by Christian Haas and Jan L. Lieser

Sea Ice conditions in theTranspolar Drift in AugustJSeptember 2001.

Observations during POLARSTERN cruise ARKTIS XVIIl2

Compiled by

Christian Haas and Jan L. Lieser

Ber. Polarforsch. Meeresforsch. 441 (2003)

ISSN 1618 - 3193

Contents

Foreward and Summary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . - 5

Introduction . . ^. . . . ^{. . .} . . . ^{. . .} . . . . ^{. .} . . . ^{. . . .} . . . ^{. .} . . . ^{. . . .} . 5

General ice conditions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7

Melt ponds . . . . ^{. . .} . . . ^{. .} . . . ^{. .} . . . ^. . ^. . ^{. .} . . . . ^{. . .} . ^. . . . ^{. . . .} . . . . ^{. .} . . . 8

Dirty ice and icebergs . . . . . . ^{. . .} . . . . ^{. . .} . . . ^{. .} . ^{. . .} . . . ^{. . . .} . . . 8

Data and images . . . . . . . . . . . . . . . . . . . . . ^{. . .} . . . . . . . . . . . . . . . . . . . . 10

A detailed description of the sea ice measurements and sampling during the expedition ARKTIS 17-2 can be found in Thiede (2002).

Data and color images are available via

http://www.awi-bremerhaven.de/Modelling/SEAICE/icereport/index.html

Foreword and Summary

This report summarises visual shipboard ice observations carried out during leg ARKTIS 1712 (ARK 1712) of RV POLARSTERN in August and September 2001, operating along the Gakkel Ridge and at the North Pole. Data on general ice conditions, navigational information as well as photographs taken from the ships bridge are presented. Although most data are subject to large uncertainties due to the different experience of observers, they provide a general and quite representative overview of recent summer conditions in the Transpolar Drift, as Seen from a ship. The data and photographs might be of interest as background information for discussions of recent changes of Arctic sea ice, and for comparisons with observations performed in other years. For those who have not Seen a sea ice landscape so far, this report might yield first impressions of what the Arctic sea ice cover looks like. For scientists working On remote sensing, modelling, or other aspects of sea ice, the report provides some ground-truth and boundary conditions for their work in the summer of 2001.

Ice conditions were characterised by very easily penetrable ice in the first half of the cruise, West of 3WE. There were many large leads with ice concentrations ranging between only 60% and 90%.

Only from late August onwards, and east of 3WE, narrower leads and ice concentrations above 90%

were observed. At that time, also new ice started to form on the leads. In the late period, sometimes the ship became beset in convergent ice conditions. Initially, melt ponds were observed to cover 10%

to 30% of the ice surface. The ponds were ice covered already when we entered the ice in early August. However, the pond ice cover was thick enough to step on (>0.05 m) only after about August 20. Melt ponds became Snow covered for some period, before they were visible again. Only after mid-September air temperatures permanently dropped below WC, and no Snow or surface melting was observed any more.

Introduction

ARK 1712 commenced on July 31, 2001, in TromsG, Norway, and ended October 7, 2001, in Bre-

merhaven. The ice was entered on August 4, and left only on September 28, i.e. after 56 days of ice

breaking. The mean ice concentration in August and September as retrieved from satellite passive-

microwave data (SSMII) and the cruise track are shown in Figure 1. The main focus of the cruise

was to investigate petrological and geological features and conditions of the Gakkel Ridge (Thiede

et al.,2002). In fact, ARK 1712 was part of the AMORE 2001 expedition (Arctic Mid Ocean Ridge

Expedition), and was performed jointly with the US Coast Guard Cutter HEALY. She is visible on

some Images, too. Thus, the ships mostly operated along the ridge between 6OW and 74'E. Only a

short seismic transect lead to the North Pole before returning to the Gakkel Ridge. Ice observations

are performed as part of a larger sea ice research program including physical, biological, and geolog-

ical ice core work as well as extensive thickness and morphology measurements. Visual observations

were performed on an hourly basis. However, due to other commitments of the team there were many

gaps in the record, and on average observations were performed only performed every 2.6 hours. Vari-

ables like ice concentration, ice thickness, floe and lead size, melt-pond coverage, ridge frequency,

as well as the occurrence of dirty ice and icebergs were recorded, representing ice conditions in an

area of 500 to 1000 m around the ship. In total, 51 1 observations were carried out. Note that these

observations could be highly biased by the partially poor visibility. Figure 2 shows more details of

the cruise track and the daily midnight positions.

0 Ice concentration, % 100

Figure 1: Cruise track of ARK 1712 and mean ice concentration during the cruise, in August and September 2001. Data were retrieved from satellite passive-microwave measurements (SSMII) pro- vided through EOSDIS NSIDC Distributed Active Archive Center, University of Colorado, Boulder.

Note the strong retreat of the ice in the Greenland Sea.

Figure 2: Map of the study regions with the cruise track and daily midnight ship-positions (circles).

Colours indicate mean September ice concentration (c.f. Figure 1).

- 6 -

General ice conditions

Figure 3a) shows the ice concentration versus longitude, roughly representing a profile along the Transpolar Drift. It can be Seen that the cruise track could be subdivided into two distinctiy different sections. West of about 4S0E, ice concentration was only between 60% and 90%. These, leads or polynjas with dimensions from 0 m up to 1000 m occurred between floes with typical diameters between 100 m to 2000 m (Figure 3b). These large polynjas are generated by divergent ice motion and are typical for summer conditions in the Central Arctic. Only east of 4S0E ice concentration increased to 90% and more. At the North Pole, ice concentration was 95%, with 2m thick floes of 300 m to 1000 m in diameter and narrow leads less than 50 m wide, covered with new ice. After September 13, when air temperatures decreased significantly below -S° for most of the expedition period, ice concentration was mostly close to 100%, because all leads were covered by nilas or grey ice. In the eastern region, most leads were 50 in to 100 m wide (Figure 3b). However, at many locations the leads were covered with small thick floes, such that ice breaking became more difficult.

