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Agreed. And if I can make a plea to anyone who wants to comment on this thread -- please make your comment without using the words "capitalism" or "socialism" since neither word has a proper, consensus definition. Using those words will just lead to tedious flamewars with people talking past each other and rehashing old debates. Rather, talk about the underlying structure of incentives that create this dynamic, and how incentives can be changed, if they can be at all.


please make your comment without using the words "capitalism" or "socialism" since neither word has a proper, consensus definition.

This can not be repeated enough. It is absolutely true, if you use the words 'socialism' or 'capitalism' no one will have a clue what you are talking about.


The problem with these discussions is that people usually mean "neoliberalism" when they're talking about capitalism, and "social democracy" when they're talking about "socialism". It's almost as if we never really broke out of the old Cold War terminology and paradigms.


You can add "freedom" and "entitled" to the list of words that are so poorly defined as to be useless for reasoned discussion.


Nowhere in the article does it say what the actual rate of rising is. That seems like important information to omit. Anybody know what it is?


"In the 19th century, as the Industrial Revolution took hold, the ocean began to rise briskly, climbing about eight inches since 1880."

"The sea is rising at what appears to be an accelerating pace, lately reaching a rate of about a foot per century."

"That body [The Intergovernmental Panel on Climate Change] found that continued high emissions might produce a rise in the sea of 1.7 to 3.2 feet over the 21st century."

It's all in there. Towards the bottom, so if you just skimmed you may miss it.


Yes, but what is the delta? Since we are coming out of an ice age a mere 12,000 years ago, we should expect sea level rising. The issue is how much extra sea level rise are we seeing due to anthropomorphic climate change.

I seem to remember from the first IPCC report that it was on the order of a few centimeters per century, which is why I am not greatly concerned about this. But I could be wrong.


>Since we are coming out of an ice age a mere 12,000 years ago, we should expect sea level rising.

Given that the headline is that the rate is higher than the last 2800 years, I'm not sure why you would think that the change that started 12,000 years ago is going to be a significant factor.

The IPCC summary for policymakers [1] has highlevel quick facts, from that:

>Proxy and instrumental sea level data indicate a transition in the late 19th to the early 20th century from relatively low mean rates of rise over the previous two millennia to higher rates of rise (high con dence). It is likely that the rate of global mean sea level rise has continued to increase since the early 20th century. {3.7, 5.6, 13.2}

>I seem to remember from the first IPCC report that it was on the order of a few centimeters per century

Sure, that's the currently observed rate; about 3.2 mm/year +/- 0.4 mm/year, from Table 13.1 of IPCC AR 5. [1]

Of course nobody's really concerned about 3.2 cm in a century. The problem is when that increases by a couple orders of magnitude due to increased warming, which it will unless we stop forcing the climate with additional CO2 within the next 30-50 years.

[1] http://www.climatechange2013.org/images/report/WG1AR5_SPM_FI...

[2] http://imgur.com/vadnlXJ


> Of course nobody's really concerned about 3.2 cm in a century.

You mean 32cm in a century at the current rate of 3.2mm/year. I think people are concerned about even that number, although the real value is likely to be significantly higher.


I'm still trying to understand:

I know, CO2 is a greenhouse gas: So, light from the sun warms the surface of earth which, then, from Planck black body radiation, radiates more infrared light. As we can see from our exhaled breath, CO2 is invisible, that is, does not absorb visible light. But CO2 does absorb light in three narrow bands in the infrared, one band for each of bending, twisting, and stretching of the molecule. So, thus absorbing infrared, CO2 gets warmer and warms the atmosphere and is a greenhouse gas.

I've looked a little on the Internet for details of the absorption spectra of CO2 and how to calculate the rates as a function of concentration, temperature, distance, pressure, etc. Anyone know how to get such background info?

That is, something like in a greenhouse, CO2 lets the visible light from the sun through to the ground but traps some of the infrared light from the ground that otherwise would escape to space.

Maybe since the Little Ice Age, the oceans are still warming up?

Maybe the sea level rise is due to the water expanding due to being warmer?

Maybe the recent increases in CO2 concentration in the atmosphere are from CO2 from the warmer oceans and the point that cooler water absorbs more CO2 and warmer water absorbs less and, thus, releases CO2?

During the Little Ice Age, as civilization grew and developed, likely the rate of CO2 from human activity was increasing, but, then, maybe the significantly lower temperatures of the Little Ice Age were due not to less CO2 from human activity but from less solar activity, e.g., in terms of sun spots, the Maunder Minimum?

Maybe going back to the Medieval Warming Period, the higher temperatures, IIRC, higher than now, e.g., growing grapes in England, have agriculture boom and wealth and cathedral construction increase, were due not to more CO2 from human activity or more CO2 at all but from more solar activity, i.e., sun spots?

