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Part 490, Projected Sea-level Rise - Express Terms

6 NYCRR

Chapter IV Quality Services

Subchapter I Climate Change

Part 490 Projected Sea-Level Rise

490.1 Purpose

This Part establishes science-based projections of sea-level rise for New York State's 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.

490.2 Applicability

This Part applies to consideration of sea-level rise by the Department, other State agencies, and applicants for relevant permits, approvals, and funding in the context of programs specified in the Community Risk and Resiliency Act.

490.3 Definitions

For the purposes of this Part, the following definitions apply:

(a) '2020s'. The years 2020 through 2029.

(b) '2050s'. The years 2050 through 2059.

(c) '2080s'. The years 2080 through 2089.

(d) 'Baseline level'. The average level of the surface of marine or tidal water over the years 2000 through 2004.

(e) 'ClimAID model outputs'. Projections based on the outputs of global climate models, downscaled to New York, and additional information, including information to account for anticipated changes in the rates of ice melt that cannot yet be more rigorously included in quantitative models.

(f) 'Community Risk and Resiliency Act'. Chapter 355 of the Laws of 2014.

(g) 'Department'. The New York State Department of Environmental Conservation.

(h) 'High-medium projection'. The amount of sea-level rise that is unlikely (the 75th percentile of ClimAID model outputs) to be exceeded by the specified time interval.

(i) 'High projection'. The amount of sea-level rise that is associated with high rates of melt of land-based ice and is very unlikely (the 90th percentile of ClimAID model outputs) to be exceeded by the specified time interval.

(j) 'Long Island Region'. The marine coast of Nassau and Suffolk counties.

(k) 'Lower Hudson-New York City Region'. The main stem of the Hudson River, south from the mouth of Rondout Creek at Kingston, New York, and the marine coast of the five boroughs of New York City and the Long Island Sound in Westchester County.

(l) 'Low-medium projection'. The amount of sea-level rise that is likely (the 25th percentile of ClimAID model outputs) to be exceeded by the specified time interval.

(m) 'Low projection'. The amount of sea-level rise that is consistent with historical rates of sea-level rise and is very likely (the 10th percentile of ClimAID model outputs) to be exceeded by the specified time interval.

(n) 'Medium projection'. The amount of sea-level rise that is about as likely as not (the mean of the 25th and 75th percentiles of ClimAID model outputs) to be exceeded by the specified time interval.

(o) 'Mid-Hudson Region'. The main stem of the Hudson River, from the federal dam at Troy to the mouth of Rondout Creek at Kingston, New York.

(p) 'Sea-level rise'. The increase in the average level of the surface of marine or tidal water for the specified geographic region.

490.4 Projections

The tables in subdivisions (a), (b), and (c) of this section establish projected sea-level rise for the specified geographic region relative to the baseline level.

(a) Mid-Hudson Region

Time Interval Low
Projection
Low-Medium
Projection
Medium
Projection
High-Medium
Projection
High
Projection
2020s 1 inch 3 inches 5 inches 7 inches 9 inches
2050s 5 inches 9 inches 14 inches 19 inches 27 inches
2080s 10 inches 14 inches 25 inches 36 inches 54 inches
2100 11 inches 18 inches 32 inches 46 inches 71 inches

(b) New York City/Lower Hudson Region

Time Interval Low
Projection
Low-Medium
Projection
Medium
Projection
High-Medium
Projection
High
Projection
2020s 2 inches 4 inches 6 inches 8 inches 10 inches
2050s 8 inches 11 inches 16 inches 21 inches 30 inches
2080s 13 inches 18 inches 29 inches 39 inches 58 inches
2100 15 inches 22 inches 36 inches 50 inches 75 inches

(c) Long Island Region

Time Interval Low
Projection
Low-Medium
Projection
Medium
Projection
High-Medium
Projection
High
Projection
2020s 2 inches 4 inches 6 inches 8 inches 10 inches
2050s 8 inches 11 inches 16 inches 21 inches 30 inches
2080s 13 inches 18 inches 29 inches 39 inches 58 inches
2100 15 inches 21 inches 34 inches 47 inches 72 inches
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