocean food web. Penguins albatrosses seals and whales … are prone to krill shortages”.
Since 1980s there has been satellite coverage to show the extent of winter sea ice. Prior to that it is stil possible to study the ice and estimate extent. The research reveals the extent of sea ice was stable to 1950, but has decreased sharply since. The northern boundary has shifted southwards from 59.3S to 60.8S (which I believe is about 6 miles). This corresponds to a 20% decrease in sea ice extent.
To gain a sense of magnitude and rate of change involved, imagine what it would mean for the animals of the Serengeti if their grasslands grasslands had been reduced by 40% per decade since 1976. Already there are signs that some Antarctic fauna are already feeling the pinch. The emperor penguin is half what it was 30 years ago, while the number of Adelie penguins has declined by 70%.
Such studies suggest that in the near future a point will be reached where, one after another, krill-dependent species will be unable to feed. If so, the southern right whales that have only recently begun to return to Australia and NZ shores will no longer come. The humpback whales that traverse the world’s oceans likewise will no longer be able to fill their capacious bellies, nor will the innumerable seals and penguins that cavort in southern seas. Instead we’ll have an ocean full of (useless) jelly-like salps, the ultimate inheritors of a defrosted cryosphere.
I don't recall arguing that nuclear (or any other) power plant can't operate at reduced output.btw smurf,
I'm not convinced your theory that nuclear plants cannot be adjusted / powered down for off peak periods ... just as nuclear batteships do for instance.
Just compiling some data to show how it actually worked yesterday. This might take a while as there's LOTS of numbers...smurf, I concede they (nuclear plants) are more expensive / less efficient without hydro in parallel. - Then again if hydro is not feasible, - land just isn't available for instance - then you just have nuclear / stand alone, and/or in conjunction with other cleaner power. (or reduced amount of dirty power)
btw smurf,
I'm not convinced your theory that nuclear plants cannot be adjusted / powered down for off peak periods ... just as nuclear batteships do for instance.
I was thinking of #1033 on "global warming - how valid and serious" thread ;I don't recall arguing that nuclear (or any other) power plant can't operate at reduced output.
Nuclear is certainly viable without hydro. But running a 100% nuclear grid would be incredibly inefficient at best.
The problem relates to demand variation. If you have 13,000 MW at the daily peak and 7500 MW at the daily minimum (rough figures for NSW) then you'll have a lot of trouble doing that all with nuclear.
Nuclear plants run nicely at constant load. Having 13,000 MW running like that would be inefficient technically and financially - lots of wasted heat and a fortune spent building rarely used peaking plant...
gg - not sure how to answer.Would a nuclear plant be a suitable present for her for her birthday which is imminent. Do they need much looking after?
Just to put you out of your misery: Arctic ice is receding overall, and quickly.I believe I've read in recent posts that icecaps (Arctic) are ok - I seem to recall a photo which showed less ice in Gulf of Finland this year, which is consistent to a previous post I'm made (twice I believe) that, due to a 300 year return period event, - absense of sea ice etc - the seal pups born to that date will almost certainly not survive.
Coral :- (apart from pollution ) ….
It’s the direct impact of higher temperatures however, that is proving to be the most threatening aspect of climate change to coral reefs. High temperatures lead to coral bleaching, and to understand that phenomenon we need to examine a reef far from human interference, where warm water alone is causing change. There are thankfully some reefs protected by remoteness and size, with no pollution, fishermen or tourists. Myrmidon Reef, lying off the coast of Qld, sees almost nothing of humans. Every three years, scientists from the Aust Institute of Marine Science in Townsville survey it, and when they did so in 2004, they took along environmental writer James Woodford. He described Myrmidon as looking “as though it’s been bombed”. This was the result of the reef crest being severely bleached, leaving a forest of dead white coral. Only on the deeper slopes did life survive.
RobJust to put you out of your misery: Arctic ice is receding overall, and quickly.
Antarctic sea ice is increasing, firmly.
