[Plantagenet]

Cazenave, A, et al, 2014. The rate of sea-level rise. Nature Climate Change, doi:10.1038/nclimate2159

We find that when correcting for interannual variability, the past decade’s slowdown of the global mean sea level disappears, leading to a similar rate of sea-level rise (of 3.3 ± 0.4 mm yr−1) during the first and second decade of the altimetry era.

Yes, thats just my point. The rate of sea level rise is increasing.

Its not monotonic, and there is inter annual variability, but data regressions all show that sea level is rising more rapidly now then it did 20 years ago, and that rate was more than 50 years ago, and that rate was more than 100 years.

The rate of sea level rise today, at 3.3 mm/yr, is more than triple what it was a century ago. Thats a pretty big honking increase in the rate of sea level rise.

Think about it….every three years sea level goes up about a centimeter now.

And I'll bet you a beer that the rate of sea level rise will continue to increase


Melt the Greenland ice sheet and sea level will go up…..who knew?

[AgentR11]

I created this thread for the purpose of discussing where we are right now in terms of the climate changes we have already set in motion, not the Guy McPherson megadoom scenario but the real scenario we project based on paleoclimate records and real science evidence..

recommend: http://www.scotese.com (paleomap project)
and in particular:


When thinking of paleo climate we get hung up by failing to grasp two very separate time scales.. Right now, it is perfectly reasonably to say we're in a 'warm' period and had an ice age just some x-odd thousand years ago. It is also reasonably to say, right now, that we are in the cold phase of the Earth's climate which varies from an ice bearing form (like now) to one with alligator like animals playing around in the middle of Antarctica and the feet of the Brooks Range. That latter is nothing like any hominid has ever experienced. We are, right now, much much colder than the Earth has been through much of its living history, and of course it also follows, that humans are correctly adapted for this cold, ice bearing state of Earth.

On CO2, we are now moving the needle an amount that is significant in that longer term climate state system; but the problem with that longer term climate state issue is that it is long term, even as fast as we are pushing, its still multi-generational in its full impact on humans.

Basically, humans have had a remarkable pass on survivable zones, we live comfortably on the shores of Arctic ocean to the jungles in the tropics, all without powered technology. That will end. But there are many animal species that live, and live well, within much more restricted climate zones; so I see no reason that same should not apply to hominids. There will be zones that are within tolerance, where food and water can be acquired. Its not a tragedy; its normal. What we are now, is what is not normal. The tragedy is in the journey... changing these rainfall and particular temp/rainfall interaction will break modern calorie crop production. Humans can live fine, with or without tomatoes. Humans do not live fine without sufficient calories, and we use a bunch for our size. You can not grow enough calories in controlled environment greenhouses for 7 billion humans. And you can not grow enough calories for 7 billion humans if the grains involved get the wrong temperatures at the wrong times. Maybe Monsanto will save us for a time, maybe they will fail. But is anyone happy to have the survival of modern civilization dependent upon the actions of the same folks that thought a "terminator" gene was a good idea?

[Graeme]

Here we are right now with sea level rising in New England.

84,000 Lives Threatened By Sea Level Rise In New England

As New Jersey residents loft their rebuilt homes onto five foot pilings along the shore and NYC Mayor Bill de Blasio promises to get work started on 500 storm-demolished homes before Hurricane Sandy’s two year anniversary, a new sea level rise analysis has found that $32 billion in property and 84,000 people are at risk of extreme coastal flooding in five New England states.

As part of its Surging Seas initiative, Climate Central is using data from federal agencies like the National Oceanic and Atmospheric Administration, the Environmental Protection Agency and the U.S. Geological Survey, among many others, to map sea level rise by zip code in an interactive tool that also shows the number of people and the value of the property at risk.

The mapping tool was launched in 2012 for New York, New Jersey and Florida. Now, data on Massachusetts, Rhode Island, New Hampshire, Maine and Connecticut is also available. Of the states just added to the map, Connecticut has the highest value of property at risk from coastal flooding — $14.9 billion. For its part, Massachusetts has about 47,888 people who would be endangered by a four-foot flood. The odds of such a flood occurring in Boston in the next 15 years is 67 percent. Most at risk are the 17,662 people who are highly vulnerable to flooding because of their social and economic situations.

