24

NOAA Technical Report NMFS 24

Temperature Conditions in

the Cold Pool 1977-81:

A Comparison Between

Southern New England and

New York Transects

Steven K. Cook

February 1985

u.s. DEPARTMENT OF COMMERCE

National Oceanic and Atmospheric Administration

National Marine Fisheries Service
NOAA TECHNICAL REPORTS NMFS

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Spriogfield. VA 22161.
NOAA Technical Report NMFS 24

Temperature Conditions in

the Cold Pool 1977-81:

A Comparison Between

Southern New England

and New York Transects

Steven K. Cook

February 1985

u.s. DEPARTMENT OF COMMERCE

Malcolm Baldrige, Secretary

National Oceanic and Atmospheric Administration

John V. Byrne, Administrator

National Marine Fisheries Service

William G. Gordon, Assistant Administrator for Fisheries
The National Marine Fisheries Service (NMFS) does not approve, recommend or endorse any propriety product or proprietary material mentioned

in this publication. No reference shall be made to NMFS, or to this publication furnished by NMFS, in any advertising or sales promotion which

would indicate or imply that NMFS approves, recommends or endorses any

proprietary product or proprietary material mentioned herein, or which has

as its purpose an intent to cause directly or indirectly the advertised product to be used or purchased because of this NMFS publication.
CONTENTS

General description of the cold pool. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . I

Methods.................................................................................................. 2

Results. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3

Numerical analysis. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5

Conclusions. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7

Acknowledgments. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7

Literature cited ... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7

Figures

1. Locator chart showing transect envelopes for Southern New England and New York. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2

2. Plot of standard bathymetry along the Southern New England and New York transects. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2

3. Plot of average bottom temperature on depth-time grid for 1977-81 along the Southern New England transect. . . . . . . . . . . . . 4

4. Plot of average bottom temperature on depth-time grid for 1977-81 along the New York transect. . . . . . . . . . . . . . . . . . . . . . . 4

5. Plot of maximum and minimum observed bottom temperature at 60 m depth for Southern New England transect, New York

transect, and composite of both transects 6

Tables

1. Bathymetric differences between Southern New England and New York. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2

2. Annual distribution of XBT's collected on the Southern New England and New York transects . . . . . . . . . . . . . . . . . . 3

3. Weighted mean temperature and percent of depth-time "area" covered by water of< lOoC 5

4. Derived maximum, minimum, and average of bottom temperatures at60 m depth and their timing in Julian Days. . . . . . . . . . 6

5. Comparison ofJulian Day and decad/pentad units and approximate months for both warming and cooling periods. . . . . . . . . 7

Appendix Figures

1. Plot of bottom temperature on depth-time grid along the Southern New England transect for 1977 .. . . . . . . . . . . . . . . . . . . . . 9

2. Plot of bollom temperature on depth-time grid along the Southern New England transect for 1978 . . . . . . . . . . 10

3. Plot of bollom temperature on depth-time grid along the Southern New England transect for 1979 . . . . . . . . . . . . . . . . . . . . . . 11

4. Plot of bottom temperature on depth-time grid along the Southern New England transect for 1980 . . . . . . . . . . . . . . . . . . . . . . 12

5. Plot of bottom temperature on depth-time grid along the Southern New England transect for 1981 13

6. Plot of maximum bottom temperature on depth-time grid for 1977-81 along the Southern New England transect. . . . . . . . . . . 14

7. Plot of minimum bollom temperature on depth-time grid for 1977-81 along the Southern New England transect. . . . . . . . . . . 15

8. Plot of bollom temperature on depth-time grid along the New York transect for 1977 16

9. Plot of bollom temperature on depth-time grid along the New York transect for 1978 17

10. Plot of bOllom temperature on depth-time grid along the New York transect for 1979 18

11. Plot of bOllom temperature on depth-time grid along the New York transect for 1980 19

12. Plot of bollom temperature on depth-time grid along the New York transect for 1981 20

13. Plot of maximum bottom temperature on depth-time grid for 1977-81 along the New York transect. . . . . . . . . . . . . . . . . . . . . 21

14. Plot of minimum bollom temperature on depth-time grid for 1977-81 along the New York transect. . . . . . . . . . . . . . . . . . . . . 22
•
Temperature Conditions in the Cold Pool 1977-81:

A Comparison Between Southern New England and

New York Transects

STEVEN K. COOK1

ABSTRACT

Expendable bathythermograph data collected by the Ships of Opportunity (SOOP) - Ocean Monitoring Program are analyzed for seasonal and inter-annual variations of the cold pool. Two major SOOP transects within

the Middle Atlantic Bight (Southern New England and New York) have been analyzed for the years common to

both (1977-81). During the years 1977-81, over 200 transects were occupied, and almost 3,000 XBT's were

droppe<l.

Results show that the cold p'Jol is formed with the onset of spring warming and persists until fall overturn,

is consistent year to year in both area and weighted average annual temperature, and advects water from the

northeast to the southwest. Results also show a 100-d lag in minimum temperature between the Southern New

England and New York transects. DitTerences in bathymetry between the two transects and their inOuence on the

cold pool are also discussed. Plots of average (1977-81) bollom temperature for both transects are discussed and

show consistent annual weighted mean temperature and areas. Bollom temperature plots for individual years, as

well as maximum and minimum bollom temperature plots, are presented as Appendix figures.

GENERAL DESCRIPTION OF THE

COLD POOL

The cold pool, so named by Bigelow in 1933, is a continuous

subsurface water type located on the continental shelf bottom between Georges Bank to the northeast and Cape Hatteras to the

southwest. This feature was referred to as "remnant winter water"

by Bigelow (1933), Ketchum and Corwin (1964), and Whitcomb

(1970) who believed it to be formed from the winter cooling of

mixed Middle Atlantic Bight shelf water. The cold pool feature

has been traced in the north to the eastern edge of Georges Bank

and into the Gulf of Maine (Colton et al. 1968; Limeburner et al.

1978) where temperature and salinity relationships suggest a

possible source (Beardsley et al. 1976; Hopkins and Garfield

1979). To the south the cold pool feature has been traced past the

offing of Chesapeake Bay to Cape Hatteras where three major

water masses (shelf, slope, and Gulf Stream) converge.