West Antarctic sheet ice is decreasing, East Antarctic sheet ice may be in balance, or increasing slightly - depends who you read and their methodology.
Trends in Antarctic sea ice are explained by the "buffering' effect of ocean currents that tend to carry warmer waters away from the continent. The opposite is the case in the Arctic.
The meteorological year, December 2007 through November 2008, was the coolest year since 2000, according to the Goddard Institute for Space Studies analysis of surface air temperature measurements.
It was the ninth warmest year in the period of instrumental measurements, which extends back to 1880.
The nine warmest years all occur within the eleven-year period 1998-2008.
which is the same as saying that "rainfall" is increasing in that neck of the woods - big deal.Rob
I'll only concede (at this stage) that snowfalls over the landmass of Antarctica are possibly increasing ...
I believe I've read in recent posts that icecaps (Arctic) are ok - I seem to recall a photo which showed less ice in Gulf of Finland this year, which is consistent to a previous post I'm made (twice I believe) that, due to a 300 year return period event, - absense of sea ice etc - the seal pups born to that date will almost certainly not survive.
Rising temperatures could spell disaster for seals living in the Baltic Sea in northern Europe. An environment group is warning that hundreds of baby seals are now facing a painful death.
"The situation is dramatic," Cathrin Münster, of the WWF's Baltic office, warned Monday in a statement. "It could turn out that not one of the seal babies born in the last few weeks will survive."
Seal mothers usually create deep burrows in the snow to protect their young. With those burrows now melting too early, the young pups are forced into the icy waters before they have built up protective layers of fat. They are also too young to defend themselves against predators like foxes and eagles
According to the WWF, worst affected are seals on the south-west coast of Finland, in the Gulf of Finland and the Gulf of Riga. The region has experienced a winter with the least ice formation for 300 years, according to the German Maritime and Hydrographic Agency.
In a normal winter, the agency says, the Gulf of Bothnia, which lies between Finland and Sweden, is completely covered by ice between the end of February to mid-March. But this winter ice only formed in the northern parts of the gulf and in patches in the south.
According to the WWF, there are only 7,000 to 10,000 seals in the Baltic Sea today, which is why they have been placed on an international list of endangered species. At the start of the 20th century, the group says, there were about 180,000 seals in the area, but hunting and environmental degradation have drastically cut their numbers.
Quadrant Magazine, a conservative journal has some quite good articles over the last few months refuting many of your arguments 2020.
You should give it a read.
Its at most enlightened newsagents and libraries.
There is currently a focus on the state of the Murray-Darling Basin and the condition of the lower Murray River, as if the current low river flows had not happened before. However, during the Federation Drought the basin suffered significant rainfall deficiency and by late 1902 the Darling and Murray Rivers had virtually run dry. ...
Sydney has roughly double the annual rainfall of Hobart...PS you'll note I followed up that post (with #1020 back 20 or so) with more emphasis on efficiency. Still I would argue that what goes for Tasmania sure as heck doesn't apply to most of Australia ( in terms of hydro) - especially with damn all rain in Sydney (or Perth) these days. etc
1. yep, and we need that and some for the population - storage levels trending down etc.1. Sydney has roughly double the annual rainfall of Hobart...
2. In a post-fossil fuel world, changing coal for nuclear is easy enough but what about the load variations handled by gas? That's the load that needs to go to pumped storage if we're to get off fossil fuels.
3. Give us a truly hot day across all states and you'll see a whole lot more gas, hydro and even a bit of oil-fired generation than we did yesterday. That's the issue if we tried to rely totally on nuclear.
4. Even France hasn't sorted that one out - they went to 80% nuclear for the same reasons Victoria historically had 85% brown coal power. Technically it's doable but going to 100% isn't cheap, efficient or easy when you're dealing with these fuel sources.
It's actually been quite sunny here too, on and off, just extraordinarily cold.Good heavens, minus 12!! Quite apart from your obvious point with respect to the argument here, how miserable is that! Sure you don't want to come back to sunny Oz, Wayne?
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