While these may be some of the most alarming statistics, none of these New England states can claim that sea level rise is a distant problem in Bangladesh or the Maldives. New Hampshire has more than $1 billion of property with a 40 percent risk of getting uncomfortably soggy in the next 25 years and Maine has 58,379 acres of land at a similar risk. Even in tiny Rhode Island, there is $4.3 billion worth of property built at an elevation with a one-in-three chance of flooding by 2040.

The tool also allows users to look at the critical buildings and infrastructure that would be affected in different flooding scenarios. The number of hospitals, government buildings, schools, libraries roads and airports that are likely to be impacted in the coming years can be seen at a very local or statewide level with just a few clicks.

“In the lifetime of a new mortgage, coastal residents will see more flooding due to sea-level rise,” said Dr. Benjamin Strauss, director of the Program on Sea Level Rise at Climate Central in a press release.

All U.S. coastal states, including Hawaii and Alaska, will be added to the map by the end of the year.
Related research released this week by scientists at Portland State University found that Manhattan’s seawall is now 20 times more likely to be breached than 170 years ago. Water levels around New York City have already gone up by 1.5 feet since the mid-1800s, The continued rise in sea level and storm tide now means that there is now a one in every four to five years chance of flooding in Manhattan. In the 1800s that chance was once in every 100 to 400 years.

The 1.5 foot of existing sea level rise contributed to the devastating 14-foot storm tide that smashed into Battery Park, at the tip of Manhattan, during Hurricane Sandy.

thinkprogress

[rockdoc123]

Yes, thats just my point. The rate of sea level rise is increasing.

not sure what article you were reading but I bolded this sentence for a reason

Present-day sea-level rise is a major indicator of climate change1. Since the early 1990s, sea level rose at a mean rate of ~3.1 mm yr−1. However, over the last decade a slowdown of this rate, of about 30%, has been recorded. It coincides with a plateau in Earth’s mean surface temperature evolution, known as the recent pause in warming. H

They aren't agreeing with your statement that sea level rise has been accelerating , just the opposite.

So they say that "over the last decade a slowdown of this rate of about 30% has been recorded" and somehow you read that they agree with your statement that sea level rise is accelerating.

Can't help you with the cognitive issues

[rockdoc123]

Wow, you seem to have lots of confusion yourself, there, as you equate 'fact,' 'measurement,' and 'observation.'

Perhaps an investment in a dictionary may help you out, or a few seconds spent checking common definitions.

Not really worth speaking further with one so utterly confused (or willfully trying to confuse others).

amazing how you just love to show your ignorance time and again.

definition of Fact: Knowledge or information based on real occurrences

A measurement is factual.....an observation without interpretation is factual. An interpretation is not factual.

Quite simple.....like you.

[dohboi]

A wrote: "You can not grow enough calories in controlled environment greenhouses for 7 billion humans." Good point. One lost on many techno-optimists.

(OMG, now rd is just pulling definitions out of his posterior as he does with everything else. How embarrassing.)

[Plantagenet]

Yes, thats just my point. The rate of sea level rise is increasing.

not sure what article you were reading but I bolded this sentence for a reason

Present-day sea-level rise is a major indicator of climate change1. Since the early 1990s, sea level rose at a mean rate of ~3.1 mm yr−1. However, over the last decade a slowdown of this rate, of about 30%, has been recorded. It coincides with a plateau in Earth’s mean surface temperature evolution, known as the recent pause in warming. H

I guess in response I'd better bold another statement from the same paper:

We find that when correcting for interannual variability, the past decade’s slowdown of the global mean sea level disappears, leading to a similar rate of sea-level rise (of 3.3 ± 0.4 mm yr−1) during the first and second decade of the altimetry era.

So the slowdown you are touting disappears after correcting for interannual variability.

I'm not going to sink as low as you did and echo your claim that you missed this because your 'cognitive" skills are lacking. IMHO you are sharp and clever and your cognitive skills are fine. But i do think you are selectively taking words and phrases out of context that fit your bias against global warming, without objectively looking at all the data and all the conclusions of the paper you are citing.

The data itself is clear---the rate of sea level rise has been steadily increasing from the late 19th century to today. This rate has gone from ca. 0.9 mm/yr to the current 3.3 mm/yr, i.e. the rate of sea level rise has more than tripled.

Why deny it? The rate of sea level rise has tripled since the first instrumental measurements were made in the late 19th century---thats not some piddly little increase in the rate of sea level rise that can be ignored or fudged away---the rate has TRIPLED----thats a very significant increase in the rate of sea level rise.

