{"id":305461,"date":"2024-03-01T17:34:12","date_gmt":"2024-03-01T16:34:12","guid":{"rendered":"https:\/\/climatescience.press\/?p=305461"},"modified":"2024-03-01T17:34:15","modified_gmt":"2024-03-01T16:34:15","slug":"new-york-state-sea-level-rise-fantasy-as-law","status":"publish","type":"post","link":"https:\/\/climatescience.press\/?p=305461","title":{"rendered":"New York State Sea Level Rise:\u00a0 Fantasy as Law"},"content":{"rendered":"\n
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From Watts Up With That?<\/a><\/p>\n\n\n\n

Opinion by Kip Hansen \u2014 28 February 2024<\/p>\n\n\n\n

In the United States, both Federal and State agencies make pseudo-laws by formalizing \u201crules\u201d which have the effect of law but are not written by or voted on by the legislators which have the responsibility to make law.<\/p>\n\n\n\n

We see this in the fight over CO2<\/sub> and PM2.5 rules from U.S. Federal agencies like the EPA.  At the Federal level, the rule making process takes more than a year, usually two or more and includes Public Comment periods.  Rules are difficult to undo \u2013 and require the same lengthy process to make a new rule to override the old. <\/p>\n\n\n\n

New York State, currently big on the Climate Crisis, has just proposed a new rule as follows:<\/p>\n\n\n\n

Proposed Action: Amendment of Part 490 of Title 6 NYCRR.<\/em><\/p>\n\n\n\n

Statutory authority: Environmental Conservation Law, section 3-0319<\/em><\/p>\n\n\n\n

Subject: Science-based State sea level rise projections. \u2014 Purpose: To establish a common source of sea-level rise projections for consideration in relevant programs and decision-making.<\/em><\/p>\n\n\n\n

In plain English, the NY State Department of Environmental Conservation (NYS DEC) proposes a common source of Sea Level Rise Projections <\/strong>to be used statewide for program planning and decisions making.  This sounds good, right?  Can\u2019t have all these different government programs and politicians using different data \u2013 that would be a mess.<\/p>\n\n\n\n

Let\u2019s see what they are mandating through this rule:<\/p>\n\n\n\n

490.1 Purpose: <\/em>This Part establishes science-based projections of [sea-level rise] sea level rise for New York State\u2019s tidal coast, including the marine coasts of Nassau, Suffolk and Westchester counties and the five boroughs of New York City, and the main stem of the Hudson River, north from New York City to the federal dam at Troy.<\/em><\/p>\n\n\n\n

Readers unfamiliar with New York State geography can look at this map of NY State \u2013 the above paragraph covers all the coastal sections of Long Island, Atlantic and Long Island Sound, and the Hudson River, which is tidal, all the way to Troy, which is north of Albany:<\/p>\n\n\n

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So, we see that besides the usual coastal areas, where we would expect tides, the Hudson River itself is tidal all the way north to \u201cthe federal dam at Troy\u201d, which is 160 miles north of The Battery which sits at the southern tip of Manhattan Island (see inset lower right). \u00a0\u00a0<\/p>\n\n\n\n

The geography dictates that all of the tides up the Hudson River are determined by the tides at the Battery.<\/p>\n\n\n

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So, if we want to know how much sea level rise there has been in the past for Manhattan and all points north on the Hudson River, we must look to the tide gauge at The Battery.\u00a0 We would be in luck, as that is one of the longest continuous tide gauge records in the United States and is coupled to a continuously operating GPS stations, which allows correction of the tide gauge record for the \u00a0vertical land movement (VLM) of the rock to which the tide gauge is attached.\u00a0 Subtracting the VLM from the\u00a0Relative Sea Level Rise<\/a>\u00a0(RSLR) apparent in the Tide Gauge Record, \u00a0we can determine eactly how much the sea surface itself has risen.<\/p>\n\n\n\n

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According to NOAA\u2019s tide gauge record, The Battery has a long-term, nearly-perfectly linear record of Relative Sea Level Rise over 167 years of 2.92 mm\/yr.  It can be highly variable month-to-month.  We can safely just say 3 mm per year<\/strong> and be close enough.<\/p>\n\n\n\n

How much of that is subsidence of the structure on which the tide gauge is mounted?  According to the latest study<\/a> [Wu, P.-C., Wei, M. (M. ), & D\u2019Hondt, S. (2022). \u201cSubsidence in coastal cities throughout the world observed by InSAR\u201d. Geophysical Research Letters <\/em>] NY City\u2019s The Battery sees VLM of -1.21 mm\/yr.  That is subsidence, downward land movement, of over 40% of the recorded Relative Sea Level Rise, leaving  1.69 mm\/yr of upward movement of the actual surface of the sea per year.  That 1.69 is very close to the standardly cited Global Sea Level Rise figure for the 20th Century of 1.7 or 1.8 mm\/yr.  (opinions vary \u2013 see NOAA here<\/a>.)<\/p>\n\n\n\n

Note that this latest VLM finding is very close to that found in the seminal paper by Snay et al. in 2007<\/a> of -1.35 mm\/yr for The Battery.<\/p>\n\n\n\n

The subsidence at The Battery will not necessarily be reflected in the tidal values up the Hudson River, as coastal New York is thought to be subsiding at a faster rate than areas inland, and the \u201chinge point\u201d for crustal rebound on the Hudson River is around Kingston, NY, which is about 95 miles north of The Battery, north of which the land begins to rise instead of subside.  <\/p>\n\n\n\n

Nonetheless, for our purposes today, when talking about potential Sea Level Rise in the upriver reaches of the Hudson River, we can use 3 mm\/yr as the upper bound and 1.7 mm\/yr as the lower bound for Sea Level Rise on the tidal Hudson based on historical records<\/em> corrected for VLM.<\/p>\n\n\n\n