The cold pool becomes an identifillble feature each year with

the onset of spring surface warming and thermal stratification

(generally in late April to early May) and lasts throughout the

summer into early fall, until the normal seasonal overturn in

October-December, but mostly in November, mixes away the vertical density structure and the water column again becomes

isothermal.

Our soap - Vertical Temperature sections show that the cold

pool normally covers an area on the bottom between the 40 and

110m isobaths (~ 20-60 fathoms), an area of approximately

88,000 km2 between Georges Bank and Cape Hatteras. The

aver;ge thickness of the feature is about 35 m and extends from

the bottom to the base of the thermocline (within 20-30 m of the

surface). This represents a volume of about 3,100 kmJ

Wright (1976), from a volumetric analysis, calculated the total

volume of shelf water within the Middle Atlantic Bigh! at about

I Northeast Fisheries Center Atlantic Environmental Group, Nalional Marine

Fisheries Service, NOAA. RR7, South Ferry Road, Narragansell, RJ 02882.

11,000 km3 . Thus, the cold pool represents about 28% of the total

volume of shelf water within the Middle Atlantic Bight. •

The cold pool is a slowly moving feature (by virtue of its bathymetric location) when compared with the more active zones of

mixing both seaward (shelf water/slope water front) and shoreward (tidal), and it has a general southwesterly flow of about 1

cm/s (0.02 kn) to 5 cm/s (0.10 kn), according to Mayer et al.

(1979) and Houghton et al. (1982), respectively. However, it is

acted on by several processes, either singly or simultaneously,

some of which are as follows:

Wind Events can cause upwelling near shore, moving the shoreward edge of the cold pool toward the beach and sometimes even

into the surf zone (Hicks and Miller 1980). Even relatively mild

wind events « 20 mph - 8.9 m/s) with the appropriate directional change can cause a significant change in sea surface

temperature. mixed layer depth, and shoreward movement of the

cold pool (Cook and Gardner 1978). The same wind events, if persistent enough. also can influence the offshore edge of the cold

pool by forcing the shelf water/slope water surface front to move

seaward (Csanady 1978).

Gulf Stream Rings migrating along the shelf edge to the southwest through the Middle Atlantic Bight can cause perturbations in

the subsurface shelf water/slope water front. Advection of upper

slope water (> 12°C) shoreward over the edge of the continental

shelf can sometimes move the cold pool off the bottom and cause

it to bulge seaward, eventually breaking off into slope water as

parcels of shelf water. This process has been referred to as

"calving" (Whitcomb 1970; Wright 1976).

Bathymetric Influences such as shoals (Nantucket), together with

strong tidal currents, can mix away the cold pool locally. Fourteen

major submarine canyons intersect the cold pool at several locations. from Corsair Canyon at the eastern edge of Georges Bank to

Norfolk Canyon at the southern end of the Middle Atlantic Bight.

Flow in the canyons can cause movement in the position of the

cold pool. According to Mooers et al. (1979), down canyon trans-
port of cold pool water was observed along the southwestern side

of Wilmington Canyon, possibly leading to a calving event. In

contrast to this, Han and Niedrauer (1981) observed that cold pool

water did not sink into the Hudson Shelf Valley, but rather stayed

at the same level as on the surrounding shelf. The proximity of the

Gulf Stream at the southern edge of the cold pool (Cape Halleras)

entrains both surface shelf water and subsurface cold pool water

(Ford et al. 1952; Fisher 1972; Kupferman and Garfield 1977),

and limits its southern extent.

A standard bathymetric profile was derived for each route (see

Fig. 2) that roughly bisects the transect envelopes shown on

Figure 1. The transect envelopes shown on Figure 1 are, of course,

diagrammatic and represent the worst case deviations from the

"standardized" route. It should be pointed out that the majority of

the actual transects collected were much closer to the "standardized" route than the outer edges of the envelope.

Comparison of the "standardized" bathymetry of the Southern

New England and New York transects reveals the following:

Table I.-Bathymetric differences between Southern New England and New

York. (Also, see Fig. 2.)

Southern Southern

Depth ranges New England New York New England New York

(m) nmi % nmi % ll% ll%

0-10 3 3.9 3 3.0 + .9

10-20 3 3.9 3 3.0 + .9

20-30 5 6.5 20 20.2 +13.7

30-40 18 23.4 21 21.2 + 2.2

40-50 3 3.8 11 11.1 + 7.3

50-60 15 19.5 6 6.1 +13.4

60-70 8 10.4 II 11.1 + .7

70-80 8 10.4 15 15.2 + 4.8

80-90 6 7.8 3 3.0 + 4.8

90-100 4 5.2 2 2.0 + 3.2

100-110 2 2.6 1 1.0 + 1.6

110-120 2 2.6 3 3.0 + .4

Totals n 100.0 99 99.9 27.0 26.9

1) The New York shelf break (120 m) is 43 km (23 nmi) farther

seaward than is the break off Southern New England, yielding

a 12% wider shelf.

2) Calculation of the distance across the bollom of the depth

ranges, taken at 10 m intervals from the beach to the shelf

break (120 m), shows significant differences between the two

transects (Table 1 and Fig. 2). For example, between the depth

• ranges of 0-10 m and 10-20 m there is < 1% difference between New York and Southern New England. However, in the

depth range of 20-30 m, there is almost 14% more bollom off

New York than Southern New England. For the depth ranges

pertinent to the Cold Pool (40-110 m), the differences between

New York and Southern New England are predictable. Both

occupy about the same distance across the bollom: 91 km (49

METHODS

o SO. NEW ENGLAND

g NEW YORK

I

0-10 10-20 20-)0

10

30 ....-,--,--,--,..---,--,--,--,--,--,---,r--,

20

20

40

0<

W

w 60

:E so. NEW ENGlANO"""

:r: 80

0 100

120

140

nmi) for New York compared with 85 km (46 nmi) for

Southern New England. However, the bottom distance along

the Southern New England transect, between the 40 and 110 m

isobaths, represents about 10% more of the shelf width than

does the similar distance along the New York transect. This is

reflected off Southern New England as a slight shift to seaward

into deeper (~ 10 m) water of the approximate center of the

cold pool.

