ࡱ > U@ ~ bjbj ) ` \ \ \ \ 8 0 " X X ( ? F n" $ # R % J " @ " \ \ I " p \ 8 | L m: 5 d " 0 " ?( 4 ?( $ \ \ \ \ ?( 8 d m k 7 " " $ Science Report Aug 2 - Aug 13, 2005 NGCC Des Groseilliers Barrow Strait Through-Flow Study Oceanographers from the Bedford Institute of Oceanography (BIO) joined the NGCC Des Groseilliers at Resolute to carry out the eighth year of fieldwork in an ongoing ocean climate study. The primary goal of the study is to determine the seasonal fresh water transport through Barrow Strait, and the nature of the variability of this quantity from year to year. Barrow Strait is one of 3 main passages through the Canadian Archipelago connecting the Arctic Ocean to the Northwest Atlantic, providing a principal pathway for any increased freshwater discharge from the Arctic Ocean that may result from a climate-warming trend. (See Figure 1 for a map of the study area). The current, temperature, salinity and water level data being collected are also being used to improve our understanding of the oceanography in this area, and to validate circulation models. In this way it will aid in the prediction of ice movement, and be useful in the development of navigational tools and spill contingency strategies. Science program objectives for this mission were 1) to recover eleven moorings and then replace those with an array of nine; 8 across Barrow Strait at 91( W (see Figure 2), and 1 south of Resolute, 2) to complete a 35 station CTD survey in Barrow Strait and Wellington Channel, and 3) to collect water and ice samples for laboratory analysis. Nine of the eleven instrumented moorings were recovered. Preliminary analysis shows that the 5 acoustic doppler current profilers with their custom instrumentation for measuring direction in this near-pole environment performed well. Data sets from 11 of 12 moored ctds and the 3 recovered tide gauges also look good. However, one tide gauge was not recovered due to a release failure. Excellent ship handling in broken ice cover with homemade grapnels from the engineering department resulted in us hooking this mooring twice in dragging operations, but alas it got away each time. It will be there to try for next year, perhaps in better ice conditions and with the grappling equipment we usually have with us! We were also unable to recover our upper ocean profiler, Icycler. After dragging the mooring location, and performing an acoustic survey in the local area in an unsuccessful search for the mooring release, it seems most likely that this mooring was carried downstream by ice. Given the 5-year battery life of the acoustic release with its ability to send an acoustic response when interrogated from a range of up to 3 km, plus our knowledge of the ice movement and currents in the area, we plan to do an extended search for this mooring with towed acoustic equipment when we return in the summer of 2006. Mooring deployment operations went smoothly in calm, ice free conditions. Included in the deployed instrumentation was the prototype Icycler successfully used in 03-04, and an Ice Profiling Sonar. All 3 planned CTD lines were completed. These were the Eastern and Western Barrow Strait lines at 91( W and 94( W respectively, and the Wellington Channel Line at 74( 50 N, for a total of 35 stations. Six water sampling stations were also completed, one at each of the 4 Barrow Strait mooring sites along 91( W, one in Wellington Channel, and one along the Western Barrow Strait line. Each station consisted of taking water from 4 depths. These samples will be analyzed to help determine the sources of the freshwater passing through Barrow Strait. Once again this year, we are indebted to the solid effort, cooperation and interest of the captain, officers and crew of the NGCC Des Groseilliers. I thank them for a successful and enjoyable trip. I also thank CCG Ice Operations Coordinators in Sarnia for their effort in fitting us in to the Arctic operations plan and coordinating the transport of our equipment. Jim Hamilton Bedford Institute of Oceanography August 14, 2005 Figure 1. A map of the work area showing the mooring locations (the open boxes), and the hydrographic survey lines (the dashed lines). Figure 2. An illustration of the Mooring Array at the Eastern End of Barrow Strait replaced in 2005. PAGE 3 PAGE 4 < _ | + 2 : g e H I ' ( D F G P S T U ` a 䳢ꛕ{ j hH 0J Uj hH CJ UmH nH u hH CJ hH 5CJ !j hH 5CJ UmH nH u hV|r CJ h3b CJ hH h} CJ h$h; CJ hvs CJ h CJ j hH CJ hH CJ hH 5CJ h hH 5CJ mHsH / & < ] ^ _ U | ? ' D E F ^` d @`^@`` dh ^` dh ` dh $dh a$ ` { } L M N O P S T V W X p^p ^` ^ ^` X Y Z [ \ ] ^ _ ` k l m x y z { | } ~ &`#$ d p^p a g h i j k m n t u v w x z { } ~ hH CJ hV|r hV|r 0J mH nH uhH hH 0J mH nH uj hH 0J U hH 0J ( 00:pV|r / =!"#$p% FY ~{i@ƛ?zc JFIF aExif MM * n v( 1 ~2 i Adobe Photoshop 7.0 2005:01:06 13:01:15 x " *( 2 ' H H JFIF H H Adobe_CM Adobe d ? " ? 3 !1AQa"q2B#$Rb34rC%Scs5&DTdE£t6UeuF'Vfv7GWgw 5 !1AQaq"2B#R3$brCScs4%&5DTdEU6teuFVfv'7GWgw ? 4n005[\ !swo:=gKYm6@}_쩵>eCѯ 7z/RY؟i}~ֲa=+\ܭ̾ߦRoUwH-zWSG?4oP1$_'wOߟKo*"D.(`x:};m'ۼ{Vm~M-p^ꐝ:x$595cʬsK`hkMk]ukZ\r,o/J=h/֍,b$lFﱺ S{}۵Ղ\4{y5g_ޚO_GtIpE E f귌t-(`= 5^@k ikH#fQ! %fD }k/So]C5iٻw{?88ݰ!Ws^cFduu]k-7 uup#~ ]U`%m8o?Bȴ`k?;kZ/tm]z0m{6ȗ;Wkl+wzVhָ xw2Ua W&J'/ G(KOᄇ d9M\\v;,kkc [R n~;7h9+C 5 sА&wqjd#b"Xg{= F;V[3)},C'}v/IweeT2sӐn}4۶ 3Uk[c^ùsO TFz<_MU8ݲV2dc} z2Ǐg5ޔWNY%8.