20 40 60 80 100 120

Longitude, 'E

0 20 40 60 80 100 120

Longitude, 'E

Figure 3: Observations of ice concentration and lead width along the Transpolar Drift. The solid line

in a) is a 21 point running average.

Melt ponds

In Figure 4 a time series of melt pond coverage is shown. Melt ponds were well developed at the time when we entered the study region. The water surface of most ponds was at sea level, indicating that ponds were drained and in hydrostatic equilibrium with the underlying sea water. Typical pond depths ranged between 0.2 m and 0.4 m. It should be noted however, that most ponds were already covered by a thin ice sind when we entered the ice on August 4. Upon leaving the ice on September 28, the pond ice Cover had a thickness of 0.3 m to 0.4 m. The decreases in pond coverage around observations 50, 160, and 290 are due to recently fallen snow making the identification of frozen ponds impossible. Later On, the bigger frozen ponds became visible again because the floes were partially blown snow-free by strong winds.

0 50 100 150 200 250 300

Observation No.

Figure 4: Time series of melt pond coverage from the first until the last day in the ice. The solid line is a 9 point running average. Data are from visual observations of ice conditions.

Dirty ice and icebergs

Interestingly, dirty ice was almost only observed in the Western and southern study areas. Figure 6 shows the spatial distribution of icebergs. There were mainly two regions where icebergs were observed, partially in quite high numbers. Many icebergs had diameters of more than 100 m, and were sediment covered. Some big rocks were found on some of them, too. Some icebergs had a very rough pinnacled surface with melt ponds located in the troughs.

Reference

Thiede, J. and the Shipboard Scientific Party, 2002: POLARSTERN ARKTIS XVII/2 Cruise Report:

AMORE 2001 (Arctic Mid Ocean Ridge Expedition), Rep. on Polar and Marine Res. 42112002,

Alfred Wegener Institute for Polar and Marine Research, Bremerhaven, Germany.

Figure 5: Photographs of typical Icebergs in the Transpolar Drift

Figure 6: Spatial distribution of numbers of icebergs per observation.

- 9 -

20:W going through big lead, up to 200m width, poor visibility because of fog, no ice thickness estimates 21 :00 poor visibility

22:00 some fog, following HEALY

23:W photos taken after observation in more ice free area

Hour Port Ahead Starboard

Hour Port Ahead Starboard

14:OO

0:00 steaming in lead

15:00 dirty ice difficult to See because of snow Cover, melt ponds frozen over, dark and light blue 20:00 transiling from going in lead to ice

Hour Port Ahead Starboard

5.8.2001

Hour Port Ahead Starboard

12:00 low Stratus, p w r visibihty 16:00 fog

17:00 on station, poor visibitity 2!:00 clear visibility, fog ahead

Hour Port Ahcad Starboard

Hour Port Ahead S tarboard

-

C thin ice <3@m [%I

2.

^{N N N ? -----W}

-

L L ;A Typical sra icc thtckness [ml

2

Ã

,,

Ã

g g g g g

G Snow thickness [cml 5

2 3 2 E $ 3 E E E

Typical tioe dtametcr [m]

B E E E ³ E ^{3 3}

Max. iioc dtameter [m[

- - -

^{m N N a}

-

^N

-

^{W W W N}

-

^N Mclt pond coveragc

g

o o o o o o ' a m " , o o o o m o

$

^,d Typical ponddiameter[ml

3

- - - -

N w N - N Maximum pond diameter lml Diny icc concentration [%I

W

* 3

g

2

g g

g

g

g

~ e a d width lml

NW

0 0 N L a d fiocs. diametcr [ml

...---+

W L L L Typical ridge he~ght [ml

% 8

^W

^,,

^{W .V ",!-'}

^*

Max. cidgeheightlml

g

5

g

5

^g

^{2 2 Ã 2}

^{g $}

²

Typical ridge spacrng [ml

- ^{- - - -} -

Ridges: New=O,Old=I.Both=Z

d 0 U Rubble lields, coverage

[%I

*

,W

-

N N U ' 4 Iceberp, Number of

Hour

1200

Port

7.8.2001

Ahead Starboard

Hour Port Ahead Starboard

Data and color images ase available via

http://www.awi-bremeshaven.de/Modelling/SEAICE/icerepo~~~index.htmI

1O:W very poor vis,biljty <300n1 11:00 poor \,is~b~lity, no icc observations 14:00 follow~ng HEALY while streamering 15:W poorvis~b~lity

Hour Port Ahead Starboard

Hour

15:OO

Port Ahead Starboard

2 % ;

^W

-

2 g g

L Typical sea sce thickness Iml

a.

S, 3

^0

$

g

g g

;

5

;

g

Snow thickness [cml

E. -c

=- 00

- W - N U N N N N

>

8 8 8 8 8 8 8 8 8

Typiciil floediameter [ml

t^->

s = 0

$ 3 8

Max. floe d ~ a m a c r [ m l

0

lÑ

U

-

Mett pond coverage [%I

N W r n v n U W v n Typical pond diameter [m}

g 5 5 5 Maximum pond diameter [ml Dirty iceconcentration [%I

g - >, G

g Lcad width (ml

à 2 J

Typical ridgc spacing [ml

-

^W

- - .

Ridges: New=O,OId=l,Both=2

U U

Ã

Rubble fields. coverage 1961 lcebergs. Number of

9.8.2001

Hour Port Ahead

I 84.12 0.30 8.1 185 1.5 0 2 2 95 1.8 20 200 500 5 5 10 0 20 10 1 2 200 1 1 0 3 84.13 0.33 7.3 183 1.3 0 2 2 95 I 8 20 200 500 5 5 10 0 20 10 I 2 200 l I 0