3) The cross-sectional area of the water column from the beach

out to 120 m depth along the New York transect is 8.91 km2

and for the Southern New England transect 7.47 km2 ; however,

for the 40-1 10m depth ranges pertinent to the cold pool, the

cross-sectional areas were 2.34 km2 and 2.41 km2 , respectively.

Figure 2.-Plot of standard bathymetry along the Southern New England and

New York transects. The bar graph indicates percentage of bottom covered at 10

m intervals from 0 out to 120 m.

o

W

0<

W

>

o

u

74' 73' 72' 71 ' 70'

40'

41'

38'

39'

Figure I.-Locator chart showing transect envelopes for Southern New England

and New York. Shading indicates general area of cold pool occupation.

Almost 3,000 expendable bathythermographs (XBT's) were

dropped and over 200 transects collected along two routes (Fig. 1)

monitored by the NMFS/AEG (Atlantic Environmental Group)

2
Ships of Opportunity (SOOP) - Ocean Monitoring Program during

1977-81 (Table 2). These two .wutes (Southern New England and

New York) provide the basis of a unique set of subsurface

temperature and sea surface salinity data. Analysis of the more

than 200 vertical temperature sections collected during 1977-81

pointed out a need to summarize the data in a bottom t~mperature

vs. time form that would more conveniently describe average conditions.

A detailed description of the construction of bottom temperature plots on a time-depth field can be found in Chamberlin

(1978). Briefly, the plots are constructed from contoured vertical

temperature sections plotted from XBT data collected by our

SOOP - Ocean Monitoring Program. The points (depth) where the

whole degree isotherms intersect the bottom are plotted on a depth

vs. time grid bounded by depths of 0-200 m and time 0-360 Julian

Days. For the shallower depths, from the shore out to the first

XBT observation (usually about 30 m), we use temperature

recorder (deployed at 20 m off Southern New England) data

averaged and plotted by 10 Julian Day intervals and National

Ocean Survey (NOS) coastal tide station data (0 m) averaged by

month and plotted mid-month. The finished bottom temperature

plot, consisting of the combination of XBT, temperature recorder,

and NOS data, is then digitized at 10 m intervals, and interpolated

temperature values at 10 Julian Day intervals are calculated to

create the matrix that is contoured to produce bottom temperature

plots (Appendix Figs. 1-10) and composite or averaged plots

(Figs. 3,4).

Additional detail concerning bottom temperatures outside the

cold pool and water column characteristics for the years 1977-81

can be obtained from the annual reports in Annates Biologiques,

Volumes 34-38, for Southern New England (Crist and Chamber-·

lin 1979, 1980, 1981, 1983; Crist in press) and for New York

(Cook 1979; Cook and Hughes 1980; Hughes and Cook 1981,

1983, in press).

RESULTS

The cold pool, defined here as temperatures of 10°C or less on

the bottom temperature-depth vs. time plots, shows some similarities and major differences in the 5-yr averages for Southern New

England and New York (Figs. 3, 4).

Cold pool water attains its minimum temperature near shore

because of atmospheric winter cooling about Julian Day 30 (end

of January) on both the Southern New England « 10c) and the

Ne\\' York « 20c) transects. At the center of the feature, (about

70 m depth on the Southern New England transect and 60 m on

the New York) minimum temperatures of < 3°C are reached

about Julian Day 40 for Southern New England and < 5°C about

Julian Day 60 for New York.

The cold pool feature lasts until fall overturn which occurs

about 10 d earlier along the Southern New England transect than

off New York (Julian Day 265 vs. 275). It is at this time, when fall

overturn is complete, that the area on the bottom previously occupied by the cold pool reaches maximum temperature (> 14°C on

the Southern New England transect and> \2°C on the New York

transect). It should be noted that we have observed fall overturn

"maximum", on occasion, of more than \7°C on the New York

transect.

The average maximum seaward extension of the cold pool is

much less off Southern New England (130 m isobath) than off

New York (175 m isobath). Maximum seaward expansion occurs

about 20 d later off Southern New England than it does off New

York (Julian Day 80 vs. 60).

The most obvious difference between the Southern New

England and New York 5-yr average bottom temperature plots is

in the variability of the cold pool temperature gradients with time.

On the New York transect, periods of general warming in the cold

pool are interrupted by shorter periods of cooling. These interruptions in seasonal warming are much less in evidence off Southern

New England (see also Appendix Figs. 1 through 10). The cooling

events are so prevalent off New York that they cannot be averaged

out of the data set and even show up in the 5-yr average bottom

temperature plot (Fig. 4). As stated by Houghton et al. (1982),

these cooling interruptions on the New York transect are indicative of advective processes ongoing within the cold pool,

where cooler water from the Southern New England transect area

is transported southwestward into the New York transect area.

Table 2.-Annual distribution of XBT's collected on the Southern New England and New

York transects.

Southern

New England New York

1977 t978 t979 1960 1981 197'1 1978 1979 1980 1981

Jan X X X X X X X X X

Feb. X X X X X X

M'L X X X X X X X X X X

Apr. X X X X X X X X X

May X X X X X X X X X

June X X X X X X X X X X

July X X X X X X X X X

Aug. X X X X X X X X X X

Sept. X X X X X X X X X X

Oct. X X X X X X X X X X

Nov. X X X X X X X X

Dec. X X X X X X X X X X

Total no.

of transects 20 21 22 15 19 13 19 28 14 22

Total no.

of XBT's 172 239 275 193 195 142 291 452 379 592

Average/year 19 Transects 21 Transects

214 XBT's 371 XBT's

3
JULIAN DAYS

o 50 100 150 200 250 300 350

50

V)

a::

W

W

100

I

0-

Q

W

150 ~' 12

11

200

Figure 3.-Plot of average bottom temperature (0C) on depth-time grid for 1977-81 along the Southern New England transect. Shaded area is water of looe or less (cold

pool).

JULIAN DAYS

o 50 100 150 200 250 300 350

50

V)

a::

W

W

100

I

0-

W

0 150 o

Figure 4.-Plot of average bottom temperature (0C) on depth-time grid for 1977-81 along the New lon' transect. Shaded area is water of looe or less (cold pool).

