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rbord
Boulder climber
atlanta
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Sep 12, 2017 - 09:33am PT
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Scientific projections of sea level .. .. quit presenting worst case scenarios as if they're a given.
I think this is a problem in the wider community - that when scientists make predictions or projections based on the information that we have, people misinterpret it and think that they're making statements of fact - givens - about what is going to happen.
And then we break into camps of believers and non believers, because it seems like we need to choose one or the other. What do people like me believe?
Humans seem to have an unshakeable faith in the omniscience and omnipotence and uber-rationality of our (individual) belief processes. For me, even more than climate change, that faith, and our unwillingness (or is it inability? nah, we're omnipotent!) to notice the social component of our belief processes, is the biggest challenge we're facing in our environment.
God is coming - look busy :-)
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monolith
climber
state of being
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Sep 12, 2017 - 10:49am PT
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https://www.scientificamerican.com/article/climate-science-predictions-prove-too-conservative/
Across two decades and thousands of pages of reports, the world's most authoritative voice on climate science has consistently understated the rate and intensity of climate change and the danger those impacts represent, say a growing number of studies on the topic.
Sea-level rise is another. In its 2001 report, the IPCC predicted an annual sea-level rise of less than 2 millimeters per year. But from 1993 through 2006, the oceans actually rose 3.3 millimeters per year, more than 50 percent above that projection.
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rbord
Boulder climber
atlanta
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Sep 12, 2017 - 11:04am PT
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The problem is that you other people are just mental speculators.
You need to be more like me, Magical Me, and just perceive the truth, as I myself have done on countless occasions. For full details, see my published works.
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rbord
Boulder climber
atlanta
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Sep 12, 2017 - 11:18am PT
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Thanks monolith.
I once had a very intelligent, very well respected scientist (who I personally have a lot of respect for) tell me that they expected that the political environment created by Trump's election would influence scientists to under-estimate the effects of global warming in future scientific papers.
But the idea that scientists in the previous political environment might have been influenced to over-estimate the effects of climate change was an insult to their scientific integrity.
For me, that was kind of a head scratcher, but as far as beliefs go, it seemed human enough.
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Splater
climber
Grey Matter
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Sep 12, 2017 - 03:52pm PT
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Your claim of the rate rising to roughly at least 12mm per year by 2060 and that it's the consensus opinion is just alarmist BS.
Your assumptions are contradictory.
We are not talking about best case/lowest case scenarios, which assume the world takes large action to limit GHGs. That would be a scenario such as RCP2.5, which assumes emissions are highly limited very soon.
That is what I suggest we do, but it is not happening now. I am talking about scenarios where we continue to do very little control policy, the same type of non-policy favored by "skeptics" and deniers. This means a scenario such as RCP6.5 or more.
Those scenarios are where models predict .5 to 1 meter of LIKELY sea level rise by 2100. Worst case maximums are 1.5-2 meters.
.8 meter = 800mm in 90 years is 9mm per year Average.
However it's NOT a constant linear increase over time
You have to look at the actual curves. In the early years we're still at 3.5mm per year, well below the average. Measurements so far are not very useful in foretelling us about the large increases due in the future. By 2060 the yearly increase goes to well above the average. So it will likely be Higher than 12mm per year during the out years. (which will continue long past 2100 under our current feeble policy)
The reason sea level rise is not constant is mostly due to the huge time constants of ocean temperature rise and ice melting. It takes many decades for it to reach steady state after just one year's rise in GHGs. And then compound on top of that multiple years of rising GHGs.
see chart on page 5 of http://www.southeastfloridaclimatecompact.org/wp-content/uploads/2015/10/2015-Compact-Unified-Sea-Level-Rise-Projection.pdf
"This [low] scenario would require significant reductions in greenhouse gas emissions in order to be plausible and does not reflect current emissions trends."
