"Assessing recent warming" (2017) put in perspective

ScienceMag (AAAS) published a "rebuttal" of the whole idea of any 21st century pause in global temperature increase a few days ago. The Sceptical blogosphere is awash with indignant posts (and comments) claiming data tampering, or "torturing the data until it confesses". I'm reserving my judgement, except to say that the "pause" has been widely acknowledged by climate scientists, referred to in the last IPCC report (AR5), and concerns surface temperature. The Hausfather et. al. article (not AFAIK peer-reviewed, not that that means much these days) concerns sea surface temperature, a wholly different kettle of fish (I really didn't think of that as a pun, honest!).

ABSTRACT 

Sea surface temperature (SST) records are subject to potential biases due to changing instrumentation and measurement practices. Significant differences exist between commonly used composite SST reconstructions from the National Oceanic and Atmospheric Administration’s Extended Reconstruction Sea Surface Temperature (ERSST), the Hadley Centre SST data set (HadSST3), and the Japanese Meteorological Agency’s Centennial Observation-Based Estimates of SSTs (COBE-SST) from 2003 to the present. The update from ERSST version 3b to version 4 resulted in an increase in the operational SST trend estimate during the last 19 years from 0.07° to 0.12°C per decade, indicating a higher rate of warming in recent years. We show that ERSST version 4 trends generally agree with largely independent, near-global, and instrumentally homogeneous SST measurements from floating buoys, Argo floats, and radiometer-based satellite measurements that have been developed and deployed during the past two decades. We find a large cooling bias in ERSST version 3b and smaller but significant cooling biases in HadSST3 and COBE-SST from 2003 to the present, with respect to most series examined. These results suggest that reported rates of SST warming in recent years have been underestimated in these three data sets.

Here's Figure 1 from the article:

Fig. 1 Comparison of the different ERSSTv3b, ERSSTv4, buoy-only, and CCI SST monthly anomalies from January 1997 to December 2015, restricting all series to common coverage. ERSSTv4 is shown as a broad band for visualization purposes; this band does not represent an uncertainty range. The series are aligned on the 1997–2001 period for comparison purposes. Spatial trend maps are also available in fig. S1, and a similar comparison with Argo data is shown in fig. S2.

What it amounts to, is that the authors have found data series which match their agenda, and found reasons to ignore the other data series which don't. Par for the course these days. As it happens, I've been compiling a set of regional temperature records using GISS data (unadjusted of course), since before Christmas. Just to be different, I'm not ignoring data which doesn't match my agenda, I'm concentrating on large areas of the globe which show interesting results on analysis. More in later posts. For the moment, I thought it might be interesting and amusing to look in detail at the temperature record nearest to President Obama's residence (soon to be vacant for a very short period) and NOAA  headquarters at 1401 Constitution Avenue, Washington DC. The thermometer is at Washington National Airport, just 5km across the Potomac river from NOAA, just inside Virginia.

1880-2016

The 11-year Loess filter shows an uptick around the middle 2000s, after a bumpy "plateau" from 1973. No late 20th C warming evident at all. However, the Loess filter works in a way which includes future change (weighted). If the filter range is constrained to 1880-2009, we get:

1960-2016, Loess range to 2009

Warming began in 2010, after a 27-year "pause". Washington itself would undoubtedly show warming, mostly due to the "Urban Heat Island" effect, but the airport is on the west bank of the Potomac, effectively rural and uncontaminated. A little ironic, that a thermometer just across the river from the nation's capital, seat of a president pledged to "halt global warming" shows no 21st C warming until 2010. The plateau runs from 1974, when he was 12yo - he can't claim responsiblity!

More soon, beginning with Pacific islands. Watch this space.

Where Have all the Real Scientsts gone? Wise words from John A. Knauss

Who on earth is John A. Knauss? He was an oceanographer and was NOAA administrator between 1989 and 1993. It was his foresight which ensured that the effects of the intense El Niño of 1997-8 were adequately measured and analysed.

He added a foreword to a book which I have, written by Bruce C. Douglas and others titled "Sea Level Rise: History and Consequences", published in 2001. Its 270-odd pages are well worth a read if you're interested in a comprehensive and detailed analysis of the mechanics of the tides, and measurement of them. I'll try and find a download link and insert it here. I'll reproduce his foreword without comment apart from saying that he strongly emphasises the problem of uncertainty in understanding and quantifying the effects of the many factors which influence sea level measurement and prediction. One particular sentence of his stands out and is worth quoting right at the start.

