Eric Worrall writes of a new paper trying to blame sea level rise on The Industrial Revolution, which started about 150 years ago:
The Australian National University has published a startling claim that sea level change has been more or less steady for the last 6000 years – until 150 years ago, when the sea started rising more rapidly.
According to the Abstract:
“Several areas of earth science require knowledge of the fluctuations in sea level and ice volume through glacial cycles. These include understanding past ice sheets and providing boundary conditions for paleoclimate models, calibrating marine-sediment isotopic records, and providing the background signal for evaluating anthropogenic contributions to sea level. From ∼1,000 observations of sea level, allowing for isostatic and tectonic contributions, we have quantified the rise and fall in global ocean and ice volumes for the past 35,000 years. Of particular note is that during the ∼6,000 y up to the start of the recent rise ∼100−150 y ago, there is no evidence for global oscillations in sea level on time scales exceeding ∼200 y duration or 15−20 cm amplitude.”
The abstract is at: http://www.pnas.org/content/early/2014/10/08/1411762111
The abstract notes that on longer timescales, SLR up to at least 40mm / year has been observed – so in this context “a few” mm per year does not seem particularly alarming, and is well within the range of natural variation. The fluctuation claim – the claim that sea level change in the last 150 years is faster than any change over the last 6000 years – is very much dependent on accurate dating of each of the proxy series. As we saw with the Hockey Stick controversies, any uncertainty about dating proxies tends to impose a strong hidden averaging effect on the data series, smoothing away peaks and troughs.
In any case, in many locations the current rate of change in sea level is swamped by local geological changes – one of the reasons changes in sea level are so difficult to calculate, is the land in many locations rises or falls faster than the alleged change in sea level.
Anthony adds:
But, other science suggests even higher sea levels during interglacials.
A paper published April 17th 2014 in Nature reconstructs sea levels over the past 5.3 million years and shows that sea levels were higher than the present during almost every interglacial period over the past 5.3 million years. Sea levels at present during the current interglacial are indicated as the added red horizontal line at zero meters on Fig. 2 below, and excursions above this line indicate sea levels during past interglacials as much as 50+ meters [164+ feet] higher than present sea levels. Thus, there is no evidence that sea level rise during the present interglacial is unprecedented, unnatural, unusual or any different from that which occurred in prior interglacials, or any evidence of influence by man on sea levels.
E. J. Rohling, G. L. Foster, K. M. Grant, G. Marino, A. P. Roberts, M. E. Tamisiea, F. Williams. Sea-level and deep-sea-temperature variability over the past 5.3 million years. Nature, 2014; DOI: 10.1038/nature13230
Fig. 2 with added red horizontal lines show present sea levels. Horizontal axis is thousands of years before the present.
The last interglacial ~100,000 years ago [Eemian] had sea levels between 16-31 feet higher than the present, although it appears as a tiny blip above the red line in the above graph with a much more compressed scale, but is better appreciated by this graph from another recent paper:
Sea levels during the last interglacial ~120,000 years ago were up to 5 meters higher than the present in this location and up to 9.5 meters higher at other locations (h/t to The Hockey Shtick)
So, if we had sea levels of 16-31 feet higher than the present 100,000 years ago, well before the dawn of the industrial revolution, what caused that? Inquiring minds want to know.
While climateers look for the bad in everything about our modern standard of living related to climate, this is worth noting:
In the words of Nobel Prize winning Robert E. Lucas, Jr.,
For the first time in history, the living standards of the masses of ordinary people have begun to undergo sustained growth. … Nothing remotely like this economic behavior has happened before.
Source: Landes, David S. (1969). The Unbound Prometheus: Technological Change and Industrial Development in Western Europe from 1750 to the Present. Cambridge, New York: Press Syndicate of the University of Cambridge. ISBN 0-521-09418-6.
UPDATE: Chip Knappenberger sends this graph along:
Note the tiny blip at the right, our present sea level rise.
Anthony, I think the ‘No change in sea level until modern times” is a misstatement. It should be more like “No change in rate of sea level rise until modern times’.
I think the distinction is important, other wise your adversaries will accuse you of exaggerating (or worse, like they usually do)
a progressive decrease in the rate of rise from 8.2 ka to ∼2.5 ka BP, after which ocean volumes remained nearly constant until the renewed sea-level rise at 100–150 y ago, with no evidence of oscillations exceeding ∼15–20 cm in time intervals ≥200 y from 6 to 0.15 ka BP.
They could work on their clarity a little but here in the abstract is says that sea level was nearly constant for about 2,350 years and then it began to rise. They claim that since the Holocene Climate Optimum no change in sea level persisted for more than 200 years and didn’t vary by more than 15-20 cm during that time.
A normal scientist, after concluding this, would say whoa! Why don’t our conclusions on sea level correlate with inferred changes in global temperature in this time interval? Why doesn’t this match what others have concluded about the growth and retreat of glaciers over this time interval? Why do our conclusions not match these:
Nunn, P.D. (2000). “Environmental catastrophe in the Pacific Islands around AD 1300”. Geoarchaeology 15 (7): 715–40.
G. Schernewski und T. Dolch (Hrsg.): Geographie der Meere und Küsten
Coastline Reports 1 (2004),
Kemp et al., Climate related sea-level variations over the past two millennia, PNAS 2011.
And of course the question of why did the modern sea level begin to rise before CO2 emissions from man could have caused it and why has the rate remained constant even decades after man’s supposed influence kicks in?
Seawater thermal expansion is more pronounced at higher pressure. This leads to sea level rise as energy taken up by the ocean migrates down into deep water. Because the energy transfer can take over 1000 years we see sea level changes which reflect (in part) this delayed effect. For example, the cold pulse from the Little Ice Age is migrating down at this time behind an earlier pulse from the medieval warm period. These older pulses are “printed over” by the temperature increase since the little ice age ended. The net result is sea level change which may not match the surface temperature at a single point in time.
That’s interesting. The claim that I have trouble with is that “∼2.5 ka BP, after which ocean volumes remained nearly constant until the renewed sea-level rise at 100–150 y ago.” Even with this lag effect there should be some sea level change occurring somewhere, if not eustatic. These results sound like they were preordained from the hockey stick but I haven’t seen their reconstruction so not sure.
Nearly everywhere you look you can find evidence of changing sea levels. It is a highly localized phenomenon, from the Palisade coastline of Southern California to the submerged megaliths of the English Channel and paleolithic dwelling sites under the North Sea. It all depends on both the place and time one is examining.
Coral atolls would not exist if the local sea level had not fallen below the level it held when the atoll was built.
Reefs would not grow if the local sea level had not risen.
The sea goes up; the sea goes down.
“The sea goes up; the sea goes down.”
As do the temperatures. They go up and they go down. Who is to say what level is the “best” in either case.
Sometimes they add more rain to earth. It may come from Mars, Venus, Jupiter or a meteor while we are sleeping. This is the only way that sea levels could rise. if we assume that land rises and falls, Ice melts and freezes and these can impact sea levels at various parts of the world.