https://www.skepticalscience.com/sea-level-rise-predictions.htm
https://www.theguardian.com/environment/climate-consensus-97-per-cent/2013/dec/04/experts-ipcc-underestimated-sea-level-rise
http://www.news.com.au/world/sea-level-predictions-rise-higher/news-story/776e11c2b14abe5426c29d09b4b9c492
https://www.ipcc.ch/pdf/unfccc/cop19/3_gregory13sbsta.pdf
Additionally, most models do not account for much accelerating melting of ice caps, so they are quite conservative (such as IPCC AR5)
http://www.nature.com/nature/journal/v531/n7596/full/nature17145.html?foxtrotcallback=true
from https://tidesandcurrents.noaa.gov/publications/techrpt83_Global_and_Regional_SLR_Scenarios_for_the_US_final.pdf
However, AR5 recognized the challenges of modeling additions due to the collapse of marine-based sectors of the Antarctic ice sheet. More recent studies of GMSL rise have reported probability ranges that have focused on resolving ranges spanning lower probabilities and/or providing complete conditional probability distributions. An assessment of recent probabilistic studies finds GMSL rise by 2100 projected for the 90% probability (5th95th%) range to fall between 0.250.80 m, 0.350.95 m and 0.51.3 m, respectively, for RCP2.6, 4.5 and 8.5 (Miller et al., 2013; Kopp et al., 2014, 2016a; Slangen et al., 2014; Mengel et al., 2016).
Table 6 on p.23 shows that 12mm per year by 2060 is a very intermediate level prediction.
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zBrown
Ice climber
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Sep 12, 2017 - 06:07pm PT
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The magic is back: Disney reopens in Orlando post-Irma
I ttook a random sample of one and got this result
As I was going to St. Ives,
I met a man with seven wives,
Each wife had seven sacks,
Each sack had seven cats,
Each cat had seven kits:
Kits, cats, sacks, and wives,
How many were there going to St. Ives?
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eeyonkee
Trad climber
Golden, CO
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Sep 12, 2017 - 06:36pm PT
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I just want to, again, express my gratitude to Malemute for providing all of those great links. Although I've probably read only some relatively small percentage of them, they have been a welcome, additional source of data for my world view.
I never really feel like I know something until I can independently write a cogent paragraph or two summarizing my stance while not looking at any source material. Goes something like this.
Starting off with a closed system like climate on the earth:
1. LeChatlier's Rule applies; you perturb the system (e.g., add heat), you should expect the system to try to get itself back to equilibrium (9th grade science)
2. The time to equilibrium matters. The hottest part of the day does not coincide with the maximum incident sun energy (more or less noon). It's always significantly later because of the fact that it takes time to heat things up. Take home? Any fix will require time -- probably decades or more to actually be significant to the system (because it also takes time to cool things off)
3. You have to consider all of the sub-systems that are dependent on climate. Sea-level rise is the most obvious, but there are potentially so many others. A small list off the top of my head based on my reading and general understanding...
a. Larger areas of the US infested with Lyme disease or any other disease vector that gets worse with higher temperatures (most of them)
b. More frequent and/or extreme weather events
c. The exhumation of disease vectors that have not been present on the earth in thousands or tens of thousands of years because of melting glaciers
d. Changes in the major ocean currents
e. Disruption of the primary productive areas of agriculture
f. Collapse of marine subsystems -- coral reefs, for instance because of the acidification of sea water which ultimately happens when you add CO2 to the atmosphere (because of LeChatlier's Rule)
Must be 27 more. I'm thinking that climate change deniers do not really understand LeChatlier's Rule (hopefully I spelled his name right since, you know, I wasn't looking).
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skcreidc
Social climber
SD, CA
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Sep 14, 2017 - 08:56am PT
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f. Collapse of marine subsystems -- coral reefs, for instance because of the acidification of sea water which ultimately happens when you add CO2 to the atmosphere (because of LeChatlier's Rule)
FINALLY, I see someone bringing up collapse of marine subsystems (although I admit I am a part timer here and may have missed a large number of posts). More than half our oxygen is produced in the ocean. As far as we can tell from the rock record, the ocean is the original source of our atmospheric oxygen in the first place. Check out what happened 2.1 billion years ago. Who says life cannot have a major impact on the planet.
But I digress...the ocean is essentially an open carbonate system to one degree or another. It has already been documented that some aragonite shelled organisms (including oxygen producers) in the water column are showing signs of dissolution of their shells depending upon location. The dissolution is related to local lowering of the pH by CO2 equilibrium. The coral reef destruction appears to be mostly related to "bleaching" events caused by higher water temperatures (although cold water bleaching is also known). So it is a related event, but not caused by the same mechanism.
Another comment is that I would say considering the Earths climate a closed system is an assumption, although it may be good enough for our current evaluation.
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Ed Hartouni
Trad climber
Livermore, CA
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Sep 14, 2017 - 07:22pm PT
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Another comment is that I would say considering the Earths climate a closed system is an assumption, although it may be good enough for our current evaluation.
I'm not sure that that is an assumption. The vast majority of energy available to life on planet Earth is from the Sun. It is also what drives most of the atmospheric and oceanic systems.