Maybe the higher temperatures since the end of the Little Ice Age have been due to more solar activity? E.g., from about 1940 to 1970, the CO2 from human activity was increasing but the level of solar activity was decreasing and, also, the temperature was decreasing. So, more CO2 from human activity but lower temperatures?

Maybe the last 15 years or so of increasing CO2 from human activity but relatively stable temperatures have been from less solar activity?

Maybe the temperature changes are driven more by changes in the level of solar activity than by the changes in the levels of CO2 from human activity or the levels of CO2 in the atmosphere from CO2 released from warmer oceans, from volcanoes, from rotting plants, etc.?

Trying to make sense out of all of this:

Effect of solar activity? More solar activity means more sun spots and, thus, more solar wind blowing past earth. But, there are claims that one of the main sources of cloud formation on earth is cosmic rays hitting water molecules and, thus, stimulating the formation of water droplets and, thus, clouds. But supposedly more clouds have a net cooling effect, maybe from clouds reflecting more sunlight? So, more cosmic rays hitting the atmosphere would have a net cooling effect.

But there are claims that more solar wind blocks some of the cosmic rays, thus, reduces cloud formation, and has a net warming effect.

So, if believe this chain of causes, then more solar activity means more sun spots, more solar wind, fewer cosmic rays hitting water molecules, less formation of water droplets, less cloud formation, and net warming. Any good sources of evidence for such a causal chain? Anyone debunk such stuff? Anyone believe such stuff?


Human emissions levels were very low in the Little Ice Age, compared to today. The only proto-industrialized part of the world was Europe, and Braudel estimated that Europe had access to 1.5-2.5 million horsepower total from all machinery (including wind- and water-power). That's roughly 2 gigawatts of power; we might guess that burning fuel for heat produced about the same order of magnitude. (Fuel was very expensive as late as the 1930s; Orwell has some interesting statistics in _The Road to Wiglan Pier_.) Double that is probably enough to account for the rest of the world: not more than 10 gigawatts of human-generated power and heat, some fraction of it from wind and water. 10 gigawatts is probably too large.

Today, the United States apparently consumes about 2,000 gigawatts (2 terawatts) of power from power plants, and another 2 from all other sources; Europe, China, and the rest of the world probably consume another 2-4 terawatts apiece, for close to a petawatt total -- about 100,000 times the power output of the world in the Little Ice Age.

I don't rule out the possibility that human emissions are having no effect or a limited effect -- or that their effect is positive, by keeping the Little Ice Age from developing into the real thing -- but I'm also not ruling out that the prophets of doom might be on to something. (Jeremiah was simply correct, after all.)

I'm hoping that emissions-cap negotiations get somewhere, and that we see more use of alternative energy (especially nuclear and geothermal), more artificial and biological carbon sequestration, more hybrid and electric cars (and is it too much to wish for, to hope that we see more commuter rail?), and general efforts to keep things from getting out of hand. We don't know what happens next, after all, and we only have to get it wrong once.

Besides, if these sorts of things start producing hazardous levels of global cooling in 50 years, we can just scale them back, or even remove some filters from remaining coal-fired plants. This sort of effort will be expensive, but I'd rather risk doing more than we need to than not doing enough...


Here's a related question: Supposedly now the CO2 concentration is about 400 parts per million (maybe by weight) and up from ballpark 200.

Okay, how much CO2 is 200 parts per million in the atmosphere? Then, how does that much CO2 compare with what comes from human activity? Or, over a time interval while CO2 concentration increases by, say, 1 part per million, how much CO2 was generated during that time interval?

Why?

(1) The atmosphere is a biggie thing, and maybe CO2 from human activity is tiny in comparison, too small to represent increasing CO2 concentration by 200 parts per million. Need some numbers to know.

(2)There are claims that CO2 emitted into the atmosphere by human activity is tiny compared with that from volcanoes and rotting vegetation. If so, then we have to ask where the CO2 for the increased concentration is coming from? From the oceans as they slowly warm from the cooling of the Little Ice Age?

My point about the cooling of the Little Ice Age was that it was likely not caused by reductions in CO2 from human activity. Indeed, as the climate cooled, humans had one heck of an incentive to burn all the firewood they could find. So, the Little Ice Age seems to be a case where there was drop in temperature without a drop in CO2 from human activity. If so, then there have to be some causes of temperature change other than changes in the rate of CO2 emissions from human activity. That is, apparently there would be climate change even without humans.


So I am a little confused.