But I believe the theory of water from the heavens. And that is caused by the Bible Belt folks, those dastardly Republicans. Poor democrats have to sit and worry about the sea-level rise, when they are not driving their limo or flying around on jets, usually on gov’t money. we republicans have to pay the bill.
The situation with the reefs does not seem to bother the warmists atoll.
About 150 years ago, we were coming out of the Little Ice Age. It makes sense that the rate of sea level rise should have started to increase within that time frame.
Exactly.
Cherry picking at its very best indeed.
This should be provable by observing the pattern of rate of SL change prior to going into the LIA.
http://c3headlines.typepad.com/.a/6a010536b58035970c015433ac485d970c-pi
After reviewing the paper, the authors admit to using a low resolution modeling.
As far as AW’s comment, the author’s have this text in their Results section, “Where available, evidence for
the Last Interglacial (marine isotope stage 5.5) shoreline, formed when, globally, sea levels were ∼4–8 m above present (43, 44), has been used to assess the long-term stability of the region or to correct for tectonic displacement.”
They finish the paper with a dozen “features” of their model and their findings. #12 is of most note. Here it is:
These features are:
i) A period of a relatively slow fall in sea level from 35 to
31 ka BP followed by a rapid fall during 31–29 ka. This
is based on data from Barbados, Bonaparte Gulf, Huon
Peninsula (Papua New Guinea), and a few isolated observations
from the Malay Peninsula and the Bengal Fan. It
points to a period of rapid ice growth of ∼25 m esl within
∼1,000 y to mark the onset of the peak glaciation, consistent
with the transition out of the Scandinavian Ålesund
Interstadial into the glacial maximum (75), although this
ice sheet alone is inadequate to contribute 25 m to esl.
Chronologically, the timing of the rapid fall corresponds
to the nominal age for the Heinrich H3 event (76, 77).
ii) Approximately constant or slowly increasing ice volumes
from ∼29–21 ka BP. The data for this interval are sparse
but are from geographically well-distributed sites (Barbados,
Bonaparte, Bengal Fan, East China Sea, and Maldives). The
slow increase in ice volume is consistent with eastward and
southward expansion of the Scandinavian ice sheet during
the LGM (78) as well as with the southward advance of the
Laurentide ice sheet (79). The esl reaches its lowest value of
∼134 m at the end of this interval, corresponding to ∼52 ×
106 km3 more grounded ice—including on shelves—at the
LGM than today. This is greater than the frequently cited
−125 m (e.g., 24, 80) that is usually based on observations
uncorrected for isostatic effects. Heinrich event H2 at
∼19.5–22 14C ka (∼25 ka BP) (77, 81, 82) is not associated
with a recognizable sea-level signal.
iii) Onset of deglaciation at ∼21–20 ka BP with a short-lived
global sea-level rise of ∼10–15 m before 18 ka. The evidence
comes from the Bonaparte Gulf (37, 38), has been
identified elsewhere (83, 84), and is supported by isolated
observations from five other locations (Bengal Bay, Cape St
Francis (South Africa), offshore Sydney, Barbados, Maldives)
which, although less precise than the principal data
set, spread the rise over a longer time interval than originally
suggested. Chronologically, this rise occurs substantially
later than the H2 event.
iv) A short period of near-constant sea level from ∼18–16.5 ka
BP. Support for this comes from observations from
Barbados, the Sunda Shelf, Bonaparte Gulf, Mayotte,
and Cape St Francis.
v) A major phase of deglaciation from ∼16.5–7 ka BP. The
total esl change in this interval is ∼120 m, at an average rate
of ∼12 m·ka−1, corresponding to a reduction of grounded
ice volume of ∼45 × 106 km3). Within this interval, significant
departures from the average occur.
vi) A rise of ∼25 m from ∼16.5–15 ka BP at the long-term
average rate of ∼12 m·ka−1. The data are from Sunda,
Tahiti, the East China Sea, Mayotte, and Australia. Chronologically,
the onset of this rise occurs at the time of the
H1 event dated at 16.8 ka (85) or 16 ka (86). This period of
rising sea level is followed by a short period (∼500–600 y) of
near-constant sea level.
vii) A high rate of sea-level rise starting at ∼14.5 ka BP of ∼500 y
duration. The onset occurs at the start of the Bølling−
Allerød warm period. Its duration could be <500 y because
of uncertainties in chronology, and the globally averaged rise
in sea level of ∼20 m occurs at a rate of ∼40 mm·y−1 or
greater. This pulse, MWP-1A, has been identified separately
in the records of Barbados (24), Sunda (33), and Tahiti (28,
87). Spatial variation in its amplitude can be expected because
of the planet’s elastic and gravitational response to
rapid unloading of ice in either or both of the two hemispheres
(88) with, based on the ice−earth models used here,
model-predicted values ranging from ∼14 m for Barbados to
∼20 m for Tahiti (SI Appendix, Fig. S4). This compares with
observational values of ∼15–20 m (24, 28) for Barbados and
12–22 m for Tahiti (28). Observational uncertainties remain
large, including differences in the timing of this event as
recorded at the different localities, and it is not possible from
this evidence to ascertain the relative importance of the contribution
of the two hemispheres to MWP-1A.
viii) A period of sea-level rise from ∼14 to ∼12.5 ka BP of
∼20 m in 1,500 y. The rate of rise is near the long-term
average. Data are relatively dense in this interval and come
from well-distributed sites (Barbados, Tahiti, Sunda, Huon
Peninsula, Australia and New Zealand, Indian Ocean, and
the Yellow and East China seas).
ix) A period of a much reduced rate of rise from ∼12.5–11.5 ka
BP. This short duration pause in the sea-level rise has been
tenuously noted before in both composite (89) and individual
(27) records. The chronology corresponds to the timing of the
Younger Dryas stadial of the Northern Hemisphere when
retreat of the Northern Hemisphere ice sheets ceased momentarily.
x) A period from ∼11.4–8.2 ka BP of near-uniform global rise.