4
Due to the closer proximity of the shelf/slope front to the 100 m

isobath on the Southern New England transect and the higher

occurrence of Gulf Stream warm core rings (Mizenko and

Chamberlin 1979) impinging on the shelf break off Southern New

England than off New York, one should expect to observe more

"calving" incidents. Several temperature sections drawn from

data collected off Southern New England and New York do show

parcels of cold pool water at depths of 50 m and more apparently

being drawn off the shelf iBto slope water. At other times, the cold

pool has appeared as two cells which could be interpreted as being

in two separate pieces or as a lobe of cold pool water such as

might occur along a meander that was transected obliquely. In

most of these "calving" instances, warm core Gulf Stream rings

were present along the transect.

Another technique for portraying the extent and temperature of

the cold pool was to calcuiate from the bottom temperature plots

(Figs. 3,4, and Appendix Figs. 1-5 and 8-12) the percentage of

"area" covered by water of IO D C or less and the weighted mean

temperature of the same pared of water. In other words, 100%

would equal the "area" (actually depth-time area) bounded by the

depth range 0 to 200 m and time bounded by Julian Day 0 to 360.

It is apparent from these calculations (Table 3) that there is 3.5%

more "area" covered by lOoC or less water along the New York

transect than there is along the Southern New England transect,

and the New York transect averages about 0.7°C warmer than

does the Southern New England transect.

Table 3.-Weighted mean temperature and percent of depth·time "area"

covered by water of < 10°C. ----

Southern New England New York

Weigh led Weighted

mean mean

temp. temp.

Years Source (0C) % Area Source (0C) % Area

1977 App. Fig. 1 6.7 26.0 App. Fig. 6 7.4 27.9

1978 App. Fig. 2 6.8 26.7 App. Fig. 7 7.5 30.3

1979 App. Fig. 3 6.6 22.1 App. Fig. 8 7.6 26.9

1980 App. Fig. 4 6.3 20.8 App. Fig. 9 7.6 27.2

1981 App. Fig. 5 6.5 20 I App. Fig. 10 7.6 26.2

1977·81 Fig. 3 6.8 22.6 Fig. 4 7.'; 26. '

Weighted mean bottom temperatures were calculated by

measuring the relative areas of water bounded by whole degree

isotherms (l 0, 2°, 3°, ... , 10°C) and using these area fractions as

weighting terms in computing the mean temperatures (Table 3).

This technique provides a single number for annual comparisons

and is proportional to the heat content of the cold pool; and should

show better than maximum or minimum temperatures the influence of a warm winter or cold winter on cold pool formation. If,

for instance, the winter was very cold and long lasting, one would

expect either lower bottom temperatures lasting longer, or usual

bottom temperatures occupying a larger "area", or both. If the

winter was unusually \\<arm, then one would expect either warmer

bottom temperatures or normally cool bottom temperatures

occupying a smaller "area". The weighted mean temperature will

reflect either condition.

The weighted mean temperatures (Table 3) show significant

annual cons:stency. The maximum variation of weighted mean

temperature off Southern New England was 0.5°C (:::: 8%) and

0.2 ° (:::: 3%) off New York. The only factors that would significantly influeace a weighted cold pool temperature would be the

intensiveness or mildness of winter and the timing of fall overturn.

5

Overturn occurring either early or late would decrease or increase

the overall duration of the cold pool. An unusually intense summer would not impact on the bottom signature of the cold pool,

because the bottom is essentially sealed off from the surface by

the thermocline until the fall overturn occurs. Increasing solar

radiation at the surface would only serve to warm the surface mixed layer. However, other sources of heating to the cold pool as

suggested by Ou and Houghton (1982) in the region of the Hudson

Shelf Valley could be explained by the alongshelf variation of the

heating rate. Other sources of heating can be attributed to slope

water intrusions up the Hudson Canyon and eventually into the

Hudson Shelf Valley.

Maximum and minimum average bottom temperatures for the

5-yr period at three depths (20 m-shoreward of the cold pool,

120 m-seaward of the cold pool, and 60 m-center of the cold

pool) were compared for both Southern New England and New

York transects.

Bottom temperatures at 20 m depths off Southern New England

show a minimum (0°-3°C) occurring on Julian Day 50, while off

New York the minimum (I 0-2.5°C) occurred on Julian Day 60.

Maximum temperatures (16°-18°C) off southern New England

occurred on Julian Day 255, while off New York maximum

temperatures (l3°-18°C) occurred on Julian Day 260. Both

transects, Southern New England and New York, are quite similar

for waters inshore of the cold pool. For waters offshore of the cold

pool (~ 120 m), a similar pattern of temperature and timing occurs, only with a smaller overall range in temperature. This is to

be expected, because the deeper or further offshore the less

measurable the surface influence becomes.

However, an interesting difference occurs within the cold pool

at 60 m depth (Fig. 5). Bottom temperatures plotted at 60 m off

Southern New England show minimum temperatures (1°-3°C)

occurring about Julian Day 66 (end of February) while off New

York minimum temperatures (4°·5°C) occur about Julian Day

160 (mid-June). Maximum temperatures (l3 0-l7 0C) off

Southern New England occur about Julian Day 312, while off

New York, maximum temperatures (IJO-14°C) occur about

Julian Day 332 (Table 4).

From these plots (Fig. 5), it is apparent that timing of maximum

cold pool temperatures between Southern New England and New

York is controlled by the timing of fall overturn. Timing of minimum temperature on the two transects is controlled by several

mechanisms, such as the timing and intensity of vernal warming,

speed, volume, and temperature of advected water, and crossfrontal processes ongoing between Southern New England and

New York (discussed earlier).

In the early part of the year (during minimum temperature for·

mation), the ranges in temperature off Southern New England and

New York do not overlap (Fig. 5), as they do for most of the rest of

the year. The bottom water temperatures off Southern New

England have the largest range, that is to say that Southern New

England is both colder in the winter and hotter at fall overturn

than New York. New York minimum temperatures, although not

as cold as Southern New England, occur about 100 dafter

Southern New England-again indicative of advection of cooler

water within the cold pool from Southern New England to New

York.