I5 Um 0.48 6.3 119 1.4 5.3 3 3 95 1.5 15 100 200 2 0 20 5 2 100 1 15

17 83.97 0.68 6.3 125 0.9 90 2 10 500 100 5 5 20 5 50 2 4 100 1 1 0

19 82.97 0.68 5 134 0.4 1.7 3 80 20 300 600 10 8 20 0 20 5 2 6 50 0 0 0

21 83.90 -1.27 5 155 -0.3 5 3 0 80 2 10 200 300 10 5 10 2 20 5 0

22 83.87 - 1 5 0 5.1 159 -0,3 4.7 3 0 95 2 10 500 1000 10 4 15 5 20 3 0

1:00 on Station 3:00 on Station, fog 17:00 ship is not moving

!9:00 on Station 21:00 poorvisibility <300rn

22:00 fotlowing HEALY in channel. meltponds Snow covered. fog => bad visibility

Hour

1:oo

14:OO

17:OO

Port Ahead Starboard

Hour

19:00

Ahead Starboard

1:00 mellponds snow covered, fog => bad visibility 3:00 nieltpnds snow covered, fog => bad visibility 12:00 wide lead

20:00 System of leads, pariialiy ramming. some spectacular and high ridges 22:00 following leads in vaious directions

24:00 heading south in old ice regime, ramming from time to time

Hour Port Ahead

Hour Port Ahead Starboard

Data and color images are available via

http://www.awi-bremerhaven.de/Modelling/SEAICE/icereport/index.html

0 - t d U N W N

-4 Tme Wind speed [m/sl

-

Air Tempcrature ['CI

E

Shtp speed [kn]

u _{U U d} u U d Number of Engines

-

^o Operation mode: channet=O,

z*

- u w w +

lead=l, floe ice=3, ramming=4 g

2 '0 3

g po

po g g

Total ice conccniration [%I

'Ln LA C thin ice <30cm [%I

3

2 g

g

5

5

5 &i ^U Dirty ice concentrinion [V.]

g

g g g

Ã

^{g g}

g g g

Lead w d ~ h [m[

- -

W G U , W U W , Lead tlocs, diametcr [ml

,

Typicitl rtdge height [ml

, U M a x . ndgc hcighi [m;

Hour

Port

12.8.2001

Ahead Starboard

Time UTC t-at~tudc ['NI Longitude ['EI Twe Wind speed [mls]

5 s-

E E 5 &

$

&

True Wind d~rection ['I

T O f L Â ¥ Â ¥ L L A Â

$

Air Tempcriture ["Cl

o o S h i p s p e e d [ k n l

0 3

Ln8

^{N W} w w w w w ~ N u m b e r o f E n g i n e s

* g

⁷

-

S- +- + + * , - / J - - Operation mode: channel=O, w w lead=t, fioe ice=3, rammingd

D-

2

^{kg 2 g kg}

^'fi

^g

^{g g g}

Total ice concentration [%]

U Ã ^{U ,} C thin icc < S O m [%I

Y

_U,

_'S : . 2

Typ1c-11 sea ice thickness Iml ^>Ñ

L^

g

à ^{U W} Snow thickness [cmf

Q.

00

i"

4 w m w w L - l

. g

8 8 8 8 8

3

8 8

Typical floediametcr lml

10

0

0

-Si5

E r n - ~ n i - n u w w w

8 8 8 8 8 8 8 8 8

Max. floe diamctcr [m]

0

lÑ

W U . d W

0 0 0 0 Lcad width 5ml

U g

Ã

g Lead floes. diameier [ml

- - -

W Typicat ridge height [ml

+- U ndge height [ml

2 g

g

8

g Typical ridge spacing [ml

- - - - - - - -

ltidges: Ncw=O.OId=l.Both=2

U1 W Rubble fields, coverage

[%I

Icebergs. Number of

Hour Port

Ahead

Starboard

Time UTC Latitude ['NI Longitude ['Ei True Wind spced [ d s l Truc Wind direction ['I Air Temperature !'C[

Ship speed [kni

"

w w N w W W w w Nurnbcrof Engines

-

^A

- - -

Operation mode: channel=O, teiid=!, floc ice=3, ramming=4 S m 4 4 4

g 2 g

g 8 Total ice concentration [%I

m w w w u ^W C thin icc <3&m [%[

, W .

2 ,

Typical sca ice thickncss [ml

-

^N

-

^{4 W N}

-

^{w w Snow} thickncss lcm]

m O w Å ¸ l O O O ' - f l O

3 g g g @ E E

Typic-11 floe diameter [ml

8 ^E

Max. floe diameter [m\

W 5

à à Ã

^{5 5} Melt pond covcrage [%I Typical pond diameter [mi

5 Ã Ã

à à à Maximum pond diameter [ml Dirty icc concentration [%I

S S ^g

Lead width [ml

-

^W Lead floes, diamcter imI

- -

Typical ridgc hcight iml Max. ridge height [ml

- N m - - W

8 5 8 s 8 8 3 8 5

^Typical spacing [ml

- -

Rulges: New=O,OId=l,Both=2

Rubble fields, coverage

I%!

lccbergs. Number of

Hour Port Ahead Starboard

^U=----

Â¥

N m - - -

W

- ^* - ^-

^TimeUTC

m m m m m m m m m m

:C 2

m * * ~ * . l - , 4 m o

b . b + + + + + L d & &

g

g E

2 E 8 & g 8

Longitudc ['EI

2 2 2 2 2 2 .C

Tme Wlnd speed [ d s [

W N

+

- -

^W

-

Tme Wind direction ['I

m m m , , , , , ,

Air Temperature ['Ci

2

^W

[

Ship speed [knj

*

^N W W W W N W Number of Engines

*

+ * + f f - f

-

Operation mode: channel=O.

lead=l. floe ice=3, ramming=4 g g ^g g g g g

8 Ã

Total lce concentration 1%)

, W U U C thin ice <30cm (%I

- .-.

L L L Typical sea ice thickness [ml

0- 6 0

" r 3

* -

W ¹N N N W ^{0 0 *}

-

^{0N W 0} Snow thickness Icml

D. ? %

-

^WWWUUN-N

0-

8 8 8 8 g 8

%

s

Typical floe diameter [ml

. ^{t^}

U

0

5 . 2

Max. floe diametcr [m]

0

lÑ

2

- - -

U D U

-

^U Melt pond coveragc [%I 3

"G U U Ã Ã Typical pond diameter [ml

5-

;

, L-,&..,- Maximum pond diamcter [ml

0,

a Dirty icc concentration [W

Lead width [ml Lead flocs, diaineter [ml

- . - -

W W L V L L Typical ridge height [ml Max. ridgc height [ml

--.-Y W-

s 8 s ^{% %} S 8 S

Typial ridge spacing [ml

- . - - .