The average rate of rise during this 3.3 ka interval was
∼15 m·ka−1 with little convincing evidence of variations
in this rate. A rapid rise, MWP-1B, has been reported at
∼11.3 ka but remains elusive (27) and is not seen in the
composite record other than as a slightly higher rate of
increase to ∼16.5 mm·y−1 for a 500-y period immediately
after the Younger Dryas period.
xi) A reduced rate of sea-level rise for 8.2–6.7 ka BP. This is
consistent with the final phase of North American deglaciation
at ∼7 ka BP. A marked cooling event has been recorded
at 8.2 ka BP in Greenland and North Atlantic cores (90), but
there is no suggestion in the sea-level record of a corresponding
fall or slowdown in global sea-level rise. The
detailed local record from Singapore from 8.5 to 6 ka
BP (40, 41) is consistent with the global rates within this
interval except that a period of near-zero rise from 7.8 to
7.4 ka is not seen globally, possibly lost in the noise of
other observations at around this time, possibly because it
reflects local phenomena (Fig. 4).
xii) A progressive decrease in rate of rise from 6.7 ka to recent
time. This interval comprises nearly 60% of the database
(Fig. 1). The total global rise for the past 6.7 ka was ∼4 m
(∼1.2 × 106 km3 of grounded ice), of which ∼3 m occurred
in the interval 6.7–4.2 ka BP with a further rise of ≤1 m up
to the time of onset of recent sea-level rise ∼100–150 y ago
(91, 92). In this interval of 4.2 ka to ∼0.15 ka, there is no
evidence for oscillations in global-mean sea level of amplitudes
exceeding 15–20 cm on time scales of ∼200 y (about
equal to the accuracy of radiocarbon ages for this period,
taking into consideration reservoir uncertainties; also, bins
of 200 y contain an average of ∼15 observations/bin). This
absence of oscillations in sea level for this period is consistent
with the most complete record of microatoll data from
Kiritimati (23). The record for the past 1,000 y is sparse
compared with that from 1 to 6.7 ka BP, but there is no
evidence in this data set to indicate that regional climate
fluctuations, such as the Medieval warm period followed by
the Little Ice Age, are associated with significant global
sea-level oscillations.
====================
Note: the Kiritimati atoll comparison. I thought the coral atolls are essentially hydrodynamically self-adjusting?
If anyone would like a pdf of this paper, email me with the request to:
joel(dot)obryan(at)gmail(dot)com
Very thorough. Well done.
Nice, thank you.
This to me seems like a preconceived conclusion disguised as science. There are too much data that shows glaciers, throughout most of the world, advanced and retreated during the LIA and MWP respectively (not to mention the other climate oscillations during the Holocene). These climate oscillations show up in the ice cores at both ends of the world and in alpine glaciers. So where is the sea level oscillation that should be associated with them? Oh that’s right, they are desperately attempting to erase these climate oscillations.
Glacial geological evidence for the Medieval Warm Period
JM Grove, R Switsur – Climatic Change, 1994 – Springer
Holocene climate variability
PA Mayewski, EE Rohling, J Curt Stager, W Karlén… – Quaternary …, 2004 – Elsevier
Holocene climate variability in Antarctica based on 11 ice-core isotopic records
V Masson, F Vimeux, J Jouzel, V Morgan… – Quaternary …, 2000 – Elsevier
Oxygen isotope and palaeotemperature records from six Greenland ice-core stations: Camp Century, Dye-3, GRIP, GISP2, Renland and NorthGRIP
SJ Johnsen, D Dahl-Jensen… – Journal of …, 2001 – adsabs.harvard.edu
It is absolutely amazing that people publish such absolute fantasy as sea levels over the lat 5.3 million years when they cant even agree on what sea level is today. We dont know what sea level is today but we can publish graphics of what they were over the last million years. Sea level 120 years ago was perhaps 5 to 9 Meters higher the report states, when Pillow Lava covers Mount Ararat at 5000 Meters above todays Sea level and Pillow Lava Covers Mt Kilamanjaro in Africa at 6000 Meters above sea level today. Pillow Lava also covers much of the Hymalayas although most of it has been eroded over ages. So which means that sea level was as high as Mount everest at one time 8800meters above today ,s sea level. So please explain? DId you say sea levels have not risen: what about fell???
Richard Guy
Errmmm……
Tectonic uplift…Himalayas are still rising because of the collision of north -moving India with Asia.
Rate of uplift is up to 10mm a year [1 metre/century] so you could potentially get 6000m of uplift in 600,000 years.
Rates of uplift in Papua New Guinea have been calculated by the USGS [http://pubs.er.usgs.gov/publication/70020019] at up to 2.1m/1000 years which would give you 6000m of uplift in 3 million years which is a bit more reasonable.
So it is not that Mount Everest was covered by sea but Mount Everest has risen from the sea.
The real [net] rate of uplift depends on the erosion rate as well.
Yes I saw Costner’s ‘Waterworld’. But then I looked it up in Wikipedia and found that if the every piece of ice on Earth melted the seas would only rise about 200 feet. I live in a major American city – not the country or even the suburbs, I live within city borders – at 1,000 feet. Bring it on. This is just about the silliest thing to worry about that I can imagine.
6000 years ago? Why does anyone other than an academic care?
On a more recent note I took a closer look at the tide gauge data
from the U.S. West coast as follows:
There are 24 West coast tide gauge stations that have data going
back to at least 1986 many with much longer records. Twenty-one
of them show negative rates back to at least 1992 some have
negative rates since the beginning. La Jolla and San Diego have
long records and have never shown a long period with a negative rate.
Humboldt seems to be an anomaly with a very high rate of 4.5 mm/yr
since 1985.
Here’s the list from North to South:
Sta# Station Negative Sea Level Rise
1633 Cherry Pt Since 1986
384 Ocean Labs Since 1992
385 Neah Bay Always Since 1935
2127 Port Angeles Since 1976
1325 Port Townsend Since 1991
127 Seattle Since 1992
1354 Toke Pt Since 1979
265 Astoria Always Since 1925
1196 South Beach Since 1982
1269 Charleston II Since 1981
1640 Port Orford Since 1990
378 Crescent City Always Since 1933
1639 Humboldt Never Negative since 1985
2125 Arena Cove Always Since 1972
1394 Pt Reyes Since 1993
10 San Francisco Since 1981
437 Alameda Since 1977
1352 Monterey Since 1980
508 Port San Luis Since 1978
2126 Santa Barbara Since 1977
377 Santa Monica Since 1992
245 Los Angeles Since 1991
256 La Jolla Never Negative since 1925
158 San Diego Never Negative since 1906
Negative sea level rise since such and such date doesn’t mean the
ocean has significantly dropped since then, but rather there hasn’t
been a change. However, the long term stations that have been
negative since the ’20s and ’30s do show a drop.
Maybe this is old news, but I was surprised that 21 of 24 West coast tide
gauges have negative rates of sea level rise for at least the last 20 years
Don’t be. The west coast is tectonically active.
Well, think about the location of the off-shore tectonic plates (and the direction of their relative movement with respect to the “waterline” on the west coast.
A “negative rate of sea level rise” means the coastal lands are “higher” now than they were in times previous. So, either the sea level went down or the coastal lands went up, right?
OK, if some of the Pacific plates under the water offshore are moving east (with respect to the coastline) then those tons of dirt, underwater silt and debris, and rock are getting pushed under the local shallower land, right?
If so, then the newly pushed under dirt and ocean floor and debris is getting shoved ever deeper and deeper, and it will eventually melt, rise, and be seen much, much later as inland volcanoes 100-odd miles back from the Pacific coast. And, indeed, we do see such volcanoes, so its reasonable to assume the ocean floor is getting pushed under the coastal rocks.
If billions of tons of ocean floor are going under land-based rocks, then would you not expect those land-based rocks to go up? And thus, the seawater hitting those newly-raised shoreline rocks will appear to be going down.