NUMERICAL ANALYSIS

Several simple equations were developed in an effort to more

easily describe the cold pool temperature cycles. Average bottom

temperatures from 60 m depth taken from the 1977-81 bottom
D

D

Figure 5.-Plot of maximum and minImum observed bottom

temperature (0C) at 60 m depth (approximate core of tbe cold pool)

for Southern New England transect (top), New York transect

(middle), and composite of both transects (bottom). Based on

1977-81 data.

D

Southern New England-warming (decad units 10-250)

Southern New England-cooling (decad/pentad units 260-365)

Due to the cooling lag that occurs off New York, the warming

period is shortened to decads 110-250; and a quadratic equation

was developed for the decads 10-100.

The correlation coefficient (R2) measures how much variation

in the dependent parameter can be accounted for by equation.

Both Southern New England and New York indicate a strong

linear association between average temperature and Julian Days.

Sample size (N) is also shown for all equations.

R2 = 0.98

N = 15

R2 = 0.99

N = 11

R2 = 0.96

N = 25

A = 0.350 + 0.043 (T)

(0.293) (0.002)

A = 43.123 - 0.113 (T)

(1.330) (0.004)

A = 1.875 + 0.043 (T)

(0.260) (0.002)

New York-warming (decad units 110-250)

temperature plots (Figs. 3, 4) were used in the model development.

Linear regression equations relating A (average temperature

1977-81 at 60 m depth) to T (time-decad/pentad units 10-365)

were developed for Southern New England and New York. In an

effort to more accurately reflect the data via the regressions, we

chose to break the year into seasonal warming (decads 10-250,

Julian Day 70-310) and seasonal cooling (decads/pentads

260-365, Julian Day 320·60) periods. The use of neutral

decad/pentad units (a common meteorological technique) was

used to provide for an always increasing X-axis number in order

to make the calculating of the simple statistics easier. The actual

Julian Day counterpart and approximate month for the decad/

pentad units are shown in Table 5.

The standard errors of coefficients are shown in parentheses for

all equations. The standard errors for all equations were smaller

than the slopes of the independent parameter (T) suggesting that

the influence exerted by T has meaningful effect on the dependent

parameter A.

A more acurate test of an independent parameter's significance

is the Student t statistic, which was highly significant with P >

0.0001 for all equations. Another measure of how well the equation, as a whole, accounts for the dependent parameter's behavior

is the F statistic, which was also highly significant for all equations with a P > 0.0001 (F statistic).

Table 4.-Derived maximum, minimum, and average of bottom temperatures at 60 m depth

(mid-point of the cold pool) and their timing in Julian Days. Collected for 5 yr (1977-81) for the

Southern New England and New York transects.

Southern New England New York

Min. Timing Max. Timing Min. Timing Max. Timing

Years temp.oC J. Day temp. °C J. Day temp. °C J. Day temp.oC J. Day

1977 1.3 60 17.0 310 3.8 150 14.1 330

1978 2.0 70 13.8 320 3.8 150 14.1 340

1979 1.9 60 14.9 330 3.8 160 12.6 350

1980 2.8 60 17.2 290 4.6 160 13.3 320

1981 3.3 80 12.7 310 4.9 160 11.4 320

Avg. 2.3 66 15.1 312 4.2 156 13.1 332

6
Previously published information, in conjunction with the 5-yr

time series presented here, leads to the following conclusions in

describing the cold pool feature.

1) The cold pool is formed every year with the onset of vernal

warming and persists until fall overturn. As summer progresses

and the thermocline intensifies, the cold pool is sealed off from

surface influence and becomes more identifiable as a thermal

Table 5.-Comparison of Julian Day and decad/

pentad units and approximate months for both

warming and cooling periods. Decad/pentad units

are used in calculating average temperatures from

the equations used in the numerical analysis of the

cold pool.

Decad/

Julian Pentad Approximate

Day units months

70 10

80 20 March

90 30

100 40

110 50 April

120 60

130 70

140 80 May

150 90

160 100

Warming 170 110 June

180 120 period

190 130

200 140 July

210 150

220 160

230 170 August

240 180

250 190

260 200 September

270 210

280 220

290 230 October

300 240

310 250

320 260 November

330 270

340 280

Cooling 350 290 December

360 300 period

10 315

20 325 January

30 335

40 345

50 355 February

60 365

New York-cooling (decad/pentad units 260-365)

A = 31.543 - 0.069 (T)

(1.442) (0.005)

New York-cooling lag (decad units 10-100)

A = 4.377 + 0.058 (T) - 0.0006 (Tl)

(0.223) (0.009) (0.00008)

CONCLUSIONS

R2 = 0.96

N = II

R2 = 0.91

N = 10

7

barrier. The timing of formation and destruction is consistent

(±10 Julian Days) year to year.

2) The cold pool is a mostly continuous feature extending from

the northeast point of Georges Bank (Gulf of Maine?) to the

area between Chesapeake Bay and Cape Hatteras, where it is

mixed away along with the slope water by interaction with the

Gulf Stream. Along its course, the cold pool can vary in width

across the bottom and thickness on the bottom but generally is

located between 40 and 110m depth, and represents about

28% of the total volume of shelf water within the Middle

Atlantic Bight.

3) The cold pool is made up of winter-cooled mixed shelf and

slope water, with an additional advective source from. the Gulf

of Maine.

4) The cold pool is consistent year to year in both "area"

(occupying about 24% of the area on the depth vs. time plot)

and weighted mean temperature (averaging a little more than

7°C).

5) The water within the cold pool flows from the northeast to the

southwest at rates of 1-3 cm/s (0.5 to 1.4 nmi/d).

6) Several processes (wind, rings, ... etc.) can influence the position, shape, and intensity of the cold pool. These processes can

manifest themselves as cold pool meandering, calving, lobes,

lenses, and high or low cross-frontal mixing rates.

7) The major differences in the cold pool off New York from that

off Southern New England are the 100-d lag in the occurrence

of minimum temperature along the New York transect from

that of the Southern New England, and that the Southern New

England transect is always cooler in the winter and warmer at

fall overturn than the New York transect.

8) The cold pool along both transects can be described with a

relatively simple numerical analysis, with the New York

transect. due to its cooling lag, necessitating a more complex

model.

