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Comment: Re:Do not want ... (Score 1) 114

by agenaud (#44532387) Attached to: Mozilla Launches Persona Identity Bridge For Gmail
  • Conversation between Alice and Cats.com
    • Alice: Hello Cats.com, I would like to login as alice@gmail
    • Cats.com: Please, provide me proof with nonce 98765
  • Conversation between Alice and Gmail
    • Alice: Hi Gmail, can you verify that I own alice@gmail with nonce 98765
    • Gmail: Certainly, Just login
    • Alice: OK, here's my password
    • Gmail: Here's a signed assertion that alice@gmail logged in and provided the nonce 98765
  • Conversation between Alice and Cats.com
    • Alice: Hi Cats.com, here's Gmail's signed assertion that I logged in and provided nonce 98765
    • Cats.com: Thanks Alice. Now I know that you are the owner of alice@gmail account

Of course the browser is doing most of the work for Alice and the browser can and might be storing all of her details and perhaps Alice asked the browser to keep these details for her convenience.

Comment: Re:More to the point... (Score 1) 437

People are finally starting to get over the 'climate may be changing' thing, a process which has long been delayed by the heavily politicized 'why' question. It's more accurate to think of it in terms of climate changing due to a number of factors, some of which humans are responsible for, than to entirely assign blame one way or another. For one thing, it's not remotely accurate to say that climate change is something humans are totally responsible for; to do so is to ignore natural cyclical fluctuations of that climate.

That is correct. Humans are not totally responsible for climate change, but humans are mostly responsible for temperature rise. Look, it's not rocket science: add greenhouse gases and radiation (sun light) to an environment (like an actual glass greenhouse) and the temperature will rise. We know how much CO2, CH4, and other gases humans are dumping in the air and we have a pretty good idea what effect that will have and is having. This is not disputed by anyone with an advanced degree in chemistry, physics, climate science, nor most horticulturists. There is debate about the precise working of clouds, precipitation, feedback, absorption, etc, but not the general principal. We know that greenhouse gas levels have been moderately constant for 10 000 years and we know that the 50% increase in the past fifty years would not have happened without humans. These are indisputable facts. The greenhouse gasses that humans have added to the atmosphere have brought the Earth to levels not experienced in the past 800 000 years, and very likely not in the past 20 millions years (keep in mind the FA referenced events 5 million years ago), and we keep pumping more and more into the atmosphere!

Comment: Re:Causation or Correlation? (Score 1) 437

Unfortunately your link has nothing to do with glacial periods or ice ages. It only shows an graph of the temperature at antarctica. Also: is it a mean temperature? What is the graph supposed to mean? As it is slightly above zero degrees most of the time, the graphbmakes no sense at all anyway.

We are still in the Quaternary ice age and have been for 2.6 million years. The link most certainly has something to do with glacial periods, at least eight of them, on the order of 100 000 years. On thousand year scales, we can easily deduce ice volume and how much of the Earth is frozen from global average temperature. Ice cores from around the world correlate on decade scales, perfect correlation on 100 000 year scales. The reason Antarctica is more interesting than say Greenland is simply because Antarctica is deepest, oldest, most stable. The temperature is variation from mean. Plus and minus 5 C is quite significant. It's more than the difference between a glacial and interglacial period -- precisely what the graph demonstrates for you.

Comment: Re:Causation or Correlation? (Score 1) 437

Please explain why you are sure that the cessation of the ice age, with an accompanying moderation in temperature, is not what permitted human agriculture -- and not the reverse.

I believe the previous commenter IS proposing that retreating glaciers and moderate temperature DID permit agriculture. Or are you proposing that agriculture, planting seed in snow and ice, caused the cessation of the ice age and moderation in temperature? FYI, we are still in an ice age known as the Quaternary period which began roughly 2.6 million years ago. The glaciation on the order of 100 000 years of which I think you are referring is the Late Pleistocene era. This was a time when Neanderthal, mammoths, and saber-toothed tigers roamed the earth. They died out as glaciers such as those around the Great Lakes and the Baltic retreated and sea level rose 35 meters to roughly its present level. The moderate Holocene period beginning about 11700 years ago through present saw moderate flucatuations +/- 0.5 C (though the temperature rise of the past 150 years is unprecedented in the past 10000). It is possible that modern humans killed off the Neanderthal and megafauna during this Mesolithic age of human technology (ie stone age). Perhaps they caused the global temperatures to rise 2 C in a short period of time around 12000 years ago. A more likely explanation (given that we've actually seen evidence) is that the Earth collided with numerous meteorites. Incidentally, the resultant megatsunamis are a likely explanation for the Noah and Gilgamesh flood myths.

Comment: Re:FUD title (Score 2) 437

We are coming out of a glaciation period (a little ice age if you will) on the order of 100 000 years. Given a fairly predictable periodic pattern we would expect to peak and cool in the next 1500 years leading to another several thousand year glaciation. But due to fossil fuel burning we are likely to skip that glaciation and enter acyclical warming. http://www.bbc.co.uk/news/science-environment-16439807

Comment: Re:More to the point... (Score 1) 437

Why shouldn't Antarctica melt? CO2 concentrations are similar to levels of 15 millions years ago (the article references 5 million years ago) and CO2 levels are accelerating due to increased fossil fuel burning and past accumulation (and methane released from permafrost melt). 15 million years ago temperatures were 5 C warmer than today and the ocean was likely 40 meters higher than today. Antarctica has a massive sheet of ice no doubt but it is melting with no sign of slowing down. If the north pole can be ice free in September (likely within a decade) then Antarctica could be ice free in March (albeit quite a bit more into the future).

Comment: Re:Jesus. Get a grip. (Score 1) 437

IPCC is incredibly conservative. For one thing it doesn't consider methane released from permafrost because the data is new and the cut off for new article submissions was years ago. We're expected to release a minimum of 135 gigatonnes of CO2 equivalent in our lifetime and there is nothing we can do to stop it.

Comment: Re:Who was burning fossil fuels then? (Score 2) 437

You read one article from your armchair and think, "hey good going, look into this"? There's been active research in climate cycles and mass extinction events since the 1800's.

Some causes are the precession, solar output, and meteors as you mention. CO2 and temperature are co-dependent feedback variables. Raise CO2, temperature rises. Raise temperature, CO2 rises. (same in reverse and hense we see a very cyclical 100 000 year pattern). It doesn't matter what triggers it. By all evidence we are on the up slope of the 100 000 year cycle, with or without human interference. But humans are certainly exacerbating the warming through burning.

The article says that when the oceans were 20 meters higher five million years ago the CO2 levels were similar, but in fact CO2 levels were less than the 400 ppm we have today, and levels are sky rocketing (in geologic and human time).

CO2 levels were over 400 ppm 15 million years ago at a time when no humans were alive nor could have survived. Temperatures were 5 C warmer and oceans were 40 meters higher than today. That's the course we are headed toward.

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