But, what about the other areas? Well, again, is the offshore ocean bottom getting shoved under the land-based rocks, or are the two going past each other? If Baja is splitting from Mexico, where are those three parts:(original land, left side of the split, right side of the split, and focus point of the split) going? Headed east, west, northwest, up, or down?
I have also studied those NOAA mean sea level trends for the west coast. With only three or four exceptions they show a flat trend from about the mid-80’s. There are couple that record a slight rise which is due to local subsidence and one (Neah Bay) that shows a fall in sea level and this is due to local uplift.
The flat trend is confirmed by NOAA mean sea level trends for the Gulf of Mexico guages which show a flat trend for the last 15 years or so except for a few, such as Grand Isle which is subsiding and so registers a rising SL.
East coast guages likewise register a flat trend as far north as Chesapeake Bay and this region is subsiding due to ground water withdrawal.
Conclusion: Pay no attention to the talk about sea level rise; it is simply more of the same disinformation and misinformation propagated by alarmists.
but there is no
evidence in this data set to indicate that regional climate
fluctuations, such as the Medieval warm period followed by
the Little Ice Age, are associated with significant global
sea-level oscillations.
===============
so sea levels are not a proxy for warming/cooling?
Bingo.
Well, no. But you get finding by suggesting there is. Research funding is like a giant ATM in the sky where the pin number is AGW.
New paper claims after 6,000 year ‘pause’, sea levels began rising 150 years ago
http://hockeyschtick.blogspot.com/2014/10/new-paper-claims-after-6000-year-pause.html
…Examination of the data from the paper, however, shows the range of proxy sea levels is approximately 10 meters, far too large to discern the tiny ~1.5 mm/yr sea level rise over the past 150 years. The authors instead assume from other published studies of tide gauge measurements that the ~1.5 mm/yr sea level rise over the past 150+ years began at that point in time. Other papers find sea levels rising only 1.1-1.3 mm/yr over the past 203 years, and without acceleration…
Firstly, there has been no acceleration in recent decades despite the ‘HOTTEST DECADE EVAAAAAAH.’ Some argue there has been a slowdown in the rate of sea level rise.
http://www.nature.com/nclimate/journal/v4/n5/carousel/nclimate2159-f1.jpg
http://www.nature.com/nclimate/journal/v4/n5/carousel/nclimate2159-f2.jpg
http://www.nature.com/nclimate/journal/v4/n5/carousel/nclimate2159-f3.jpg
http://www.ncdc.noaa.gov/paleo/pubs/ipcc2007/fig68.jpg
Looking at the NOAA data for SF, there is about 20cm of rise over 150yrs. The authors have noted that they cannot see any variation of less than 20cm in 200yrs. So, if this had happened longer ago, for the authors, it might not have happened at all? That’s what I get from their statement.
So… correlation DOES imply causation. I’m so glad to be learning science from the likes of Worrall. All my previous conceptions of science are being proven wrong by The Lords of Climate Science!
The authors are: Kurt Lambecka, Hélène Roubya, Anthony Purcella, Yiying Sunc, and Malcolm Sambridgea.
Kurt Lambeck, Hélène Rouby, Anthony Purcell, Yiying Sun, and Malcolm Sambridge
Instead of an isostatic rebound adjustment, I think we need an opposing adjustment for subsidence due to bringing all of the concrete in to build large cities near the coastline.
Reblogged this on Public Secrets and commented:
Typical of climate alarmism: declare that something has never happened in a geologically short time-frame, then ignore hard evidence that the phenomenon has occurred again and again, often on a larger scale, in times further in the past, long before Man was spewing CO2 into the atmosphere.
how about the LIA ended…people decided to do something about freezing and starving…and we call that the industrial revolution
The whole premise of this laughable paper is wrong. The Industrial Revolution did not begin 150 years ago. It was already in full swing long before 1864.
It began with harnessing water power in the middle of the 18th century (eg, Kay’s flying shuttle, 1733, leading to Hargreaves’ spinning jenny, 1764), then increasingly switching to coal from 1763-75, with the development of Watt’s improvements on Newcomen’s 1712 steam engine.
Already in 1820-70 progress had advanced to the “Second Industrial Revolution”.
PS: Forests were cut down to keep people warm during the LIA & to build navies. This led to increasing reliance upon coal, demand for which helped fuel the Industrial Revolution. Forests might also have suffered from lower CO2 during the LIA, & a growing population, recovering from the Black Death & wars, needed more farm & pasture land to stave off famine from the deteriorating climate. Population of course had burgeoned during the Medieval Warm Period, making lots of vulnerable potential victims for the plague.
I would argue the IR began around 1700 when coal-fired blast furnaces came into use in England, resulting in a hockey-stick-like rise in iron production (and concurrent price drop). Iron, coal and steam propelled us into the modern world and they all worked to augment each other. Prior to coal it took about 1.25 acres of mature (25 year old) hardwood to make enough charcoal to smelt a ton of iron.
Alan,
I’m happy to comment that coke (coal made like charcoal) was used for roasting malt to brew beer in Derbyshire in 1642, but not employed in a blast furnace for to produce cast iron until 1709, by Abraham Darby, which as you know in Britain sounds the same as “Derby”.
A number of technologies & indeed philosophies came together in 18th century Britain to ignite the Industrial Revolution.
In the late 18th C they started to worry about “Peak Coal”.
Historical E-Book: The Coal Question: An Inquiry Concerning the Progress of the Nation, and the Probable Exhaustion of Our Coal-Mines, Author: William Stanley Jevons
Edition Used: London: Macmillan and Co., 1866. (Second edition, revised)
“ONE of the earliest writers who conceived it was possible to exhaust our coal mines was John Williams, a mineral surveyor. In his “Natural History of the Mineral Kingdom,” first published in 1789, he gave a chapter to the consideration of “The Limited Quantity of Coal of Britain.”
http://www.eoearth.org/article/The_Coal_Question:_Opinions_of_Previous_Writers
Jevons had little time for wind power:
“The first great requisite of motive power is, that it shall be wholly at our command, to be exerted when and where and in what degree we desire. The wind, for instance, as a direct motive power, is wholly inapplicable to a system of machine labour, for during a calm season the whole business of the country would be thrown out of gear.
No possible concentration of windmills, again, would supply the force required in large factories or iron works. An ordinary windmill has the power of about thirty-four men, or at most, seven horses. Many ordinary factories would therefore require ten windmills to drive them; and the great Dowlais Ironworks, employing a total engine power of 7,308 horses, would require no less than 1,000 large windmills!
Coal contains light and heat bottled up in the earth, as Stephenson said, for tens of thousands of years, and now again brought forth and made to work for human purposes.”
He had less time for the idea of taxation to control its use:
“The character of a general tax on coal was truly stated by Robert Bald. “It would unnerve the very sinews of our trade, and be a death-blow to our flourishing manufactories. Were our determined enemy set in council, to deliberate upon a plan to wound us in a vital point as a nation, the advising the imposing of this tax would be the most successful he could possibly suggest.”