Ridgcs: New=0,01d=l.Both=Z Rubble fields, coveragt!

[%I

lccbergs. Number of

Hour Port Ahead Starboard

' -.

;Â

. . .

...

,=---..

_-4:; . . .

,-

--

^{. .}

-

# , , , , ,

...----

L L L L L L L L Air Temperature ["C]

+ Ship speed [knj

W W U W U N U Numbcr of Engines

-

Operation mode: channei=O,

^

lead=I, floe ice=3, ramming=4

2 2 2

g 8 g g Total ~ c e concentration [%I C thin ice <30cm [%I

0.

- - -

^{N N} Snow thickness [cml

"Â¥ o m o ' - " o o o

d.

>

Typical floe diameter [ml

3'

z

LA LA LA W

-

3 $

Max. floe diametcr[m]

¤ -.

-

^{o o w m}

.

Melt pond coveragc [%I

U

W Typical pond diametcr Iml

U Mt~ximum pond diamcter [m)

CA m Dirty ice conccntration [%I

W W W N Lead width [ml

+.

-

0 0 Lcad floes, diamcter [ m ]

- - -

L Typical ridge height [ml

* .E

^{+ W} Max. r~dge height [rn[

2 > >

~ y p i c a ~ ridge spacing Im]

- . - .

Ridges: New=O,OId=l,Both=2 Rubble tields, coveragc

[%I

cebergs. Numbcr of

Hour Port Ahead Starboard

i:00 ice floes are Snow covered

9:00 ponds snow covered, snow covered with ice ernst. ridges badly visible at low contrast 20:00 luge l a d , ponds Snow covered

22:00 ponds and dirty ice are snow covered 23:00 ponds and dirty ice are Snow covered

Hour

1:oo

Port

A h ~ a r i

Starboard

Hour Port Ahead Starboard

20:00 many ponds not snowed but ice covered 21:W new [hin ice forniine in wind shelterd areas

Hour Port Ahead Starboard

Data and color Images are available via

http://www.awi-bremerhaven.de/Modelling/SEAICE/icereport7index.html

1:00 bad is very large, it's not possible to estimate ice characteristics 3:00 dirty ice is snow covered

9:00 fog

17.00 new ice in leads. huge area of open water

Hour

1:oo

Port Ahead Starboard

Data and color images are available via

http://www.awi-bremerhaven.de/Modelling/SEAICE/icereport/index.html

l:00 on station in karge (500m x 500 m) l a d . difficiilt to decribe the ice

3:00 it 1s snowing, ice iioes are coverd by fresh snow. it's difficult to estimate dirty ice 7:00 ndges hard to estirnate (height, distance)

14:00 melt ponds are ice covered with very thin new snow on top. some sedirnents during ice Station 23:00 dense fog, just staned steaming from dredge station

Hour Port Ahead Starboard

Hnur Port Ahead Starboard

g 5

^

True Wind speed [mlsf n E

3' 3'

2 ft= o^

2 00 2

$ 3 True Wind directton ['I

-

^W

"" C

+ 3,

3 ^ ^.'

^Air Temperature {¡C

F F

j S h i p s p e e d [ k n I

g

.q

-

³

5'

g ' W W 4 Number of Engines

Cr W

2: ,

-

,

-

Operation mode: channel=O,

2 0. ^W lcad=l, floe ice=3, rammingz4

3-

^.

2 T 2 Total ice concentration [%I

g 5

C lhin ice <30cm [%[

2 3 S S

Typical floediarneter [ml

2 8 8

Max. r7oe dtamcter[m{

-

G2

's 8 8

; Melt pond coverzige [%I

%

- -

Typiciil pond diameter lml

à ^{à Ã}

g

Maximum pond diameter [m]

m Dirty ice concentration [%I

8

K) 6 Lead floes, diamcter [ml

- - -

L L L U U

- -

Typical ridge height [ml

W bJ lcebergs. Number of

Data and color images are available via

http://www.awi-bremerhaven.de/Modelling/SEAICE/icereport/index.htmI

N

Â¥3

-

z

I 85.08 10.73 2.9 235 -2.4 1.6 2 I 3 85.13 10.92 2.4 220 -3.2 0 2 1

6 85.07 1207 2.3 186 -3.3 2.1 3 2+3 60 2 10 20 100 10 5 10 200 5 2 4 20 1 7 85.08 12.45 3 206 -3.1 5.7 3 1 55 5 5000 5000 70 15 50 5 150 10 2 3 50 1 14 85.18 13.97 5.2 95 -1.5 4.8 3 1 50 1.8 5 100 2000 20 10 50 50 200 50 1.5 4 200 1 1 2 20 85.23 1 3 7 0 6.5 177 -3.1 5.8 3 1 70 1.5 5 200 1000 20 10 30 10 50 40 1.5 5 200 1 1

21 85.25 14.40 6.5 175 -2.9 4.7 3 I 6

22 85.27 14.78 7.7 170 -2.9 7.9 3 I l

23 85 30 15.87 6.4 183 -2.5 6 3 1 70 1.4 150 800 10 5 40 5 200 10 1.5 3 300 2 4 : 0 0 on Dredge Station, we work in luge lead, strong fog. very poor vistbility

3:00 on Dredge 'itdtion, we work in Iarge lead, strong fog, very poor visibility 6:00 much Open water

7:00 new ice formdtion, fog, far as visible: just water, no ice

1 4 : N very foggy: 2 icebergs very closely passed, probably more in the vincinity; green and blue ponds. some melted through, many algae and some floes are sedimented 20:00 very foggy; green and blue ponds. some good icebre'aking

21:00 huge ice free area and very poor v~sibility, 2 Sarge icebergs > 50m 22:00 very poor visibility, fog. operating in big lead

23.00 fog. poor visibility

Hour Port Ahead Starbnarfl

22.8.2001

Hour Port Ahead Starboard

Truc Wind speed [ d s l

5 - - -

5

True Wind direction ['I

2 g;