ACKNOWLEDGMENTS

Appreciation is extended to several people associated with the

collection, quality control, processing, and portrayal of these large

and disparate data sets: R. W. Crist, J. L. Chamberlin, R. L. Benway, S. Lundin, G. White, J. Jossi, G. Wood, M. M. Hughes, L.

Armstrong, and a special thanks to S. Matteson for the model

development.

LITERATURE CITED

BEARDSLEY. R. c., w. C. BOICOURT. and D. V. HANSEN.

1976. Physical oceanography of the Middle Atlantic Bight. In M. G. Gross

(editor), Middle Atlantic Continental Shelf and the New York Bight, Vol. 2,

p. 20-34. Am. Soc. Limnol. Oceanogl'., Lawrence, Kansas.

BIGELOW, H. B.

1933. Studies of the waters on the continental shelf, Cape Cod to Chesapeake

Bay, I. The cycle of temperature. Pap. Phys. Oceanogr. Meteorol., Mass.

Inst. Technol. and Woods Hole Oceanogr. Inst. 2(4), 135 p.

CHAMBERLIN. J. L.

1978. Temperature structure on the continental shelf and slope south of New

England during 1975. In J. R. Goulet, Jr. and E. D. Haynes (editors), Ocean

variability: Effects on U.S. marine fishery resources - 1975, p. 271-292.

U.S. Dep. Commer., NOAA Tech. Rep. NMFS Circ. 416.

COLTON, 1. B., Jr., R. R. MARAK, S. R. NICKERSON, and P. R. STODDARD.

1968. Physical, chemical, and biological observations on the continental

shelf, Nova Scotia to Long Island, 1964-66. U.S. Fish Wildl. Serv., Data

Rep. 23, 189 p.

COOK, S. K.

1979. Water column thermal structure across the shelf and slope southeast of

Sandy Hook, New Jersey, USA, in 1977. Ann. BioI. 34:14-21.
COOK, S. K., and C. E. GARDNER.

1978. An example of rapid change in the summertime water column overthe

continental shelf southeast of Sandy Hook, N.J. Gulfstream IV(5):6-7.

COOK, S. K., and M. M. HUGHES.

1980. Water column thermal structure across the shelf and slope southeast of

Sandy Hook, N.J., USA, in 1978. Ann. BioI. 35:14-25.

CRIST, R. W.

In press. Bottom temperatures on the continental shelf and slope south of New

England in 1981. Ann. BioI.

CRIST, R. W., and J. L. CHAMBERLIN.

1979. Bottom temperatures on the continental shelf and slope south of New

England in 1977. Ann. BioI. 34:21-27.

1980. Bottom temperatures on the continental shelf and slope south of New

England in 1978. Ann. BioI. 35:25-30.

1981. Bottom temperatures on the continental shelf and slope south of New

England in 1979. Ann. BioI. 36:25-28.

1983. Bottom temperatures on the continental shelf and slope south of New

England in 1980. Ann. BioI. 37:18-20.

CSANADY, G. T.

1978. Wind effects on surface to bottom fronts. J. Geophys. Res. 83(C9):

4633-4640.

FISHER, A., Jr.

1972. Entrainment of shelf water by the Gulf Stream northeast of Cape

Hatteras. J. Geophys. Res. 77:3248-3255.

FORD, W. L., J. R. LONGARD, and R. E. BANKS.

1952. On the nature, occurrence and origin of cold low salinity water along

the edge of the Gulf Stream. J. Mar. Res. 11:281-293.

HAN, G., and T. NIEDRAUER.

198 I. Hydrographic observations and mixing processes in the New York

Bight,1975-1977. Limnol. Oceanogr. 26:1126-1141.

HICKS, D. C., and J. R. MILLER.

1980. Meteorological forcing and bottom water movement off the northern

New Jersey coast. Estuarine Coastal Mar. Sci. 11:563-571.

HOPKINS, T. S., and N. GARFIELD III.

1979. Gulf of Maine intermediate water. J. Mar. Res. 37(1):103-139.

HOUGHTON, R. W., R. SCHLITZ, R. C. BEARDSLEY, B. BUTMAN, and J. L.

CHAMBERLIN.

1982. The Middle Atlantic Bight cold pool: Evolution of the temperature

structure during summer 1979. 1. Phys. Oceanogr. 12:1019-1029.

HUGHES, M. M., and S. K. COOK.

1981. Water column thermal structure across the shelf and slope southeast of

Sandy Hook, New Jersey, in 1979. Ann. BioI. 36:15-25.

1983. Water column thermal structure across the shelf and slope southeast of

Sandy Hook, New Jersey, in 1980. Ann. BioI. 37:14-18.

In press. Water column thermal structure across the shelf and slope southeast

of Sandy Hook, New Jersey, in 1981. Ann. BioI.

KETCHUM, B. H., and N. CORWIN.

1964. The persistence of "winter" water on the continental shelf south of

Long Island, New York. Limnol. Oceanogr. 9:467-475.

KUPFERMAN, S. L., and N. GARFIELD.

1977. Transport of low-salinity water at the slope water-Gulf Stream boundary. J. Geophys. Res. 82:3481-3486.

LIMEBURNER, J. A., J. VERMERSCH, and R. BEARDSLEY.

1978. Hydrographic station data obtained in the vicinity of Georges Bank,

May and August, 1976. Woods Hole Oceanogr. Inst. Tech. Rep. 78-82, p.

1-116.

MAYER, D. A., D. V. HANSEN, and D. O. ORTMAN.

1979. Long-term current and temperature observations on the Middle Atlantic Shelf. 1. Geophys. Res. 84:1776-1792.

MIZENKO, D., and 1. L. CHAMBERLIN.

1979. Anticyclonic Gulf Stream eddies off the northeastern United States

during 1976./n J. R. Goulet, Jr. and E. D. Haynes (editors), Ocean variability

in the U.S. Fishery Conservation Zone, 1976, p. 259-280. U.S. Dep.

Commer., NOAA Tech. Rep. NMFS Circ. 427.

MOOERS, C. N. K., R. W. GARVINE, and W. W. MARTIN.

1979. Summertime synoptic variability of the Middle Atlantic Shelf water!

slope water front. J. Geophys. Res. 84(C8):4837-4854.

OU, H. W., and R. HOUGHTON.