And again he says truly, “A small tax on the ton of coal would be a heavy tax on the ton of iron. The whole of our mining concerns depend as to their prosperity upon the abundance and cheapness of fuel, and if the price be increased by means of taxes, the utility of the steam-engine will be greatly abridged.”
Sydney Smith described how a man in former days was taxed at every step from the cradle to the coffin. But through coals we shall be taxed in everything and at every moment.”
How little things change…….
I heard Eric Worrall interviewed on the paper. His main message was that the sea rise was due to expansion from temperature increase. The spin from our warmist Aussie ABC did not really fit Worrell’s rather unexciting observations.
Let’s be childishly optimistic and assume these people can actually determine suitably accurate sea levels over the last 6,000 years. (After all, one same scientific source will give you two different figures for the Earth’s diameter.) Then, let us assume, that in the presence of glacial rebound, variable wave action, tides, underwater volcanoes, reef building, shore erosion, silt deposits, and Leonardo Di Caprio’s rental 482′ yacht, that these people can actually tease out a modest change from that figure over the last 150 years. Accepting the reality of these daunting assumptions I still refuse to believe it was the Industrial Revolution that caused any such rise. Since the cusp of the Industrial Revolution occurred in conjunction with the reforms brought about by the Enlightenment it would seem quite arguable that it was the Enlightenment that is the real villain behind sea level rise. Thus, the true cure for any sea level rise would seem to require an abandonment of Enlightenment values. There seems to be a modest start to that here in the West but we’re nowhere near the level of accomplishment in returning to the Middle Ages that other regions are. We better get a move on or all those zillion dollar beachfront mansions could be at risk.
I think climate science abandoned Enlightenment values a while ago.
Sea level was definitely much higher during the Eemian, without benefit of a Neanderthal Industrial Age. The Eemian was the previous interglacial to our present Holocene, lasting from around 130,000 to 114,000 years ago.
At that time, Scandinavia was an island, the raised beaches in Alaska formed & reefs at Bermuda & the Bahamas, among other evidences, clearly show the higher sea level of that interglacial, warmer & longer lasting than the Holocene so far.
Australia is useful for judging Holocene sea levels, as it wasn’t as weighed down by ice during the Pleistocene as some other continents. Highstands above present msl in the past 6000 years have reliably been found there, although some disagreement exists as to the absolute heights attained.
Palaeogeography, Palaeoclimatology, Palaeoecology (Global and Planetary Change Section), 89 (1990) 143-176 143
Elsevier Science Publishers B.V., Amsterdam
Late Pleistocene and Holocene sea-level change along the Australian coast
Kurt Lambeck a and Masao Nakada b
a Research School of Earth Sciences, Australian National University, Canberra, Australia
b Department of Geology, Faculty of Science, Kumamoto University, Kumamoto 860, Japan
http://www.google.com/url?sa=t&rct=j&q=&esrc=s&source=web&cd=1&ved=0CCAQFjAA&url=http%3A%2F%2Fpeople.rses.anu.edu.au%2Flambeck_k%2Fpdf%2F139.pdf&ei=qZs9VJmeCsruoAT3hYCYCw&usg=AFQjCNE9aWNn5Zp7dielj3XFu29Yp4WHqg&sig2=iGtAGMgDQEO2aksxbzqSog&bvm=bv.77412846,d.cGU
Higher, not “much higher”. That is a factoid. The most tectonically stable coasts indicate 2-4 meters higher. The higher figures are however more politically correct, since they can be used to argue that the West Antarctic Ice-sheet must have collapsed (and is hence likely to to do so again unless we repent), something for which there is, oddly enough, zero actual evidence.
That Scandinavia was an island during the (early) Eemian was not due to higher sea-levels but because the Saalian ice-sheet in western Russia was much larger than the Weichselian, hence the very low-lying area between the Baltic and the White Sea was more depressed by the ice.
I don’t think that anyone knows what happened to the WAIS during the Eemian, but the Holocene has not been as warm as was the last interglacial & so far hasn’t lasted as long. The southern dome of the Greenland ice sheet did apparently partially melt during the Eemian though.
I have seen higher estimates for sea level during the Eemian, at four to six or even five to seven meters higher than now. You may well be right about the motivation for these figures, which are based allegedly upon Alaskan raised beaches & Barbados reefs. It was definitely warmer globally in the Eemian than the Holocene.
The Saalian glaciation was indeed apparently larger than the Weichselian, so would have depressed northern Europe more. Good point.
So, I wonder, what is the sea or “ocean floor” doing while the “sea level” is increasing? – Is anybody checking on that?
A common methodology in cliamte science is to drive models or conclusions using static variables that no rational person would assume is static. In the case of sea level rise, the earth is static, never or minimumly changing and the water it holds is not.
HH Lamb came to different conclusions, based on other scientists’ work of the time.
He found that changes of a metre or two over a few centuries were common, both up and down. He also found that sea levels till about 2000BC were a “metre or two higher than today”, then fell till 500BC before recovering to around today’s level around 400AD.
Sea level fell again before rising to probably a higher level than today during the MWP.
All this is in his book “Climate, History and the Modern World”.
http://notalotofpeopleknowthat.wordpress.com/2014/09/15/hh-lamb-sea-level-changes/
Much of this is borne out around the coast of Britain, where there is direct evidence of higher sea levels in the MWP, despite the land sinking.
Here’s an example:
http://www.norfarchtrust.org.uk/burghcastle
Although southern Britain is falling as northern Britain rebounds from being freed of the weight of its ice sheet & glaciers, East Anglian sea level was higher in Roman times.
From the link:
The changing coast
Map showing Roman coastline
East Norfolk in Roman times
Burgh Castle’s setting has changed a great deal over the last 2000 years. In Roman times sea levels were much higher than they are now and the coastline quite different. The fort would then have stood on the eastern edge not of low-lying grazing marsh, but of an inland ‘Great Estuary’ which covered the whole of present-day Broadland. Large ships might have docked next to the fort and sailed up the rivers Yare, Waveney and Bure to reach Venta Icenorum (Caistor St Edmund), Brampton and other important places.
The main point here is that this turkey has guarranteed his research funding and tenure into the short term future.
Those damned australocpicus and their Flint factories. ….
But wait!
Sea level was higher during the Pliocene, when Australopithecus roamed holding hands, then fell during the Pleistocene, after the Isthmus of Panama formed & Homo habilis started making stone tools, then H. erectus made fire, releasing CO2.
Gavin needs to get busy adjusting those records, too.
So. Should we expect more warming and higher sea levels? Isn’t our current inter glacial still at a lower max temp than prior ones? I’m gonna have add more rocks to our seawall.
Yes, the Holocene is a lot cooler than the Eemian (MIS 5) & at least the interglacial of MIS 11, if not also those of MIS 7 & 9.
Isostatic Rebound is false as the Ice age myth, It is time that we realize that sea llevels were once much higher and covered the earth, Darwin was wrong and as a result the theory of Isostatic Rebound came to us through Agassiz who was also wrong by basing his Isostatic Rebound on Darwins mistake, Woe is us!! is anybody out there listening?