Shipspced [knl

-

W Numbcr of Engines Ã

m

-

Operation mode: channel=O,

+

W

- +

W lead=l, floe icc=3, ramming=4

2

³ Total ice conceniration [%I C lhin ice <30cm [%I

L

Typical sea icc thickness [ml 6 Snow thickness [cml

Typical floe diiuneter {m]

Max. floe diamcter [ml

2 g

Melt pond coverage [%I Ã Typical pond dianieter [ml

g g

Maximum pond diameter [ml Dirty ice conccntration [%I I m d width [ml Lead flocs, diametcr [ml Typical ndgc height Ern]

. Max. ridge height {mi Typical ridge spacing [ml R Q o : Ncw=0,01d=l,Bolh=2 Rubble fields. coverage

[%I

Icebergs. Number of

Data and color images are available via

http://www.awi-bremerhaven.de/Modelling/SEAICE/icereport/index.html

13:00 spaces between oldcr iioes are filled with thin ;snd undeformed FYI, \ery evenly ponded with most ponds melted through 16:00 operating in big lead, dirty ice not dctectible

19:00 in open water. fog, hard to estimate ice situation. no wind data 20:00 fog and giant lead - 1.5 X 7 km large

21:00 sunnyl

Hour Port Ahead Starboard

Hour

Port A h-ti

Starboard

6:00 some new ice formation 1 2 0 0 Petrology station, clear sky!

15:00 good visibility, very homogeneous floes with few ridges. green and baue ponds, 17:00 on station

Ilour Port Ahcad Starbourd

1:OO

Hour Port

12:00

15:00

16:00

17:00

21:00

Ahead Starboard

TNC Wind spccd [m/s)

N N - N N N

à Ã

^{8 8} TNC Wind dircction [¡

6

0 0 0 ₀ Air Tcmpcrature [¡C

W W N - W N -

8

Ship spccd [knt

W W W 4 N N Number of Engines

-

Operation modc: channeld.

-

lead=l, floc icc=3, ramming=4 g

2 2 2

g Total icc concentration [%J

C [hin icc <30cm [%I Typical sca icc thickncss Eml Snow thickness icml Typical fioc diametcr [ml Max. floc diamctcr [mt Mcit pond covcrage 1%) Typical pond diametcr [m]

Maximum pond diameicr [ml Diny icc concentration [%I Lead widlh [mj Lead flocs, diamcter [ml Typical ridge height [ml Max. ridge height km1 Typical ridge spacing [m]

Ridgcs: New=O,Old=l,Both=2 Rubble fieids, coverage

[%I

Iccbcrss, Number of

0:00 on station, fog, bad visihility 3:00 on station, foa. bad visibilitv 37:00 fog, sediments

20:00 mixture of very level. greyish and very ridged floes: many ponds melted thmugh. it seems that many ridges are formet! by blocks of very thin ice. no sediments 22:00 many pressure ridges, ship is ramming

Hour

1O:OO

14:OO

16:OO

Port Ahead Starboard

Hour Port Ahead Starboard

 ¥ ? 2

. Ship speed [knl

W W W W W i Number of Engines Operation mode: channcl=O.

- - -

^{+ - + %}

W li;dd=l, floe ice=3, ramming=4 g , Total ice conccntration [%I

C thin ice < 3 k m [%I

- - - -

. .

2

Typical sea ice thickness iml

t^>

à à à à Snow thickness lern1

00

₀₀

2 2

Typicai floe diamctcr [ml (0

0

2 2 >

Max. iioe diameter [ml

0

lÑ

& 8 &

Mclt pond coverage [%I

W W Typicdl pond diiimetcr [ml G

5 5

g

s E

Maximum pond diametcr [ml

0 Ln Dirty icc conccntration I%!

- - - -

Typical ridgc hcight Iml

W Mdx. ridgc hcight Ern1

- N N -

g g g 8

g

8 g

Typical ridgc spdcing lml

- -

Ridges: New=O.OId=l.Boih=2 Rubble tields. coverage

[%I

lcebcrgs, Number oi

Hour

Port Ahead Starboard

Time UTC Latitude ['NI Longitude ['EI Tme Wind speed [ d s l Tme Wind direction ['I Air Temperature ['C]

Shipspeed [kn]

' W W W W Numher of Engines

-

^o Operation mode: channel=O.

- - + + D

0 W lcad=l, floe ice=3, rammingd g g g Total iceconcentration [%I

C thin ice <30cm I%]

;

Typical sea ice thickness [ml Snow thickness [cml

WWNNW

8 8 8

8 Typical floe diameter [m]

8 8 ^$

Max. Roc diarneter lml Melt pond covcrage [%I Ã ^Ln Typical pond didnieter [ml

& &

^; Maximum pond diameter [m]

-

Dirty ice concentration [%I

g

^g Lead width [rnl Lead ilocs. diametcr [ml

W

-

Typiczil rndge height [ml Max. ndgc height lml

9 ^{2 2}

Typical ridge spacing [mi

- -

^W

.

Ridges: New=0.01d=l.Both=2 Rubble tields. coverage

[%I

-

^2.t

m 4 D Icehergs. Numher 01

4 - & * & X * * * * * *

^) L 4^ <o '-n

Longitude ["E]

U W m < m m " < m o

) ) True Wind speed [mlsl

N N N N N W ' W W

N N

-

^{N o U}

-

^m

-

^4- Tme Wind direction 1'1

m 0 ^ 0 W m o m U 4 <

2

Air Temperature [¡C

.

2

Ship speed lknl

4- .hi -C, .fà 4- W W W W NumberofEngines

0 + O O * * * O O O O Operation mode: channel=O, lead=l, floe ice=3. ramming=4 g \0 Total icc concentration I%[

- - -

C thin ice <30cm [%I

N N N o m ' a m

<o

Typical sea icc thickness lm!