That makes the Earth's climate NOT a closed system.
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skcreidc
Social climber
SD, CA
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Sep 15, 2017 - 10:13am PT
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Hi Ed. I tend to suck at communication, so this is probably my fault. I totally agree that Earths climate is an open, not closed system. My assumption comment was really in response to Greg's last comment
Starting off with a closed system like climate on the earth:
where after that he went into a list of things related to climate change. To my mind the phrase "starting off with" = "assuming", but I do come at this form an old school perspective. It also is another way of saying "ignoring these factors, we can say bla bla bla" if you get my meaning. For instance, in a basic evaluation of the ocean as an open or closed carbonate system I think you can ignore the sun's effects on Earth and still get good information of potential impacts to the oceans chemistry using that system of equations. The only difference between the two systems would include the partial pressure of CO2 gas (open system with 6 equations vs 5 for closed).
KH = {H2CO3*} / PCO2 = 10-1.47
You are basically assuming a constant source of CO2 and constant temperature in addition to the other five equations.
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Dave
Mountain climber
the ANTI-fresno
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Sep 15, 2017 - 10:39am PT
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First ... assume a spherical chicken ...
The words of my college physics professor.
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Digits
Trad climber
Ca
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Sep 15, 2017 - 02:59pm PT
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Awesomeness!!! We may have alligators thriving once again on Ellesmere Island in the high north of Canada!
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Marlow
Sport climber
OSLO
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Sep 17, 2017 - 12:53pm PT
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Learning from mistakes in climate research
Among papers stating a position on anthropogenic global warming (AGW), 97 % endorse AGW. What is happening with the 2 % of papers that reject AGW? We examine a selection of papers rejecting AGW. An analytical tool has been developed to replicate and test the results and methods used in these studies; our replication reveals a number of methodological flaws, and a pattern of common mistakes emerges that is not visible when looking at single isolated cases. Thus, real-life scientific disputes in some cases can be resolved, and we can learn from mistakes. A common denominator seems to be missing contextual information or ignoring information that does not fit the conclusions, be it other relevant work or related geophysical data. In many cases, shortcomings are due to insufficient model evaluation, leading to results that are not universally valid but rather are an artifact of a particular experimental setup. Other typical weaknesses include false dichotomies, inappropriate statistical methods, or basing conclusions on misconceived or incomplete physics. We also argue that science is never settled and that both mainstream and contrarian papers must be subject to sustained scrutiny. The merit of replication is highlighted and we discuss how the quality of the scientific literature may benefit from replication.
https://link.springer.com/article/10.1007/s00704-015-1597-5
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Digits
Trad climber
Ca
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Sep 17, 2017 - 06:19pm PT
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About 2.5 million years ago, the water level was about 100 feet higher than it is today. The Panhandle of Florida was just the Northern half of what it is today and a small land mass about two-thirds of the peninsula width extended down to Lake City. And a few islands extended as far south as Orlando. You can see evidence of this in the northern part of Tallahassee, where the soil is much like southern Georgia red clay.
https://www.google.com/amp/s/amp.tallahassee.com/amp/29418253
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rbord
Boulder climber
atlanta
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Sep 20, 2017 - 02:26pm PT
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I recommend Breitbart as a good learning tool. The story there today is about a mets pitcher who said that the hurricanes are karma for Trump pulling out of the Paris accord.
Big news! Comments and comments and comments and comments. People like us don't believe in climate change! We get all bent out of shape over something a baseball player says.
Fake news at its finest. Real news of climate change pales in comparison, to a human way of forming beliefs. Yea, it's a problem, from my perspective.
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Lennox
climber
just southwest of the center of the universe
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Sep 21, 2017 - 09:59am PT
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Even if humanity were able to decrease carbon emissions by 2100 to levels identified in the IPCC's best case scenario, a new study indicates that earth will still likely undergo another mass extinction event because of our penchant for sh!tting gigatons of waste where we -- and all the other life in the universe that we know of -- eat, drink and breathe.
http://advances.sciencemag.org/content/3/9/e1700906
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rbord
Boulder climber
atlanta
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Sep 21, 2017 - 10:38am PT
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Thanks for fixing it new world order!
I think we're both talking about the same problem, and however it is that best gets us to tune into the problem - great!
Humans form beliefs for reasons other than the data and logic.
IMHO, gathering data about climate change and using logic on that data are the easy part. Getting humans to believe it is the hard part.
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