Richard Guy
You’re kidding, right? Sometimes it’s hard to tell.
Agassiz espoused his Ice Age theory in 1837, the same year young Darwin was privately first outlining his theory of descent with modification, which wouldn’t be publicly presented for another 21 years. Agassiz died in 1873, still resisting the theory of evolution.
The evidence in favor of both theories in geology & biology is overwhelming. Glaciations & evolution are scientific facts as well as bodies of theory seeking to explain observed data.
You should be aware that isostasy is an attribute of the continents and a part of the nature of things. And yes, there are isostatic adjustments according to changes in the burdens borne by the earth’s crust.
I must say I’m impressed that Agassiz managed to be inspired to ‘invent´ the Ice-age by Darwin twenty years before the publication of “The Origin of Species”, must have been the first volumes of “Voyage of the Beagle” that did it, or perhaps those papers of barnacle systematics…..
Darwin’s work was published in Volume III of the Beagle narrative, which came out in 1839. So indeed remarkable prescience by Agassiz, who toured formerly glaciated Scotland with the eccentric cleric Buckland in 1840. As noted, Agassiz never was persuaded by Darwin’s theory, which makes his inventing his glacial theory in order to support evolution all the more surprising.
I vote for an “ignore” button to be installed in order to deal with comments like these…
Ancient Rome seaport Ostia Antica: http://www.ostia-antica.org/photo/aerial.jpg
The mention of Rome brought back memories of the drowning Polynesians.
And back to the pesky Little Ice Age cherry pick.
So sea level rise picked up after the end of the Little Ice Age. What the heck does that have to do with the industrial revolution? Why didn’t these chaps go back to the start of the Holocene Hypsithermal? Roman Warm Period?
“Historic variations in sea levels. Part 1: From the Holocene to Romans”
http://judithcurry.com/2011/07/12/historic-variations-in-sea-levels-part-1-from-the-holocene-to-romans/
Beat me to it. This has all been hashed & rehashed on this blog.
Consensus “scientists”, eg Lambeck, et al (2004), challenge Dr. Curry’s conclusions about sea level rise during prior natural Holocene warm periods, such as the Roman, but IMO hers are persuasive:
http://judithcurry.com/2011/07/12/historic-variations-in-sea-levels-part-1-from-the-holocene-to-romans/
The article says: “Of particular note is that during the ∼6,000 y up to the start of the recent rise ∼100−150 y ago, there is no evidence for global oscillations in sea level on time scales exceeding ∼200 y duration or 15−20 cm amplitude.”
Even the IPCC doesn’t think GHG’s perturbed climate much before 1950. If so, sea level rise from 1850-1950 was caused by the end of the LIA. However, sea level rise over 1850-1950 is believed to be about 10 cm (4 inches). So the authors are saying that their methodology is INCAPABLE of detecting important variations in climate – such as the end of the LIA – by their effect on sea level. Therefore, they are unlikely to be able to tell us about the existence of other events such as the MWP, the Roman Warm Period, etc. Likewise, the anthropogenic contribution to SLR – which is less than the 10 cm of SLR since 1950 – would also be undetectable.
It makes sense to be skeptical of any reports concerning sea level during the last interglacial. The Earth’s crust is resting on a viscous mantle than deforms under the weight of ice caps, mountain ranges and continents. The areas covered by ice caps subside (sink) during glacial periods and are still rebounding today. The ocean basins far from ice caps sink under the weight of the extra water present during interglacials. Ocean basins near ice caps rise because of the subsidence of nearby ice covered land. Even if we stay far away from the boundaries between tectonic plates, are any really any “geologically stable” locations on our viscous planet from which we can reliable measure sea level 100,000 years ago to within a few meters?
It can be very educational to look at a few maps. The center of Greenland is below sea level. The usual maps of Antarctica don’t show us where land rises above sea level today. They show the outline of the continent as it would look if the ice cap melted and the land rebounded!
http://en.wikipedia.org/wiki/Greenland_ice_sheet#mediaviewer/File:Topographic_map_of_Greenland_bedrock.jpg
http://commons.wikimedia.org/wiki/File:AntarcticBedrock2.jpg?uselang=en-gb
http://commons.wikimedia.org/wiki/Atlas_of_Antarctica?uselang=en-gb
The internet is such a pesky invention from Gore. Here is NASA living in Never Never Land.
Yet there is NO ACCELERATION in the rate of sea level rise! This is how you know you are being fooled.
Another boring study by ‘Grab a Grant’ Clim-astrologists who just like the charlatans of the 1930s re’d ‘Tea-Leaves’ and put forward their own Interpretation of what they saw.
So just to educate (new) readers to the complexity of ‘Sea Level’ measurement to the nearest Metre watch this short Video.
What is sea level?
Sea level is what we measure with a tidal gauge.
As long as the interglacial continues, sea level should continue rising. The glaciers on the southern third of Greenland are too far south for glaciers to exist. The solar energy in the summer is too strong. It just takes an interglacial lasting 15,000 years or more to melt this ice out.
There is probably something similar in Antarctica and all the mountain glaciers that have remnant influence from the last ice age . They will continue melting out, very slowly, until the interglacial comes to an end in 52,000 years. It just takes lots of time to melt out kms of ice.
I also note that 94 million years ago at the height of the Cretaceous, sea level was 265 metres higher than today and up to 40% of the continents were flooded with shallow ocean. That was because the newly forming Atlantic ocean was much less deep than it is now and the ocean had nowhere to go except onto the Land.
Bill, the Holocene has been a stepdown from early Holocene temperature highs. There is no treason to expect this multi-millenial trend to change, taking the long view.
As far as sea level is concerned, this will present a problem only in locales where subsidence is a problem.
IMO, thermal expansion from more active seafloor spreading, ie submarine volcanism at the ridges, as the continents moved apart also contributed to very high sea levels in the Cretaceous, especially its middle. Plus of course, no ice sheets.
The southern dome of the Greenland Ice Sheet apparently melted completely during the long, hot interglacial of MIS 11, c. 400,000 years ago. Same thing seems to have happened around 800,000 years ago. The Eemian may have been hot enough but didn’t last long enough for the whole dome to melt, but it did partially.
If the Holocene really does persist for another 52,000 years, then earth could indeed experience natural, not man-made, “catastrophic” global warming.
Milo,
Which is correct? The southern dome of the Greenland Ice Sheet apparently melted completely during the long, hot interglacial of MIS 11, c. 400,000 years ago.
or
Ice sheets have one particularly special property. They allow us to go back in time and to sample accumulation, air temperature and air chemistry from another time[1]. Ice core records allow us to generate Ice sheets have one particularly special property. They allow us to go back in time and to sample accumulation, air temperature and air chemistry from another time[1]. Ice core records allow us to generate continuous reconstructions of past climate, going back at least 800,000 years[2]. of past climate, going back at least 800,000 years[2].
How do they get ‘continuous reconstructions’ of 800,000 years if the dome melted 400,000 years ago?