U Ã Ã

5

Snow thickness [cml

W W

8 5 E 8 8 8 2

Typical floe diameter [m[

w w w m m u

8 8 8 8 3 3 8 2

Max. floe diameter [ml

- - -

^{W W W}

- - -

^N Melt pond coverage [%I

' a 0 0 O 0 0 U : ~ o o

- - -

^N , , Typical pond diameter [nil

N o

g

Maximum pond diameter [m]

U Diny ice concentration [%I

N .W W

-

^.W

_g 8 g

Lead width lml

U U

-

o Lead fioes, diametcr [ml

- - - - - - - ^G -

Typicitl ridge height [ml

W Max. ridgc height lml

1 8 8 8 8 8 8 ²

Typical ridge spacing [ml

, - - -

Ridges: New=O,OId=l.Both=2 Rubble tields, coverage [%I

- -

^{^3} Icebcrgs. Numbcr of

Hour Port Ahead Starboard

E OST SE 5'z 01 00; 001 8 Z OSZ S ' I I 01 OZ 01 SI OOOE 0007.

ZI I 00; S Z 08 O t S OE OOOS 0005

OZ OE 01 51 OOOE 0001

01 OE 01 SI OOOE 0001

OOi

z

I Z 01 01 S S I 000z 00s 001

z

I

z

01 01 S SI 000z 00s I

i  L'I /.'E- £0 L'Z LZ'6P 01 S'I 08 Â¥ Â¥ V\ V I - Z9 Z S6'Lt SI Z S 56 t+O Â¥ V I Z'E- L9 VT. L5'W 01 Z 5 56 0 t- 5'1 Z'E- ZZE 9'1 85'6r S 5'1 Z S6 0 0 0 9'1- 9t'E 1 Z8'8b 5 5'1 Z 56 0 V Z'f- I '  £ 6SE E'I LE'8à 01 5'1 S6 0 Â¥ VE L'Z- SSE 8'1 S9'8f' E S'l S6 0 Â¥ L'E S'Z- U E L W

Hour

8:OO

14:OO

15:OO

16:OO

Port

31.8.2001

Ahead Starboard

Time UTC

Longitude ['E]

True Wind speed [m/s1 True Wind direction ['I Air Tcmperaturc ['C]

Ship speed [kn]

Numbcr of Engines Operation mode: channel=O, lead=l, floe ice=3, ramming=4 Total icc concentration [%I C thin icc <30cm [%I

Dirty icc concentration [%I

g

UJ L-; Lead width [ml

g

5 0 Lead floes. diametcr [m!

- -

L L L L Typical ridge height [ml

~ W W W W WMax. ridge height [ml

- N N N - N

8

8 8 8 8

8 Typical ridge spacing [ml

,

Ridges: New=O.OId=l.Bo!h=2 Rubble fields. coverage

[%I

Hour Port A head Starboard

*<

-

h - -

-

^ÑO

'"Â¥

m

0 86.90 63.37 3 316 -0.4 0.5 I

3 86.83 M W 3.8 60 -2.4 3.7 3 1 90 1.8 10 200 1000 10 5 10 15 5 1.5 2 60 2 2 4 86.80 653.5 2.7 58 -3.5 4 9 3 0 oft 5 2 I 0 IWO 5000 3 0 I 0 40 30 5 I 2 50 2 I 5 86.73 65.98 5.3 86 -3.3 4,9 3 0 95 5 1 7 5 200 2000 5 10 30 50 30 1 3 200 1 1 3 6 86.73 66.63 2.2 83 -3.4 3.4 3 1 95 5 2 10 300 1000 5 10 30 50 30 1 3 200 1 1 3

21 86.72 66.72 2.6 92 -4.1 2.4 3 4 oft 5 2.3 8 300 2000 l 2.5 300 2

I 5 86,68 67.85 2.9 105 -5.5 1.3 4 l+4 oft 5 2 15 400 2000 5 10 15 5 20 15 1 1.5 200 2 5 I 6 86.65 68.80 1.9 100 -4.9 4.9 4 1 90 10 2 15 250 1000 300 2.5 4 200 2 22 8657 70.00 2.9 I 3 6 -5.4 5.4 4 1+4 95 5 1.3 15 300 2000 20 5 25 0 150 10 1 3 200 2

23 86.62 70.48 2.5 156 -5.3 1.5 4 4 95 3 1.3 15 300 1000 50 1 3 5 0 2

0:00 waitingfor HEALY, it 1s snowing, very poor visibility 4:00 ponds snow covered

5:00 frozen ponds appear greyish due to last days snow and rain 16:00 new ice

22:00 melt ponds are fresh Snow covered, new ice formation 23:00 melt ponds are fresh Snow covered, new ice formation

Hour Port Ahead Starboard

Hour

15:OO

Port

Ahead Starboard

17:00 ponds parlially Snow covered. HEALY sometimes needs to ram 21:00 ice floesare fresh snow covered, new ice Formation 23:00 ice floes are fresh Snow covered, new ice formation

Hour Port Aliead Starboard

r

t*'"-";.,

.

^{. .}

*;-.

15:OO LÈ"

^'

^*. . '

Data and color images are available via

http://www.awi-bremerhaven.de/Modelling/SEAICE/icereport/index.html

*

c-4

5

-

- ^{- O E} -

3 87.02 76.52 4.7 247 -2.7 6.6 4 0 90 5 1.6 20 2000 1000 2 0 5 1 3 1 0 0 2 I

4 87.10 77.02 3.7 239 -2.7 5.7 4 0 90 5 1.8 20 300 5000 20 10 2 3 250 2

5 87.18 77.95 2.5 205 -2.8 7.1 4 0 90 5 1.8 20 300 1000 20 10 2 3 250 2

9 87.47 80 12 2 213 -4.4 5 4 0 90 1 5 20 300 2000 40 10 2 3 250 2

10 87.55 79.98 3.9 205 -4.3 5.2 4 0 100 10 2 15 300 2000 100 50 1 2 200 1

12 87.60 82.10 2.9 180 -6 4.6 4 0 90 15 1.8 15 500 800 30 5 1.5 2 150 2

15 87.80 82.15 3.8 190 -6.5 4.6 4 0 90 10 1.8 20 1500 2000 20 2.5 4.5 20 2 16 87.87 84.80 3.6 179 -6.2 5.5 4 0 100 20 2 15 500 2000 100 20 l 4 200 2 18 87.93 84.82 4.5 164 -7.1 6.9 4 0 100 20 2.2 15 400 5000 50 5 I 2 5 300 2 21 88.12 88.73 3.5 181 -5.3 6 2 4 0 98 40 1.8 15 200 800 100 10 1 2 100 2