Why is the volume of the oceans increasing? Do not expect to find an unambiguous answer in this book.

... and this:

We now believe that the ocean volume has been increasing since the middle of the 19th century at a rate equivalent to raising sea level almost 2 mm/yr, a rate considerably faster than that for the previous thousand years, although how much faster is subject to some uncertainty. That this increase in the rate of sea level rise began well before the rise in our mean atmospheric temperature of recent years gives pause to those who wish to assign its cause to anthropogenic-driven global warming.

I'll repeat my title question - where have all the real scientists (including him) gone?

Foreword to "Sea Level Rise: History and Consequences"

This book describes both clearly and in detail the complexity behind the deceptively simple subject of sea level rise, a topic of considerable scientific interest and increasing economic importance. The concept of sea level rise is quite straightforward. Some 97% of all the water on Earth is now in the oceans; most of the rest is found in glaciers, much of it in Antarctica and Greenland. Some 20,000 years ago at the peak of the last ice age, much more water was in ice and the sea level was more than 100 meters lower than it is today. The glaciers began to melt, the oceans began to fill, and the shorelines were pushed back as the sea level rose. The process continues, and the results are obvious. Archaeologists don aqua-lungs and explore the ancient port of Alexandria. Closer to home and more recent in time, St. Clements island in the Potomac River was a heavily wooded 160 hectares when first occupied by Virginia colonists. Today, some 350 years later it is about 16 hectares and has little in the way of vegetation. Pictures of battered beach houses and hotels eroded by waves after a particularly vicious winter storm moves up the east coast of the United States are a regular feature of our television news.

In the early 1980s when the issue of global warming first grabbed the headlines, I was in Washington as head of the National Oceanic and Atmospheric Administration. One of NOAA's tasks is to predict the tides and maintain this nation's vast array of tide gauges. What effect, I was asked, will global warming have on the change in sea level? It was embarrassing to admit that we really could not say much more than is in the above paragraph. Yes, sea level has risen in the past; we assume it still is rising, but uncertainty remains about how fast it has been rising recently, and thus we are not in a very good position to estimate how fast it might rise in the future. As this volume attests, there continue to be a number of perplexing issues. There is still uncertainty in some areas, but we do know so much more, not just about the changing volume of the ocean, but about yearly and regional variations in sea level and the reasons for them. Even more exciting, the technology now available suggests that we will soon know very much more.

We now believe that the ocean volume has been increasing since the middle of the 19th century at a rate equivalent to raising sea level almost 2 mm/yr, a rate considerably faster than that for the previous thousand years, although how much faster is subject to some uncertainty. That this increase in the rate of sea level rise began well before the rise in our mean atmospheric temperature of recent years gives pause to those who wish to assign its cause to anthropogenic-driven global warming.

Tracking the changing volume of the waters of the ocean, as distinguished from measuring local sea level, is not a simple task. Many traps lie in wait for the unwary, and not long ago many who had examined the problem were skeptical that we would ever achieve useful quantitative information. It has not been easy. Do not expect to examine a half-dozen years of local tide gauge records and derive a useful value. First, at least a 50-year record is required, because there are year-to-year changes (some of which we under-stand, but a number of which we do not) which are likely to bias records that are much shorter. Second, and often more difficult to resolve, the land bordering the sea also moves up and down. In much of Scandinavia the local sea level is dropping because the land is rising (several millimeters a year in places), continuing to rebound from the heavy weight of the glaciers removed several thousand years ago. But isostatic adjustment in those areas formerly under the ice requires some form of viscoelastic compensation in those areas away from the former ice sheets. For example, even if there were no change in the volume of the oceans, we now believe that the sea level would be rising along the east coast of the United States at about 1.4 mm/yr because that is the rate the earth is sinking in this part of the world. As a consequence the actual rise of sea level in this region is nearly double that caused by the change in the ocean volume.

Why is the volume of the oceans increasing? Do not expect to find an unambiguous answer in this book. Perhaps it is the melting of the last of our major ice fields. That is certainly what many believe, but we do not have sufficient information about the volume of ice on either Greenland or Antarctica, let alone its rate of change, to give an unambiguous answer. Perhaps the ocean is getting slightly warmer. If it is, then seawater will expand, and the volume of the ocean will increase although its mass will remain unchanged. An increase of the average ocean temperature (top to bottom) of only a few hundredths of a degree per year is all that is required to raise the sea level a couple of millimeters per year, but we do not have the kind of historical ocean temperature records to either prove or disprove such a possibility.