Glaciers in Greenland have been advancing since the Holocene optimum, as shown by many studies. It reached a minimum about 4-5,000 ago and have been mostly growing since then. This includes southern Greenland, see here for example:
http://www.geus.dk/publications/bull/nr27/nr27_p1-68.pdf
http://www.geus.dk/publications/bull/nr14/nr14_p01-78_A1b.pdf
And there are few mountain glaciers that have “remnant influence from the ice age”. Most are neoglacial, i. e. less than 10,000 years old.
I have lived in San Diego for 20 years. I have friends who have lived on the beach nearly 40 years. The water has [now] risen enough for them to notice any rise. Any rise has been of an inch or less. Yet San Diego is not spending tax dollars to study what to do about the ocean rise caused by climate change. It drives me nuts.
I have been visiting the same exact spot on the northern Oregon coast since 1962. In that time, sea level change has not required any humans to do anything, period. ZERO. That is 1/3 of Worrall’s 150 year time period. Zero adaptation necessary. I guess it is still OK to take measured, high frequency, high resolution data and tack it on to low resolution proxy estimates. Mann must be proud.
Since 1950, I’ve experienced no change at Seaside, where my grandfather’s company built the Turnaround & seawall in the 1920s. In fact, the tide surges were higher when I was a kid than now. Anecdotal, I know. Didn’t check the local tide gauge data.
change not to now in my post
Ephesus was established as a sea port about 400 BC. It is now miles from the ocean.
The citadel at Rye, England was built in 1249 on the English channel. It is now over a [mile] from the channel.
Make that more than a mile from the English channel.
Australians again. In an earlier thread today, I made the following observation:
http://wattsupwiththat.com/2014/10/13/another-major-misunderstood-climate-issue-models-underplay-plant-co2-absorption/
“Gary Pearse
October 14, 2014 at 7:17 am
Also, an interesting phenomenon in the life cycle of climate science is emerging. More and more papers are coming out eschewing the alarm and fewer and fewer alarmist papers are coming out (All in Australia? as they battle their defunding – which ironically underscores the political science that it had become). I wondered how this CAGW would all end. It will (be) like covering a linoleum floor with a new layer of linoleum.”
also, the plummy statement in the abstract above of this thread:
“..allowing for isostatic and tectonic contributions, we have quantified the rise and fall in global ocean and ice volumes for the past 35,000 years.”
How did they allow for these contributions? Who did their calculations? Tossing off a complex questions like these with a ho hum pretty well pigeon holes this paper.
Change NOW to NOT is more the norm. John Coleman;
Now I can get on with my grouse.
I want to take issue with Sea Level Guages as a means of measuring sea level based on what we call Isostatic Rebound. Isostatic Rebound is the rising of the landmass due to the absence of the Ice Burden from the last Ice age.SO we install a Sea Level Guage on a Dock or Jetty which is fixed to the landmass and we take occasional readings of the sea level over a prolonged period and expect to get a reliable reading. . Does anyone see anything wrong with that?
Isostatic Rebound is fiction it does not occur. What happens is that the sea is receding and the land mass appears to rise. We all accept sea level as a fixed datum. Rather than admit that sea levels are receding we opt for another fallacy which is, that sea level is rising. So we keep digging ourselves deeper and deeper into the realm of mythology while the facts are staring us in the face.
It is time we debunk the Post Glacial Rebound Theory and the Ice age on which we are fixated. Its all wrong and we are doing science a great injustice because all these theories were first proposed by Charlatans. Richard Guy
Richard,
I see now that you are indeed serious. What do you suppose made all the observed glacier & ice sheet-caused features upon the earth’s surface if not glaciers & ice sheets? Those who first correctly interpreted these features were not charlatans, like today’s CACA advocates, but among the greatest scientists ever to have lived & worked.
Having shown you that your fantasy about Agassiz & Darwin is pure paranoid delusion born of ignorance, I’d like further to awaken you to the reality of ice ages in the history of our planet.
Post-glacial rebound is not “just a theory”. It’s an observable, measurable fact. Just as is the fact that Hudson’s Bay exists because land is lower there due to the weight of the ice sheet which depressed the area.
GEOPHYSICAL RESEARCH LETTERS, VOL. 27, NO. 23, PAGES 3925-3928, DECEMBER 1, 2000
Measuring Postglacial Rebound with GPS and Absolute Gravity
Kristine M. Larson
Department of Aerospace Engineering Sciences, University of Colorado, Boulder
Tonie van Dam
European Center for Geodynamics and Seismology, Luxembourg
Abstract. We compare vertical rates of deformation derived from continuous Global Positioning System (GPS) observations and episodic measurements of absolute gravity. We concentrate on 4 sites in a region of North America experiencing postglacial rebound. The rates of uplift from gravity and GPS agree within one standard deviation for all sites. The GPS vertical deformation rates are significantly more precise than the gravity rates, primarily because of
the denser temporal spacing provided by continuous GPS tracking. We conclude that continuous GPS observations are more cost efficient and provide more precise estimates of vertical deformation rates than campaign style gravity observations where systematic errors are difficult to quantify.
You’re welcome.
I thoroughly agree with milodonharlani. Having grown up literally on the Younger Dryas ice-marginal zone in Scandinavia I know this country has been covered by ice not so long ago. I can see it.
I remember well the first time I visited a major ice-cap (Vatnajökull) and saw for myself all those glacial landforms I know so well actually being created today: sandur fields, marginal deltas, end moraines, ice contacts, ice-dammed lakes, bottom moraine, subglacial rivers….
Don’t try convincing me that the ice-age didn’t happen.
Jerry Henson thanks for mentioning that the Citadel at Rye and Ephesus are now miles from the sea. Sandwich Peterborough and Camber all follow the same pattern Miles from the sea. All the ancient castles and forts in Wales are miles from the sea on which they were original built. All the Roman Roads in Wales which were originally built on the sea are now far inland. The Abbey San Michel on the Normandy Coast of France built six miles out in the English Channel 1000 years ago is now part of the French Mainland. The Castle San Michel Mount at Penzance on the southern tip of Britain was once two miles out from Penzance but now is part of the coastline. All the ancient cities on the Mediterranean are now six miles inland as well as all the old ports on the coast of Italy all six miles inland. Do you begin to see a worldwide pattern???
The State of New Jersey has been selling off the foreshore Atlantic City for millions as soon as the sea retreats and leaves the land behind. They have discovered the receding sea phenomenon purely by accident. They have been using aerial surveys since 1922 and became aware of the growth of the foreshore and the departure of the sea. So the foreshore lands have built the Trump and Playboy hotels. Read my Book “The Mysterious Receding Sea” and see my Vdeos on YOutube. Richard Guy 867-445-8012
Richard Guy
As the sea level varies locally as gravity varies, does anyone know what the weakening of the gravitational field for the last 200 years done to sea level?
OK, a WAG. Less gravity means more air molecules escaping to space, lowering air pressure, causing sea level rise.
Crazy maybe, but just off the top of my head.