[Graeme]

Yes, rd forgot about storm surges:

Water levels around New York City have already gone up by 1.5 feet since the mid-1800s, The continued rise in sea level and storm tide now means that there is now a one in every four to five years chance of flooding in Manhattan. In the 1800s that chance was once in every 100 to 400 years.

The 1.5 foot of existing sea level rise contributed to the devastating 14-foot storm tide that smashed into Battery Park, at the tip of Manhattan, during Hurricane Sandy.

[rockdoc123]

so the slowdown you are touting disappears after correcting for interannual variability.

I'm not going to sink as low as you did and echo your claim that you missed this because your 'cognitive" skills are lacking. IMHO you are sharp and clever and your cognitive skills are fine. But i do think you are selectively taking words and phrases out of context that fit your bias against global warming, without objectively looking at all the data and all the conclusions of the paper you are citing.

You and dohboi are suffering from the same problem....mixing up real data with modeled interpretations.

Once again....the data review (no interpretation here as to what caused it just what it says) indicates that not only is there no acceleration but there is a deceleration, precisely why I bolded what I did.

Based on a modeling study they Interpret that one possibly solution (again this is not a unique solution) is that it has to do with ENSO. Alternatively it might have nothing to do with ENSO....there may be another reason or a score of reasons that combine together...they did not look at all the possible outcomes. Regardless of their interpretation of what caused it they do not argue that sea level rise as measured has not only not accelerated but has actually decelerated.

[rockdoc123]

Yes, rd forgot about storm surges:

No but you forgot to check and see how much Manhattan has been subsiding into the ocean. It is relative sea level rise not actual sea level rise in this case.

satellite data show no sea level rise for the area whereas tide gauge data show considerable sea level rise.....this means it is subsidence not rising seas.

apparently most of the building in the past couple of centuries has been on fill which of course subides under weight.

http://xmmlbchat.blogspot.ca/2012/05/sea-level-not-rising-in-manhattan.html

[Plantagenet]

....the data review (no interpretation here as to what caused it just what it says) indicates that not only is there no acceleration but there is a deceleration, precisely why I bolded what I did.

Over the short term there are large annual variations in the rate of sea level rise. These reflect transient influxes of water into the ocean due to seasonal melting of glaciers, among other effects. When you remove the annual variations, which can be done by simple statistical treatments such as using running means or linear regression or curve fitting, the "deceleration" disappears, and the rate of sea level rise is found to be 3.3 mm/yr---the highest rate yet measured.

Pray tell where is the "deceleration" in the rate of sea level rise if the current rate of sea level rise is ca. 3.3 mm/yr, i.e. is the highest ever measured?


Notice the slope of the regression line fitted to sea level. The slope is a function of the rate of sea level change. The fact that the slope of this regression line is as steep or steeper than all regression lines plotted for all time series of sea level elevation at any time in the 20th century demonstrates there has been no "deceleration" in the rate of sea level rise.

Wheeee! Math is fun!!!

[dohboi]

all of the land-ocean records used in the IPCC AR5 report have been overstating the slowdown in warming over the past 16 years

(Emphasis in the original.)

https://www.skepticalscience.com/how_gl ... ecord.html

[Tanada]

I created this thread for the purpose of discussing where we are right now in terms of the climate changes we have already set in motion, not the Guy McPherson megadoom scenario but the real scenario we project based on paleoclimate records and real science evidence..

recommend: http://www.scotese.com (paleomap project)
and in particular:


When thinking of paleo climate we get hung up by failing to grasp two very separate time scales.. Right now, it is perfectly reasonably to say we're in a 'warm' period and had an ice age just some x-odd thousand years ago. It is also reasonably to say, right now, that we are in the cold phase of the Earth's climate which varies from an ice bearing form (like now) to one with alligator like animals playing around in the middle of Antarctica and the feet of the Brooks Range. That latter is nothing like any hominid has ever experienced. We are, right now, much much colder than the Earth has been through much of its living history, and of course it also follows, that humans are correctly adapted for this cold, ice bearing state of Earth.

On CO2, we are now moving the needle an amount that is significant in that longer term climate state system; but the problem with that longer term climate state issue is that it is long term, even as fast as we are pushing, its still multi-generational in its full impact on humans.