1982. A model of the summer progression of the cold-pool temperature in the

Middle Atlantic Bight. J. Phys. Oceanogr. 12:1030-1036.

WHITCOMB, V. L.

1970. Oceanography of the mid-Atlantic Bight in support ofICNAF, September-December 1967. U.S. Coast Guard Oceanogr. Rep. 35,157 p.

WRIGHT, W. R.

1976. The limits of shelf water south of Cape Cod, 1941 to 1972. J. Mar.

Res. 34:1-14.

APPENDIX FIGURES

Bottom temperature plots for both the Southern New England and New York transects are

presented for each year used in this time series study. Cold pool water (10oC or less) has been

shaded for easier comparison with the averaged plots. The bracketed lines at the bottom of each

plot represent those times and duratioo when rings were present along the transects.

8
JULIAN DAYS

o 50 100 150 200 250 300 350

I • I

NEW ENGLAND

I I

1977 SO.

H

(O( )

H

BOTTOM TEMPERATURE

I I

o l .. i (:,\. \ .\' ...... '.".!"..\:;:"{~",>, _ { \ \: \: \: '.::::::<.:::<oc:::::::::! I ! ::> I I I I ! ! .. u

7 I I I I I I I!'!!!!~ j I.'. .\ . .j. .. '1' \ '

200 ,(iiirIi... 1 ! Iii I , I Iii 1\ I iii iii \ ) / IiiI' ',\, ,C, 4' i I I I I I

50

-

l/)

UJ

.-

UJ

"'--~~

\0 l/ ,) . /\0.-

\ ()\iv/

Appendix Figure I.-Plot of bottom temperature (0C) on depth·time grid along the Southern New England transect for 1977.
o 50 100

JULIAN

150

DAYS

200 250 300 350

o ...! ••• \ •• ""'!4i,l. 'F \ r't I' [ t_\ '\ \' (', \: <:: < <: <:: ol:::::::::! C:::::::=>')' i " I I' 1'1 I I! \ I \!, l_t~{ ..!x ••

50

---

V>

O!

W

IW

:E 100

:; I

IQ...

W

0 150

200' i I \ Iii I " Iii i , ,....-:=;> ii' i i \ I, I , , iii i it)I / I \ i! I ) i , ,

BOTTOM TEMPERATURE (O() 1978 SO. NEW ENGLAND

Appendix Figure 2.-Plot of bottom temperature (0C) on depth·time grid along the Southern New England transect for 1978.
JULIAN DAYS

o 50 100 150 200 250 300 350

'-

......

/

......

......

...... ......

;-

12

o t .. C! •• i!. __ ~_{_I ••• \ __ \ .. _~_ ..\~.X.1 i_it \ < ( '( <' <', t " Ie '<:' ! ! :> !, 'i " " \', \ " i' " \ '( 't <l\ ,

200' " i , iii Iii i i 'i ii'ii" ) ii, i "i , , iii \, " i i if i r ,

50

-

V>

cz:

W

IW

100

-- I

Ia...

w In'l ("'\. , \ ( I \. 12

0 150J 12 I \ I 1

12

I I I I I I

BOTTOM TEMPERATURE (Ge) 1979 so. NEW ENGLAND

Appendix Figure 3.-Plot of bottom temperature (OCl on depth-time grid along the Southern New England transect for 1979.
JULIAN DAYS

a 50 100 150 200 250 300 350

--i I I I I I I I I I I I I I I I 1:7 I I , I I I I I h-1 0 ..\ \ : \ ..\ ~.\..~. \ \ \ \ \ '__ \ u 7 I \ \ \ \ \\\.\.. (.::'\:' 1\ .

200' i 'i> i \ i 'i i l i II' J t i j i' I j I I « iii i I Ii' i r iii i ,

50

l/)

W

l- I "","-;....~~;/~_ \~~,/.",.r. . . •... ;o .../ .. ......... ::: ::f / --...... J \ "-./ 1£ \ \ \ \. ------=:..-

w

100

I ' .. \

" ........ \ \: 'i.. :-;r././ / ../' \ \ ,..../ /

tv I

fI \),~ 1\0 UL '----/

I0- n 'D 12

w

0 150

12

BOTTOM TEMPERATURE (Oe) 1980 SO. NEW ENGLAND

Appendix Figure 4.-Plot of bottom temperature (0C) on depth.time grid along the Southern New England transect for 1980.
JULIAN DAYS

50 100 150 200 250 300 350

o ... I... ![ __ I__ .!lt.t.. !...I1.\.L:::G.I.K:!U:~ .( \~ .. I(\\~l~l I I I) I ) 11i))1 I I ! 7I I \\\\l".L.'.,.. j,,~

200' Iii Iii ii' I I Iii I I I I i II I I I II r \ i (' i '1 i ! I 'I \ ,

50

---

V>

ill

..-

ill

100

;::;

I +J3

I \ ":....:y I I I I / "----/ J / If I 12

..-

a.... I 12

ill

0 150

I I I I

BOTTOM TEMPERATURE (O() 1981 SO. NEW ENGLAND

Appendix Figure S.-Plot of bottom temperature (0C) on depth-time grid along the Southern New England transect for 1981.
JU LIAN DAYS

o 50 100 150 200 250 300 350

I I I I I I I I I , I I I t I J J.. I I I I::;J I I I I I I I I I I I 021 ........ x. .. . _ ( < \ i , '''' i \ \ \ \ ( \ (\: \\\~ 7 I I I \ \ i ( ( (i \ , \ i

200' i I I i I I (i )I Iii " i \ iii iii I I I I I' ,I' I Ii i I I 'I I i ( iii'

-(/')

0::

W

IW

100

- --I:> I

Ia..

w

0

150

MAXIMUM BOTTOM TEMPERATURE (Oe) 1977 -1981 SO. NEW ENGLAND

Appendix Figure 6.-Plot oC maximum bottom temperature (0C) on depth-time grid Cor 1977-81 along the Southern New England transect.
o 50 100

JU LI AN

150

DAYS

200 250 300 350

o lo::!:: __ I::::::J . \ <I I I I I I < \ \ <_ ,- ! o::!: I I cc::::::: \ < \ \ < 'C al: i.e:::: 'xc:::::!:: ! __ J ;;>1 I I I I I I i 1 i I I !i \ < Ci_Ct.'C ! ! .....