The title and premise of the article is that we now have news that the oceans are rising at the fastest rate over the last 2,800 years. Is the specific news event a) that the rate last year was the highest ever or b) that scientists have better calculations of the rate of rise for the last century, and these new calculations show the rise is faster than previously believed. I assumed (a), which was why I was looking in the article for what the actual rare of increase was for last year. When the article says, "lately reaching a rate of about a foot per century" is that based on recording the rise over the last century? Or is that based on multiplying last year's rise by 100?

I'm also curious -- how do we know, within plus or minus a foot -- what the sea level changes were in centuries that happened millennia ago?


1.8 to 3 millimeters a year from 25 years of satellite sea surface laser altimetry. Its not an easily obtained number because you have to account for the "noise" of much larger waves, seafloor topography gravitational distortion, multiple satellite generations, and other phenomena. But its is considered a more accurate number than local tidal gauge measurements, which is subject to local interference causes like subsidence.

I do not know if any paper has claimed an observable acceleration or deceleration of this rate yet.


Well oddly the other day NASA claimed that the climate change is also slowing down the rise that should have occurred because 3.2 trillion gallons have been soaked up by parched continents.

too be honest I am not sure who to believe and when anymore. Why do they always ratchet this stuff during US election cycles?

Still being in an interglacial time period we should expect warming, perhaps we are helping it along but cooling would likely be more devastating than warming. The odd thing about reading about glacier melt and such is that the effects are greater on your shoreline the further you are away from the affected glacier.

http://nautil.us/issue/33/attraction/why-our-intuition-about...

That linked article just leaves me in the dust at times, the connections made are just making me rethink how it all works. That we can look back at Roman actions and see that a lot of increase is recent is really cool.


A couple of points.

(1) I work with the lead author of the study you mention (http://science.sciencemag.org/content/351/6274/699.full). It is absurd to say that the timing of his work has to do with the election cycle. He's been working on establishing the size of the groundwater component of hydrological mass balance for at least the past year. I believe the take-away from that article is that groundwater storage has to be taken into account in the next IPCC report, or else we will see missing water and we won't know why.

(2) The study you cite found that some water, that would have otherwise appeared as a sea level rise, is being sequestered as groundwater. The study in the OP said that sea level rise is higher than expected, apparently due to anthropogenic warming. These do not conflict, it's just further information about what's going on. Note also that the OP vs. the article you cite have vastly different time scales (millennia vs. decade) and consequently different precision (cm vs mm).

(3) These studies show we're learning more, because we have a lot of new observational capabilities now (like GRACE, which for the first time measures groundwater mass by its effect on Earth's gravity field). We'll continue to see new studies that establish the sizes of the dominant mass flows as we're able to learn more.


The IPCC assessment reports[1] are really well researched and comprehensive reports of the current science, including measures of confidence in plain language. They aren't hard to read, and there's any number of summaries available, including on Wikipedia[2]. It's a great place to start (and, for most non-climate-scientists, end) your research.

If you (general 'you', not you specifically, parent) want to dismiss an aggregate report of almost all climate scientists across the planet who research this stuff day in and day out as political theater, then I suggest your view of reality may be skewed by some other factor. Science provides us with data as near to facts as it's possible to get; it's up to us how to interpret those facts.

[1] http://www.ipcc.ch/report/ar5/index.shtml

[2] https://en.wikipedia.org/wiki/IPCC_Fifth_Assessment_Report


"Science provides us with data as near to facts as it's possible to get; it's up to us how to interpret those facts."

What is your definition of the word "science" in this sentence? Seems an odd use of the word. "Science" does not provide us with data. Particular people and institutions provide us with data. Furthermore when it comes to climatology, the data is hardly clear cut. All the results and predictions you read about in the paper are based on, as the article says "elaborate statistical techniques." When I hear that, my alarm bells go off. Using "elaborate statistical techniques" one can prove pretty much whatever one wants to prove.


I disagree with your use of "prove" when you wrote

Using "elaborate statistical techniques" one can prove pretty much whatever one wants to prove.

One may be able to massage data and create a nice looking chart to give an incorrect impression to unsuspecting people. This does not constitute a proof and it certainly won't pass muster with others who look at the same data and do their own statistical analyses.


"prove" should have been in scare quotes.


Sure, but he point I made still stands. You can't pull shenanigans with the data when other experts look at it as well.


I agree that my words were poorly phrased. I wanted to communicate that the IPCC report is really the best information we have, and an incredible amount of effort went into ensuring the information in the report is solid.

> one can prove pretty much whatever one wants to prove

Yes, but everyone knows this and this has been gone over again and again and everyone who studies this stuff and understands the science agrees with the report. This isn't a couple yahoos with a copy of SimEarth, this is almost every single climate scientist on the planet.


0.11 inches per year right now. We have had high precision sea level monitoring satellites up since 1992, and the measured sea level rise has been linear since then.


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