Whatever makes you think the gravitational field has weakened?
The sea level in Kakadu National Park used to reach the top of the Arnhem Escarpment, between 400/600 feet where many of the Aboriginal residential and art gallery caves can still be found..
Now Kakadu is mainly floodplain at sea level with the Escarpment a sharp reminder of where the seas once reached.
Perhaps the IPCC can explain?
Sea level was higher during the Cretaceous Period, 144 to 65 million years ago. When the first humans came to Australia c. 60,000 years ago, it was a lot lower than now, thanks to all the water locked up in continental ice sheets.
If it was a lot lower does it follow the Aborigines were living 400 feet above sea level (or even underwater) and how did they reach their caves as , to my knowledge, no traces of 400 feet ladders or steps have been discovered
They either walked or climbed up from below or came down from above. No ladders required. Not that they couldn’t have made ladders. There is no mystery. Please visit the pueblos of the American SW sometime.
They climbed up through 400 feet of water?
There were not 400 feet of water there when people arrived in Australia.
People do live away from the shore you know, Escarpments do not indicate former coastlines. I presume you are from Australia, so you shold have heard of the Great Escarpment, The Illawarra Range and the Darling Range. They are all escarpments, but not old coastlines.
Since 1880 in Sydney harbor the sea level has been rising 0.65 mm/per year, although my friends think otherwise.
http://tidesandcurrents.noaa.gov/sltrends/sltrends_global_station.shtml?stnid=680-140
As the planet heats up, the oceans rise…wheeee!!
http://www.slate.com/blogs/future_tense/2014/10/13/nasa_earth_just_experienced_the_warmest_six_month_stretch_ever.html?wpsrc=fol_tw
Recent research shows the current warm stretch is probably the planet’s warmest in at least 4,000 years. That means global temperatures may have already passed a level that human civilization has never experienced. The sheer size and depth of the world’s oceans means that most of global warming’s extra heat has been stored there. For the last decade or so, atmospheric warming has been playing catch up.
http://www.theguardian.com/environment/2014/oct/14/sea-level-rise-unmatched-6000-years-global-warming
This is arrant nonsense.
For at least 150 years during the Medieval Warm Period, earth was warmer than during any 50 year period of the Modern WP to date.
But the Roman WP was warmer than the Medieval & the Minoan WP was warmer than the Roman. And the Holocene Climatic Optimum was warmer than the Minoan. And the Eemian Interglacial was hotter than any part of the Holocene.
CACA is a crock.
Just who kept the records 4000 years ago and have the y been subjected to “peer review”?
The egyptians did. They recorded the effect of the 4.2 KA event, a major drying and cooling interval c. 4200 years ago, which caused the Yang Shao culture, the Indus culture, the Akkadian civilization, the Eblaite culture and the Egyptian Old Empire to collapse. Egypt finally recovered after a 200-year dark age, which is why we do have records about it. They’re not peer-reviewed though.
Martin,
There has been no acceleration in the rate of sea level rise. There is evidence of a deceleration.
http://www.nature.com/nclimate/journal/v4/n5/carousel/nclimate2159-f1.jpg
http://www.nature.com/nclimate/journal/v4/n5/carousel/nclimate2159-f2.jpg
Martin
October 14, 2014 at 8:00 pm
” The sheer size and depth of the world’s oceans means that most of global warming’s extra heat has been stored there.” [Guardian]
Every day we learn a bit more about the inner workings of the journalist brain.
When referring to the issue of sea-level rise, I prefer to rely on the evidence of Dr Nils Axel Morner, one of the world’s greatest ever experts on sea-level. His extensive research into the matter revealed no discernible rise in sea-level that is of any risk to the planet.
Sea-level rise is not a problem now or in the foreseeable future. It’s simply being used by propagandists to promote alarm about climate change in the hope that governments will sign an international agreement on fossil fuel energy use.
Yeah, that is why the >100 year old tidal gauges in Australia show no change.
Climate creeps are annoying deceivers.
“Of particular note is that during the ∼6,000 y up to the start of the recent rise ∼100−150 y ago, there is no evidence for global oscillations in sea level on time scales exceeding ∼200 y duration or 15−20 cm amplitude.”
Yeah because 130 years ago we started using tide gauges. Isn’t it curious when we shifted from geologic proxies to tide gauges, sea level rise accelerated? Familiar hockey stick from tree rings to thermometers.
As I type I can look out my window and see the harbour, It was built 150 years ago. Looking at the harbour wall I can’t see any evidence that the quay sides have been raised to accommodate any sea level rise. Interesting history for this harbour, Milford Haven, originally built to take the Trans-Atlantic ocean liner trade. Due to muddle and politics Liverpool got that trade and Milford had to make do with fishing.
History and some pictures here: http://www.llangibby.eclipse.co.uk/
The eye can be deceptive. Tide gauge data since 1987 for Milford Haven is available from PSMSL here: http://www.psmsl.org/data/obtaining/stations/1700.php
The trend in the monthly data from January 1988 to Oct 2014 is +7.4 mm/yr, which is slightly over twice the global MSL rise rate. (Filtering out Dec 1989, which is flagged as suspect, the rate rises to 7.8 mm/yr).
If that rate continues, sea levels will be about 2 feet above their current level in Milford Haven by 2100.
Sorry, should be October 2013, not 2014.
Google “sequence stratigraphy”.
http://www.john-daly.com/deadisle/ Go to this to see picture of sea level mark made in 1841 in Tasmania .
I would make two points:
1) Before we worry about “sea level” we should find out whether we need to worry about the high tide level. Has that changed anywhere? And would anyone be more concerned about that than the Dutch? (Many of whom live below sea level.) Are they in a state of national panic? I don’t think so.
2) The surface of the sea conforms to the geoid, which is a surface of constant gravitational potential. This surface is not spherical, has many complex harmonics, and may change over time as the gravitational field distribution of the Earth changes over time. Measurement of the gravitational field harmonics is still a data resource from satellite orbits.
The Dutch are not worried about “sea level.” I think the sea is worried about the Dutch. They literally drained part of the North Sea creating land the size of 14 cities of Paris. 400,000 Dutch now lives on what was once sea.
So tell us Michael; the apparent gravitational pull at any point on the earth surface, would seem to depend not only on the mass distribution around that point, but also on the rotational angular velocity at that location.
So which does the sea surface conform to ? Is equatorial ocean water sitting on a gravitational bulge, so that it tends to flow towards the pole, or is the whole thing in latitudinal equilibrium , so that it doesn’t tend to flow in any direction ?
Sea levels have never risen before which is why the existence of Doggerland must be dismissed as outright fantasy.
The difference between the geoid and ellipsoid is a very slowly-changing variable, dependent primarily (IIRC)on inhomogeneities in crustal density. Hawaii (the big island), for example, corresponds to a relatively drastic change in the geoid-to-ellipsoid height differential over a relatively small ground distance. Other rapid changes are observed near e.g. the Himalayas. But there could be other effects I am ignorant of.