There may be better data on why humankind's activities of the last half century should be driving sea level lower. We have a good record of the number of dams built in the last half century and the amount of water they control. These dams change the historical flow of water from land to rivers and on to the ocean, and one can make educated guesses whether this should either increase or decrease the rate at which water reaches the ocean. Apparently, the largest single effect is the loss of water from behind the dam which leaches out of the bottom and back into groundwater. This water never makes it to farmland, homes, or industry, nor does it evaporate, later to fall as rain. This water completely bypasses the ocean. A strong case can be made that the rate at which the volume of dammed water is increasing, and thus the rate at which this water is bypassing the usual cycle, is equivalent to a decrease in sea level of possibly many tenths of a millimeter per year.

The rate of change of sea level varies from year to year and place to place. Evidence of past El Niños can clearly be seen in the long-term tidal records of San Diego and San Francisco. Year-to-year changes in the intensity of the wind-driven circulation in the North Atlantic are captured in the yearly changes in mean sea level recorded by tide gauges along the U.S. east coast. With the significant increase in tide gauge accuracy, not the least of which is the removal of the earth movement problem with the availability of GPS, one can expect tide gauges to contribute to an ever-increasing array of geophysical problems.

And finally, if sea level continues to rise, if it is indeed rising at a more rapid rate now than it was a century ago, and if, as some suggest, that rate of rise will increase as a consequence of global warming, what effect will this rising sea level have on society? To those who live in the Ganges delta of Bangladesh, on coral atolls in the Pacific, or below sea level in The Netherlands, this subject holds special interest. One estimate has some 100 million of us living within one meter of sea level. I expect they will be among those most interested in the latest news on this subject.

John A. Knauss

What's the Heartland Institute up to now?

A while ago we had Nils-Axel Mörner and Willy Soon making fools of themselves, claiming that crowds viewing horse-jumping on Atlantic City's Steel Pier had caused temporary subsidence of the pier, and therefore its tide-gauge, easily refuted by reference to other gauges along the north-east coast, which show similar variations. They were trying to show that tide-gauge sites are always unstable, by attempting to show that just one of the 2,000 or more sites worldwide might be unstable. For some reason unknown to me, the Heartland institute thinks that Mörner has something useful to say on sea-levels worldwide. Debunking his outrageous, always changing, and unscientific claims is easier than showing that Bill McKibben can't "do the math". I excoriate Mörner here, here. here, and here.

Now we have James H. Rust, who's

a policy advisor for The Heartland Institute, a retired professor of nuclear engineering, and an outspoken critic of unnecessary alarmism over man-made global warming. He funds several scholarships for students majoring in chemical engineering at Purdue University. He currently is delivering a talk titled “America's Failed Energy Policies and The Reason Why.”

.... suggesting that NOAA has "something to explain" about his straw-measurement of sea-level at Fort Jefferson, Florida. What's a "straw-measurement"? It's like a "straw poll" - rough and ready, and you can't get much rougher than a brick, which is how James does his measuring.

Fort Jefferson in the Dry Tortugas of Florida has an ocean-fed moat that surrounds the large fortress constructed from 1846 to 1875 and never finished. At the single entrance to the fort on its Southern side is an entrance surrounded by a border of marble. Around this border is a brick facade. Sea level height and changes can be measured by the number of bricks above the ocean water line beneath the marble border at the bottom of the entrance.

At 2:30 p.m. February 2, 2013, seven bricks were exposed beneath the fort entrance. These bricks appeared dry and this gave reason to believe the observation was made at high tide. Checking tide data for the Dry Tortugas confirmed 2:20 p.m. was high tide for February 2, 2013.

Checking books in the Fort Jefferson bookstore produced a picture of the fort entrance taken in January 1937. This picture showed all dry bricks above the water line and indicated about 7 and 3/4 bricks were above the water line. A brick and one layer of mortar has a height of about 85 mm and it was estimated the change in Gulf of Mexico water level for the 75-year period was 75 mm. This indicates an annual change in water level at Fort Jefferson of 1 mm per year.

Really? A change in the entire Gulf of Mexico water level estimated from a single observation on one day in 1937 compared with another made at high-tide on one day in 2013, and at a single location? Would temperature measurements made at those two moments be able to tell us whether the temperature there was rising, falling, or remaining much the same over that period? Of course not, whatever the trend, that trend doesn't predict what will occur, or indicate what had occurred, on any particular day. He continues

It may be argued the 1937 picture was not been taken at high tide. If this is true, then the change in sea level would have been less than 1 mm per year. It may be argued the fort is sinking due to its extreme weight. If this is occurring, the sea level rise would be smaller than 1 mm per year.