Basically, humans have had a remarkable pass on survivable zones, we live comfortably on the shores of Arctic ocean to the jungles in the tropics, all without powered technology. That will end. But there are many animal species that live, and live well, within much more restricted climate zones; so I see no reason that same should not apply to hominids. There will be zones that are within tolerance, where food and water can be acquired. Its not a tragedy; its normal. What we are now, is what is not normal. The tragedy is in the journey... changing these rainfall and particular temp/rainfall interaction will break modern calorie crop production. Humans can live fine, with or without tomatoes. Humans do not live fine without sufficient calories, and we use a bunch for our size. You can not grow enough calories in controlled environment greenhouses for 7 billion humans. And you can not grow enough calories for 7 billion humans if the grains involved get the wrong temperatures at the wrong times. Maybe Monsanto will save us for a time, maybe they will fail. But is anyone happy to have the survival of modern civilization dependent upon the actions of the same folks that thought a "terminator" gene was a good idea?

This particular graph is one of the reasons I consider the Venus scale runaway greenhouse Earth scenario to be pure fantasy. In all of the known geological record the temperature of the Earth has stayed between two boundaries, +25 C and +10 C as global average temperature. The idea that we will suddenly deviate from that pattern by such a large amount as to vaporize the oceans is pure sophistry IMO. Perhaps it is useful in some circles to exaggerate to make the point that climate change is dangerous, but to me it serves to hinder change because anyone who spends even a few hours looking at past climate will find this graph or one very much like it showing that the Earth has a remarkably consistent climate history. Once you know that you stop taking wild claims seriously and as a side effect you stop listening to the more credible claims in the process.

[Lore]

Once you know that you stop taking wild claims seriously and as a side effect you stop listening to the more credible claims in the process.

Who's the we? I don't buy the fact that people can't use average intelligence with a little effort to cut through the crap and uncap the real facts. The world's leading climate scientists seem to have a pretty good grasp of what's happening and is about to. I certainly trust that authority more than blog science posted by amateurs.

There is also such a thing as going in the opposite direction of soft peddling some of the more dire outcomes in favor of a positive message, magical thinking and irrational salvation and hope. Which only ends up giving those unable to handle the truth an excuse to ignore and do nothing while living under a false sense of security. This is exactly what the BAU crowd hopes to sucker everyone into.

[rockdoc123]

Pray tell where is the "deceleration" in the rate of sea level rise if the current rate of sea level rise is ca. 3.3 mm/yr, i.e. is the highest ever measured?

Jezus…..read the frigging paper. Send a Discussion to the Journal if you disagree with their interpretation.

Notice the slope of the regression line fitted to sea level. The slope is a function of the rate of sea level change. The fact that the slope of this regression line is as steep or steeper than all regression lines plotted for all time series of sea level elevation at any time in the 20th century demonstrates there has been no "deceleration" in the rate of sea level rise.

The deceleration they speak to is based on decadal analysis. Again read the frigging paper.

[Plantagenet]

Pray tell where is the "deceleration" in the rate of sea level rise if the current rate of sea level rise is ca. 3.3 mm/yr, i.e. is the highest ever measured?

Jezus…..read the frigging paper..... read the frigging paper.

I've read the frigging paper (by the way---can scientific papers "frig"?). I've even quoted it to you. The paper says there is no deceleration. The paper says the rate of sea level rise is now 3.3 mm/yr, the highest ever recorded.

Thats why I'm politely asking you to please explicate your claim that there is a "deceleration" in the rate of sea-level rise. What was the maximum rate of sea-level rise? What is the rate of sea rise now that it has "decelerated"? Is the data showing the current rate of sea level rise is now more than three times higher now then it was in the early 20th century somehow flawed?


King Canute orders the sea not to rise

[dohboi]

T wrote: "In all of the known geological record the temperature of the Earth has stayed between two boundaries, +25 C and +10 C as global average temperature"

AFAIK, even those who say a Venus-runaway may be possible don't say it's probable. IIRC it is mostly Hansen who has brought this up as a remote possibility. He was one of the first to study Venus as a planetary system, so I wouldn't rule out his judgment based on one graph. The past is, after all, no guarantee of the future. For one thing, the sun is now hotter than at any other time in that graph. Also, at no other time in that graph were jets regularly emitting CO2 and water vapor high in the atmosphere.

In any case, if it could possibly happen, everyone agrees that it would not be for a very long time in the future. And of course if you go far enough in the future, the earth will indeed become hotter than Venus, as the sun continues to warm. The most pressing concern is what is likely to happen in the next decades and next few centuries. In that time period, we cannot rule out temperatures that will make most of the earth un-inhabitably hot and humid, with much higher sea levels.