The proposed NY State rule calls for replacing the previously used \u00a0ClimAID projections, which had been updated in 2014, in this report:<\/p>\n\n\n\n

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which can be downloaded here<\/a>.<\/p>\n\n\n\n

Let\u2018s see what the updated projections are as of 2014.<\/p>\n\n\n

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The new rule calls for replacing the projections from the ClimAID 2004 report as updated in 2014.  This newer report updated the base period, changing the base period from 2000-2004  to the twenty years between 1995-2014, but gives no numerical metric \u2013 it doesn\u2019t state what they were to use for the average sea level for that time period.    There are so many different methods of determining that base period metric that I will simply fallback on referring to the tide gauge record at The Battery. <\/p>\n\n\n\n

Using the long-term tide gauge record, we see an unchanging trend of 2.9 mm\/yr.  The trend for the base period appears to be the same when looking at the whole record. (Technically, using the recorded monthly values, from Jan 1995 through Dec 2014, the linear trend is down\u2026which is what happens when selecting just a small portion of a long-term record).<\/s>  The previous sentence is an error \u2013 depending on and sensitive to the exact starting and ending dates for the base period (Jan or Dec 1995 and Jan or Dec 2014) the trend is either close to 2.9 mm\/yr or decidedly flatter.<\/p>\n\n\n\n

All of that adds up to this:  The least-wrong projection of future sea level rise for The Battery would be \u201cmore of the same\u201d \u2013 about 3 mm\/yr. \u2013 and, if one was overcome by a sudden attack of over-cautiousness, \u201cmaybe a little more.\u201d<\/p>\n\n\n\n

If we wish to include global warming\/climate change in our forecast, then we must do so from one of the following IPCC dates for the start of Climate Change:   1890,  1950 (mid-20th<\/sup> century) or 1979 [IPCC AR6<\/a>].  It is obvious from the NOAA Tide Gauge Record of The Battery that the sea level rise rate did not change at any of those dates but has rather remained stubbornly steady at the stated about 3 mm\/yr or 30 mm per decade or 300 mm (about 12 inches) per century.<\/p>\n\n\n\n

What does the new rule say planners in NY State must consider?  For all of these projections which are from the base period 1995-2014, the date of the report?<\/p>\n\n\n\n

The previous version, supposed to be based on the updated NYSERDA report, had these:<\/p>\n\n\n\n

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The first chart above is from the NY State Register version of the new rule, however, despite claiming that the projections are from the New York State Energy Research and Development Authority<\/a> <\/em>(NYSERDA) 2014, they are not the same.  The second chart is the equivalent chart from NYSERDA (2014).  Note that the dates are different and that even for the Low Projection, the new rule adds 10 extra inches<\/strong> (from 15 to 25) to projected SLR in NYC by 2100 without any explanation for the differences from the NYSERDA report.<\/p>\n\n\n\n

It has taken a very deep dig to discover that the SLR projections in the new rule are derived from an Interim Version<\/em> of a report that is to be cited as : Stevens, A., & Lamie, C., Eds. (2024). New York State Climate Impacts Assessment: Understanding and preparing for our changing climate<\/a>.<\/em>  (All the available .pdf files are watermarked INTERIM PUBLICATION<\/em>.)<\/p>\n\n\n\n

I\u2019ll come back to how these projections came to be so exceptionally high.<\/p>\n\n\n\n

If we just stick to SLR trends, so how much SLR do we need to experience at The Battery to see 6 inches of SLR between 2014 and 2039?  That\u2019s 25 years to see 152 millimeters of SLR; just about exactly 6 mm\/yr. <\/p>\n\n\n\n

Low Projection<\/u>:  <\/strong> Even for the low projection, we would have had to seen twice the rate of SLR, every year since 2014 and every year up to 2039,  as we have actually experienced.  In the 9 years since 2014, we have only had 27-30 mm of SLR leaving 122 mm to be achieved in the next 15 years which would be a rate of a little over 8 mm\/yr, nearly triple the current rate<\/strong>.  Likewise, for the 2100 low projection, a rate of about 8 mm\/yr for the rest of the century would be required. <\/p>\n\n\n\n

High Projection<\/u><\/strong>:  <\/strong>The projection calls for 13 inches or 330 mm between the years 2014 and 2039 \u2013 which would require a rate of SLR of 13 mm\/yr<\/strong>.  Since it is now 2024, we have only about 15 years left to see the remaining 300 mm (we have already seen 30) which requires 20 mm per year or 8\/10th<\/sup> of an inch, each year, for the next 15 years.<\/strong><\/p>\n\n\n\n

They are just making this rule now, today, this week. <\/strong><\/p>\n\n\n\n

I would think that those proposing this rule would realize that if they have not seen any increase in SLR rate in the last decade, 2014 to 2024, that it would require something truly extraordinary to see the rate of SLR double or triple over the next 15 years.  And these multiples are just for the Low Projection.<\/p>\n\n\n\n

When considering the High Projections to 2100<\/strong>, we find that the projected rate of SLR used in the new rule are the same 20 mm\/yr for the 85 years from 2014-2100.  <\/strong>But again, that would have required 20 mm\/yr for the last decade as well, which we have not seen.<\/p>\n\n\n\n

In short, something is seriously wrong with the projections of Sea Level Rise in this new rule.\u00a0 They are not based on the 2014 NYSERDA report, but on the new, apparently not yet finalized,\u00a0New York State Climate Impacts Assessment (2024)<\/a><\/em>.\u00a0 I\u2019ll give you a peek at the full projection from this report for The Battery (click on it for\u00a0a single page .pdf download<\/a>):<\/p>\n\n\n\n