The National Oceanographic and Atmospheric Association (NOAA) has a map of the world showing sea level changes at hundreds of locations around the world.

The closet [sic] NOAA sea level change data near Fort Jefferson is for Key West, Florida and Cabo San Antonio, Cuba. Both locations are about 70 miles from Fort Jefferson. For the period 1913-2012, Key West has a sea level rise of 2.24 mm per year. For the period 1971-2009, Cabo San Antonio has a sea level rise of 3.30 mm per year.

Sea level rises in both locations reported by NOAA data are considerably greater than rough measurements made at Fort Jefferson. It is left for NOAA to explain this discrepancy on sea level rise for locations so close to each other.

It's not for NOAA to explain anything, as we'll see, and here's a tip from me - don't ever accept an invitation to go sailing in the Gulf with the prof. My Google Maps tracing tool shows Fort Jefferson to be 225 miles NW of Cabo San Antonio, which is the extreme westernmost point on Cuba. His geographical knowledge might be said to be somewhat lacking, in common with Nils-Axel Mörner, as I'll show in a later post (v. soon). Not that geographical knowledge is a real issue here, but a sense of (scientific) direction is.

A little knowledge is a dangerous thing, it's often said, and James has even less than that on this subject. He might have been an excellent professor of nuclear engineering, and he might be "an outspoken critic of unnecessary alarmism over man-made global warming", as I am, but he knows jack sh**, well, you know, about the tides or sea-level in general., and in the Gulf of Mexico in particular. Let's educate him a little.

There are two high tides a day (more accurately every 24h 25.2m), in this part of the Gulf of Mexico, and they follow what is, apparently unbeknown to James, the lunar tidal cycle, dominated by the gravitational pull of the Moon, modulated by that of the Sun. Not all places worldwide have two tides a day; some have only one, and some have two tides during part of the cycle, and one for the remainder. In a few areas, like the central Baltic, there are no tides whatsoever.

NOAA, who he says has "something to explain", has convenient tide data pages for their gauge sites. Here's the one for Feb 2-3 2013 at Key West.

Water level for 2-3rd Feb 2013 at Key West, Florida                                 Source: NOAA

Note that the actual tide was a little over 6" or about 16cm above that predicted. Brick-centric observations by James indicate that there was a rise of some 7.5cm over the 76-year period (2013-1937 = 76, not 75). That means of course, that had the tide followed orders, the 2013 level would have been less than the 1937 picture showed. How so? Is the sea-level here, and at Key West, an excellent proxy, not rising? Indeed it is, as the NOAA plot (thoughtfully not provided in the blog post for our edification) shows

Key West, Florida 1913-2012                                                                     Source:NOAA

This gives the impression that It's not possible for any average monthly level in 2013 to be less than that in 1937, but that's because this chart has had the "average seasonal cycle" removed (top left). It's not raw data, and it's done to make the overall picture clearer. Here's the raw plot

Key West, Florida 1913-2011                                                                Data source: PSMSL

Now it's obvious that many months in the middle-thirties had higher averages than many months in the entire period since. Here's how the data for February varied. I've highlighted Feb. 1937.

Key West, Florida; February average 1913-2011                                Data source: PSMSL

January 1937 was lower at 7055mm, but that's still higher than many months since, January 2009 for example at 7029 mm.

Here's a NOAA plot from 2nd Feb to yesterday, 17th Feb.

Water level for 2nd-17th Feb 2013 at Key West, Florida                            Source :NOAA

It should be clear by now that any single observation is just that, even when compared with another single observation, whether measured in metres, feet and inches or bricks. Rusts's post was titled "A New Sea Level Rise Data Point: Not Too Serious", and it's just that, a data point, but it reveals he's missing the point. He's right - it isn't too serious, but he's not right because of any observations or deductions he's made. He's right because the trend of sea-level rise at Key West, which he's unaware of, but which I already had in my spreadsheet for Key West (as in most others I maintain) shows this

Key West: trend in mm/year from 1913 to year on lower axis           Data source: PSMSL

..... that there's been no change in trend over the last four decades. Also, GPS at Key West Naval Air Station shows that the site is subsiding at about 0.63 mm/year, which means that true sea-level there is rising at about 1.5 mm/year. Subsiding due to crowds flocking to see the 'planes take off and land, maybe? Heavier modern 'planes? The fact that this area of the Gulf eastward including Florida is subsiding? Need any more hints?