23 88.23 92.43 4.2 189 -4.5 9 4 0 100 20 1.7 20 300 2000 50 10 1 2 200 2

9:00 a day for adaydream :-)

10:00 ail ice coverd vvith Scm powder snow. all water covered with nilas l2.00 fog

15:00 following HEALY

16:W ail Open watercoverd with nilas, long system of leads 21 :00 ice floes are Snow covered (fresh snow). new ice formation 23:W ice floes are Snow covered (fresh snow). new ice formation

Hnur

Port Ahead

Hour Port Ahead Starboard

0 0 0 0 0 0 0 0 0 0 0 Operation mode: channel=O, Iead=l, floe ice=3, rammingz4

8 8 5 8

Total ice concentrauon [%I

- - - - - - - - - - ^*

C thin ice <3(km [%]

O ' - i i O O O ~ 0 ' & Å ¸ i O

- -

W W W W W W Typical sea ice thickness [ml

L/l

o

-----o -WW o o ,& W - o ,&

g

Snow thickness [cml

\0

6 4

3 8

Typicat fioe diamctcr [mj

0

0 )

Max. fioe diamecer [ml F

Ÿ Melt pond coverage [%I Typical pond diameter [ml Maximum pond diameter [ml Dirty ice conccntration [%I

Hnur Port Ahead Starboard

3:00 it's snowing

Hour Port Ahead Starboard

Data and color images are available via

http://www.awi-bremerhaven.de/Modelling/SEAICE/icereport/index.html

5:00 ponds not visible. staeming wilhout HEALY

i5:00 very foggy, poor visibility, max. floe size and ^% ice coverage hard 10 estimate 18:00 fresh snow cover, no melt ponds visible, transit to Station

Hour

2:oo

Port

Ahead Starboard

Hour Port Ahead Starboard

-4,-

) T m e W i n d s p e e d [ m / s ]

2 0 $ 8 '

E N u w w , . w U U U U

g >

^{^o \o G}

^{^o 2}

^{g 3} Tme Wind direction 1-1

5.2

L + + + , , , , ,

g.

^,

^-i

, ^{L*' ^ 5}

Air Temperature [¡C ¥ 7 %

0

*

Ship speed [kni

S s

b"-"t^4^boOO

L"&.

<

^{o .}

a

^{U w U} Numberof Engines

+

k * U . d E - & . , d U o Operation mode: channel=O,

-

lead=i, floe ice=3, ramming=4

g % 3 g g

E

^{\o \o g} Total ice concentration [%I

..

³

2

-

- - C t h i n u c d O c m l r i I

-

- - C ' * = , = - = - -

\ - - - . ^{- -}

^{^,}

^{- -}

^.

^{- - - ,}

^{Typicdl \<:I} I:? 1htckne-i-i Iml

> & - -

< = = , C = = = .^,

=

^{^, Sn.ià ~hi:kn:,, 12mI}

-

& & , - & ' J , * % X -

-

_i'bpi~d! flin; dumeter lml

.-

-3

_- ' - - - - ~ '

^{L - -}

~ 3

_{\IJX fix}

'

J i ~ m c l c r

'

In11 I

5

,- - ,, - - =

^{' A Meil pond m:r:tg: tri,]}

T;

- - - -

C l

- _{- -} -

A O

,

T\pi2.i! pond Juni.-[er lml

- ,., -

-

^{C ' A} M ~ x i m u m pond di-im.:k-r lrnl

-

^{Um\ iii-C} ~ o n ~ c n l r t i ~ d n 1'21

-

H

3

'S

5 g

g

g

8

⁵ L a d width [ml

à U. N

Â¥- o U. o

8

Lead flocs. diameter [ml

3

Ñ

- ,.

^{U H}

-

Typical ndge height [m!

&.

,.

^&.

, ,

Max. ridge hcight [ml

-

- , . , - - W

8 8

g

8 8 g g g g

Typical ridge spacing [m!

E

, , , ,

^{W W}

, , , ,

Ridges: New=O,Old=l,Both=2

C

8 ^H

-

^U Rubble ftelds. coverage [%I

&. 0 0 0 lcebergs. Number of

g

Hour

17:OO

Port Starboard

3:oO conditions difficult to judge 9:00 conditions difficult to judge

11:W poor visibility < 300m 13:00 fog

14:00 fog 15:00 fog

16:00 ponds frozen and snow covered, but visible

l7:00 pressure ridge Formation, ship stuck, lots of algae on ice underside (red) 21:00 pressure ridge formation, ship stuck, lots of algae on ice undcrside (red)

Hour

13:OO

Port Ahead Starboard

Hour Port Ahead Starboard

21:00

_,

,

Hour

fog, only very few green ponds visible from helicopter. new ridges at floe contacfs fog and poor visibility

fog, white out, difficult to estimate fog

only some few green ponds are snow free visible: still much ramming; new ndges at floe contact POLARSTERN got stuck

ramming in ice, fog, algae in broken ice still ramming, some melt ponds without Snow Cover on station

Port Ahead Starboard

Hour Port

2:00 only few rnehponds visible, many ridges formed by rarnrning 9:00 POLARSTERN got stuck again, snowfail

10:00 snowfall and fog; very few snow-free green ponds, others partiaily visible: ice under pressure, new ridges at fioe COntaCl I 1:00 strong snowfali, mainly horizontal, big snowflakes, on station

13:00 ship on staion, fresh Snow fall 15:00 snow, poor visibility

16:00 20% melt pond Cover. snow and ice covered, greyish; ice under pressure 17:00 still ramming at Same position

21:W on station, fog, poor visibility 23:W on station, it's snowing, poor visibility