As Richard Allen has pointed out with regard to the possibility of relatively sudden sea level rise, even if a very catastrophic outcome has a relatively low probability, we ought to be doing all we can to reduce that probability and to prepare ourselves for if it comes. After all, Most of us put on our seat belts every time we drive, even if we think there is something less than a .01% chance that we will get into a major accident on that particular trip.

[rockdoc123]

The paper says there is no deceleration.

Jesus wept……this from the abstract:

However, over the last decade a slowdown of this rate, of about 30%, has been recorded.

in what language does "slowdown" not equate with "deceleration" ??

[Newfie]

Tanda,
First, I really hope you are right, that we do not face a Venus like future.

I would feel more comfortable if CO2 levels were posted on that graph also so I could get a sense of what temp equated to which CO2 level.

But I have two points I ponder.

My understanding is that the Venus hypothotsis rests on the assumption that moving to a warm world state would release vast amounts of methane in unprecedented quantities, moving the CO2 levels above what has been experienced previously. To make an anology, it is as if Earth has built up cumulative quantities of a toxin, and we are about to release it all at once.

Secondly, I think it's pretty clear that such an event is, in human terms, pretty far off. Several generations at least. On a shorter scale however we have the greater possibility of some significant die off due, in part to climate change. I don't fear sea level rise, an annoyance at best. I do fear that the cumulative stresses of sea level rise, drought, floods, and greater environmental variability on food supplies will conspire with peak oil, and general resource depletion to destabilize our global financial and govermental system so that we experience some degree of societal/cultural contraction/collapse.

There are several types of extinction. We all face personal extinction for we all die. Species extinction occurs when our genetic line dies. But succeess in keeping alive some small number of breeding pairs seems cold comfort. Not that I'm happy with our curren overshoot state, but I don't relish the curative either.

[dissident]

The Venus theme is nonsense that will only act to validate the denier claims about alarmists. Even if all the carbon reservoirs (not bound up in rock) were somehow to be released, the resulting CO2 + CH4 would not even reach 10% of the atmospheric mass. And all of this CO2 + CH4 and induced H2O increase would raise temperatures of the globe by between 10 and 15 Celsius. This is nowhere near enough to boil off the oceans. Venus has no relevance because its atmospheric composition was not the result of a runaway greenhouse effect on some Earth-like climate. It simply failed to precipitate the water into oceans and sequester the CO2 into carbonate rocks. So that today, the Venus atmosphere is 95% CO2 just like it was after it formed and just like on Earth at the same stage of formation.

Some methane carbon budgets:

clathrates - under 10 teraton
permafrost - 1 teraton
integrated human emissions from hydrocarbon reservoirs - 0.01 teraton

integrated human emissions of CO2 carbon - under 2 teraton.
reservoir of ocean CO2 than can be outgassed under warming - <pick a number under 100 teraton>

Neither the permafrost nor the clathrates come out as pure CH4 but let us say the all come out as CH4 and all at once (a state that is not accessible unless the Earth get's walloped my a massive meteor impact that would do humanity in all by itself). So we have 12 teraton of CH4 carbon or 16 teraton of CH4. Since CH4 is 75 times more potent compared to CO2, this is like 1200 teraton of CO2. (All of the CO2 sources can be neglected.) The current CO2 burden in the atmosphere is 3 teraton so we have a 400 fold increase, the temperature increase should follow:

dT = T-T_now = C * log_e(400) = C * 6

If C = 3 degrees Celsius, then dT = 18 Celsius. If C = 6 degrees Celsius, then dT = 36 Celsius.

Note that the whole premise of this calculation is utter rubbish. Neither the clathrates nor the permafrost could be released all at once and as CH4. They can be released slowly over centuries (especially the clathrates) and have a very large part be converted to CO2 via bacteria. In both the land and ocean ecosystems a large collection of bacterial species exist by consuming CH4. So even if the climate sensitivity was really, really high the global temperature change would not be even anywhere near 36 Celsius.

The Earth managed to condense oceans in an atmosphere composed of 95% CO2. We can't even make it so bad as to re-create those conditions and so, accounting for the increased solar radiance over the age of the Earth, we are not going to drive the system into any runaway greenhouse regime.

Anyone peddling the fictional "Venus runaway greenhouse" climate crock needs to put the crack pipe down. That includes Dr. Hansen.