I'm "an outspoken critic of unnecessary alarmism over man-made global warming" too, but I make observations on what I know something about, and when I see an erroneous or unscientific analysis or conclusion by anyone I'll make it my business to point out any flaws. Sea-level at any spot is modified by rate of change, wind direction, barometric pressure, and sea temperature. Conclusions by retired professors of nuclear engineering on topics outside their sphere of expertise are clearly modified by preconceived notions, and a total lack of knowledge of what they're writing about.

More Signs Of Accelerating Sea Level Rise - what signs?

Maybe it's me, maybe there's some other meaning of the word "signs" I was previously unaware of. Maybe Forbes writer John McQuaid picked no.243 instead of no.244 from his collection of alarmist headlines. I leave you to judge - here's the entire piece.

More Signs Of Accelerating Sea Level Rise

Evidence continues to mount that recent estimates of sea level rise from global warming were wrong, and that the potential inundation to come may be much worse than previously contemplated, possibly exceeding an average of 3 feet worldwide. This from a new study published in Nature Climate Change focusing on the latest opinions of scientists studying the world’s largest ice sheets in Greenland and Antarctica, where recent, unexpectedly fast melting has raised alarms:

The study found that the ice sheets are likely to contribute a median estimate of 29 centimeters (11.4 inches) of sea level rise by 2100, with a 5 percent chance that it could exceed 84 centimeters (33 inches). When combined with other contributors to sea level rise, such as melting mountain glaciers and thermal expansion of seawater, this implies a “conceivable risk” that sea levels could rise more than 1 meter by 2100.

What’s significant here is that the 1 meter figure, once a highly unlikely, worst-case scenario, has moved decisively into the realm of possibility. It’s still unlikely, according to the scientists surveyed. But current alarming trends mean it has become a lot less so. That said, a lot of uncertainty remains; scientists are unclear on why the melting has accelerated, or if that trend will continue. But given what we’ve seen so far, it’s the official IPCC estimates for sea level rise will likely be revised upward, putting additional pressure on governments to act.

It’s still early in the century, of course, and some urban areas are starting to grapple with changes to infrastructure, coastal settlement, and other issues. But the evidence suggests that the march of disaster will probably continue to outrun attempts to prevent it.

The last sentence of the abstract of the "new study" says

On the critical question of whether recent ice-sheet behaviour is due to variability in the ice sheet–climate system or reflects a long-term trend, expert opinion is shown to be both very uncertain and undecided.

So John McQuaid has decided that "the potential inundation to come may be much worse than previously contemplated" even though the scientists themselves say they don't know whether the trends they identified did indeed reflect a long-tern trend or (natural) variability in the ice-sheet climate system. They updated the ice-sheet component in predictions in AR4 - they didn't validate them. They even say "It's still unlikely" but John (Now working on a book about the science of taste, to be published by Scribner) McQuaid knows better because "current alarming trends mean it has become a lot less so".

What trends (note the "s")? WashPo bleats "2012 hottest year on record in contiguous U.S., NOAA says". Apparently the egg-heads (hard-boiled in the extreme heat perhaps) at NOAA "described the data as part of a longer-term trend of hotter, drier and potentially more extreme weather". Hang on - I was promised "more signs" and I'm served with just one. I was assured of "alarming trends" but have a single dusted off, polished-up old (but somehow confirmed) trend dished up? Aren't short-servings illegal in the good-old US of A?

Those egg-heads seem to think that one warm year "confirms a trend". Don't take any advice on stock-market investments from these guys - they'd have you shivering and hungry on a street-corner in no time flat. Wait - there are still people hungry and shivering on street corners since Sandy struck NY. Sandy confirmed a trend too - a reducing trend in land-falling hurricanes on the eastern seaboard. Short-order writer McQuaid takes this weeks cake for hyperbole. I'd better rephrase that - hyperboles - he wouldn't understand that word if I omitted the "s".

High and Dry in San Francisco - NOAA's Ark?

Here's a beach pic at the Presidio, north of San Francisco, not that far from the Golden Gate bridge (seen on the extreme left).

Weather's a bit dull, but there's plenty of sand on the beach. Here's a sunnier view.

The small hut on the right contains the tide gauge for San Francisco. Both pics are from the NOAA station information page for that gauge. Based on the first pic, how would you rate the chances of the gauge registering low water accurately?