Port Ahead Starboard

Data and color Images are available via

http://www.awi-bremerhaven.de/Modelling/SEAICE/icereport/index.html

Data and color images are available via

http://www.awi-bremerhaven.de/Modelling/SEAICE/icereport/index.html

Time UTC Lautude ['NI Longitude ['E)

Hour Port Ahead Starboard

Hour

23:OO

Port Ahead Starboard

Data and color images are available via

http://www.awi-bremerhaven.de/Modelling/SEAICE/icereport/index.html

3:W on station 14:00 fog 16:W on station 21:00 new ice fonnation 23:W fog

Hour Port Ahead Starboard

Hour Port Ahead Starboard

12:00 on station

15:00 got stuck, ice thickness estimated from broken ice around the ship 16:00 still r m m i n e throueh two bie floes > 2km diam. with bie fresh ridse inbetween 17:00 stuck again, ramming

21:00 on station

23:00 on station, fog, poor visibility, new ice formation

Hour Port Starboard

Hour Port

-.

.

3 ^B

3.

_.

2 S

T m Wind speed [mi?,]

s 3

i.

2 L d w w , . , J L a - - W

Â¥

3 ; 2 Ã : ^g

g g 8 Tme Wind direct~on ['I

7 "

5 5 5 2 t',, 5 c/.

Air Temperamrc [¡C

g"

2

^B, U

2 2 \

Shipspeed [kn]

u m

2 3 ^* * * * * * * * * *

Numbcr of Engines

W W - P , * - & . . - A I . .t^-t^-ciw Operation modc: channei=O, lcad=l, floc icc=3, ramming=4 g 2 E

s

g g g 3 g g g Total ice concentration [%I

à W U C thin ice <30cm 1%)

- - - -

W L G L L G L L L W Typical sea ICC thickncss [mf

à Snowthickness[cml

1 3 E ,$ s

Typical floe diamcter [ml

~ M a x . f l o e d i a m e t e r [ m ]

- - - W . . - . . .

U U MeJt pond coverage [%I

- - - -

U C U U W U U U Typical pond didmcter [m]

g

g 5 g

g

g 5 3;

g s s

⁵ Maximum pond diameter [m]

o o W Dirty ice concentration [%I

* * U m m

0 0 0 0 0 Lead width [m]

r " 8 Ã 0

Lead floes, diamctcr [ml

- - -

Typical ridge height [ml

W W >Â¥-

E

W Max. ridge height [ml

- W L a W U - W - -

8

2

8 8 8 8 2 8 2 2 2 Typical ridge spacing [ml

W W Ridges: New=0,01d=l,Both=2

0 Rubble iields, coveragc [%I

< W

-

Icebergs, Number of

w W W Operation mode: channel=O,

* * * * * * + * * * + +

iead=l, floe ice=3, ramming=4

- 0 0

g

g g Total ice concentration [%I Ã C thin ice <30crn [%I

- -

Typical sea ice thickness [m] ^lÑ

4

à à à à G Snow thickness lcrnl

, L d w - - - w w w w

9

8 8 8 8

2

8 8 8 8 Typical floe diameter [ml

W 0 0

g E 3 3

Max. floe diameter [m] hÑ

Melt pond coverage [%I Ã , Typical pond diarneter [ml

-

^N

-

^{N N} Maximum pond diameter [mj

0 0 0 0 0 0 0

0 0 Dirty ice concentration [%I

N

-

^{w N W N} Lead width [ml

0 0 0 0 0 0 0 0 N 2-

U 0 0 Lcad floes, diameter [mj

----W

-

^M

^-

Typical ndge height [mf Max. ridge height [ml

g g 5 ^g

Typicai ridge spacing [m)

, , , , , , , ,

Ridgcs: New=0,01d=l,Both=2 Rubble fields. coverage [%I

.

Z ^I 00 Icehergs, Nurnber of

Hour Port

17.9.2001

Ahead Starboard

1:00 new ice formation in leads

15:00 poor vissbitity, snowfall. new ice forming in l a d , on station l7:00 poor visibility, snowfall, new ice forming in l a d , on station

18:W very foggy, ramming between two big floes. ponds weil visible by their white Snow Cover in contrast 10 greyish bare ice surface, bigger ponds are snow free 21:00 heavy snowfall, dark

23:00 heavy snowfall, bad visibility

Hour Port Ahead Starboard

Data and color images are available via

http://www.awi-bremerhaven.de/Modelling/SEAICE/icereport/index.html

l 86,53 40.37 9.7 107 -3.5 0 2 4 100 15 1.8 10 4 6 5 2 40.10 8.8 343 -3 4 100 2 10 1000 2000 5 86.50 40.62 7.3 99 -2.7 3.1 4 100 1 1.5 10 1000 2000 11 86.45 41.17 1.5 109 -2.1 7.9 4 4 100 10 1.5 10 1000 2000 12 86.43 41.98 5.5 267 -3.3 4.5 4 98 5 2 15 500 2000 13 86.43 40.98 6.5 266 -4.9 0.2 4 98 5 1.6 10 15 86.42 40.97 6.9 270 -5.6 95 2 1.8 15 300 2000 16 86.42 41.08 6 268 -5.7 100 10 1.5 10 300 500 17 86.40 4118 6.4 270 -6.3 0.9 4 4 98 5 1 8 10 300 500 18 86.42 40.48 4.6 255 -5.9 6.4 4 3 98 10 1.8 15 200 1000 19 86.42 40.60 4 3 239 -6.2 2.2 4 4 98 5 1.5 10 100 800 23 86.40 40.73 3.7 272 -5.6 0 2 4 98 10 1.7 15 200 1000 1:00 heavy snowfall. bad visibility

4:00 poor visibility, snowfall 5:00 poor visibility, snowfail

12:00 preparing for Dredge Station, mosi ponds covered with new snow, no more visible 13:00 on station

15:W an station 16:00 on Station

18:00 most ponds covered by new snow, thick, favourable ice condition for steaming 19:00 getting dark, mett ponds covered with snow, not possihle to see them. Snow drift 23:00 ponds are fresh Snow covered

Hour Port Ahead Starboard

Hour Port Ahead Starboard

13:OO