! ! l ...1 \J..-

50

-

V')

Ol::

W

.....

w

:E 100 - -

Vt I

......

a...

w

0

150

200 ,.. olo.Oj •• oio··l Ir' I, i i Y I Iii i i > i II i i \ iii i I, i" (' i 1> ~l -,

MINIMUM BOTTOM TEMPERATURE (OC) 1977 - 1981 SO. NEW ENGLAN D

Appendix Figure 7.-Plot of minimum bottom temperature (0C) on depth-time grid for 1977-81 along the Southern New England transect.
JU LI AN DAYS

50 100 150 200 250 300 350

50 ...-

V>

UJ

IUJ

100

- 0\

I

I0-

UJ

0 150

J ~1 I I \

12 I I I I

200 -Y (

10 \J

Q

\ / / \ \

BOTTOM TEMPERATURE (O() 1977 NEW YORK

Appendix Figure S.-Plot of bottom temperature (0C) on depth-time grid along the New York transect for 1977.
JULIAN DAYS

o 50 100 150 200 250 300 350

TEM PER AT URE (0 C) 1978 NEW

o k. 't! _x.! __ c _. .' . . j '... 1.... \ .. , .. 1. '••(. !(.. "..<. »c I '« '<: < '<:: ! <::: <:: '«! < 'cc:::::: ! <::::: ':c::::::::.:.:-! >' j I Ii)I I '< \ '\,'. s::. !c ..l .. '... J

200' ( i i \ i { , «I ,I''>. Ii"""'" I I r . 0, ... i .. ", ... ,0 .... 1 i " " I i I \ iii \ (I i "'I Ii'

50

--

V>

CY:

ill

Iill

100-

:::;

::r:

ln....

ill

0 150

Appendix Figure 9.-Plot of bottom temperature (0C) on depth-time grid along the New York transect for 1978.
JULIAN DAYS

o 50 100 150 200 250 300 350

a ~,.JJ ..l .. ...'.i__ I_\. '< ,'\j".!.... ~.c:::.IC<!:ee::::: \: " (' <'< l:::<:::cL::_'_>' I , I<! i \ ,Ii I' " ) I) t ....!.( __ I~_~,«<J

{ !" ( " , 200' j iii "" ill .' i i Ii i , I , I' 'i' i ) iii iii I I I i I

50

-

V")

W

tw

100f '\,\>\11/1 ;x;

13 :;::::::::;:::;: ...... ::;:::::p

12 : : :: ;: . : : : ;: :: . : : : • • 12 I ............. t- / ...........

........... Cl- ......... .

w

o 150

BOTTOM TEMPERATURE (Oe) 1979 NEW YORK

Appendix Figure IO.-Plot of bottom temperature (Gel on depth.time grid along the New York transect for 1979.
JULIAN DAYS

350

(1-//

o 50 100 150 200 250 300

0''''.:,''·'\···0 --i I I I ...... I I I '(.. c::::::.~. 'o::::.\(. I \ ~~OC::::::::" I I I \ ~I .J:::: I I I I I } I I I I 1\ I \ \ \ I I I I e:_'\ __\__I,-_0:\:~ t200r 1'1" 1 jl.r'j"'{'j i'i i l'i'I'¥"j 1'\ , t' i i'i'i i 1'1 I'l j / i'

50

V>

w

Iw

100~\J I~' \~\\~\T0~jln r·V.. ··~····~/ / \ ~~7 / / I .. ..... ..... ........ ... ...... \ \ ::::: ~::~::: ::T'lO':::' .:::::::.

\ \

I \'-

\0 3'1 \\\\\oV.7Y! ~/ \ I

I .............

.............. \ l- e •••••••• " •

............ \ a.... ............ 12 ............

............ w , ........... ,---- I

o 150

13

BOTTOM TEMPE RATURE (O() 1980 NEW YORK

Appendix Figure n.-Plot of bottom temperature (0C) on deptb-time grid along the New York transect for 1980.
JULIAN DAYS

o 50 100 150 200 250 300 350

10

..........

12

13

12

(J

o I .J I (. \ • i J • •,!....... <..I te•. 's:::...l . j '. _ I ' i ! i It <' < '.. I <::cc:::::::::l: <: '::ac:::!:= ",' 11 -=> ! III il') I ( ! \ I \ I \' ( I < , < I • I

50

V)

Ck::

Ll.J

ILl.J

100-i " \

\ tv

\ 0

I

\ l- I

0- \ 12

Ll.J \

0 \ 150 \

I

11

J

/

- .-' l--

200

BOTTOM TEMPERATURE (Oe) 1981 NEW YORK

Appendix Figure 12.-Plot of bottom temperature (0C) on depth·time grid along the New York transect for 1981.
JULIAN DAYS

o 100 150 200 250 300 350

o I I I l I I I I I I I I I I I I I I I I I .. I.. [Ii .1",/ --1,.. ",",,,,,'' ,.... , " X \: 'I: \ \ \ t•• \ \ } I I I t \ \ \ \ \" '( _"\: .

200 I I (\ , I '" \ I I l I I I r I I I I I I I I I I I I I I I I I I I I I I r I I

50

-

V')

W

....-

W

100 I I I I I , I I I J \••••• 1 '\. •• " , I I , '-'( N I 13

I\\~<>J~~ I J I 14 - ....-

a.... 0 Y l w 0

3

0

150 131 12 I' ,

12

/"... (

12

MAXIMUM BOTTOM TEMPERATURE (O() 1977 -1981 NEW YORK

Appendix Figure B.-Piot of maximum bottom temperature (0C) on depth·tlme grid for 1977·81 along the New York transect.
o 50 100

JULIAN

150

DAYS

200 250 300 350

50

-

V")

0:::

W

IW

100 - N I

l- N

n..

W

0

150

200 I! I J _. - y 1 . , 1\ \ r r" """ "1'" v \V{\~I I I I I I I I \ 1\ I i I I I I I I I I I I I I I I I I I I I I I r

MINIMUM BOTTOM TEMPERATURE (O() 1977 -1981 NEW YORK

Appendix Figure 14.-Plol of minimum bollom temperature (0C) on depth-time grid for 1977-81 along the New York transect.