Marginal Ice Zone (MIZ) Program

Successful Field Season Ends

Autonomous Robots Deployed

Program Motivations

We have this amazing picture of the ocean, atmosphere, and ice going from the fully frozen period in March to meltdown and breakup right through to freeze-up in early autumn.

This picture of the physical system changing over time was made possible by the deployment and persistence of many robotic platforms over the seasons.

Martin Jeffries & Scott Harper Discuss Program Motivations
Martin Jeffries & Scott Harper Discuss Program Motivations		The Arctic and Global Prediction program is ONR's response to the Navy's need for more research into understanding the environment and expanding our predictive capabilities. We've been investing in new observing systems to understand what is going on in the Arctic. The Navy expects to operate in all the world's oceans. Because of the opening up of the Arctic during summers, the Navy anticipates that it will have to send surface vessels to the Arctic for miliatary or other emergency purposes.

Overview

Recent decades have seen pronounced Arctic warming accompanied by significant reductions in sea ice volume and a dramatic increase in summer open water area. The resulting combination of increased ice-free area and more mobile ice cover has led to dramatic shifts in the processes that govern atmosphere–ice–ocean interactions, with profound impacts on upper ocean structure and sea ice evolution. The summer sea ice retreat and resulting emergence of a seasonal marginal ice zone (MIZ) in the Beaufort Sea exemplifies these changes and provides an excellent laboratory for studying the underlying physics.

The Office of Naval Research MIZ initiative employs an integrated program of observations and numerical simulations to investigate ice–ocean–atmosphere dynamics in and around the marginal ice zone in the Beaufort Sea. The measurement program exploits a novel mix of autonomous technologies (ice-based instrumentation, floats, drifters, and gliders) to characterize the processes that govern MIZ evolution from initial breakup and MIZ formation through the course of the summertime sea ice retreat. The flexible nature and extended endurance of ice-mounted and mobile, autonomous oceanographic platforms allows the array to follow the MIZ as it retreats northward, sampling from fully ice-covered waters, through the difficult MIZ and into the open water to the south. The nested array of drifting and mobile autonomous platforms resolves a broad range of spatial and temporal scales. By remaining focused on the MIZ as it retreats, the array resolves changes in the physics associated with increasing open water extent.

Navy funds a small robot army to study the Arctic

NPR, Geoff Brumfiel

Climate change is causing the Arctic Ocean to thaw. The Navy is paying researchers to develop gliders and other gizmos, and stick them in and near the ice, because it needs to figure out how quickly the thaw is coming.

15 Feb 2015

Science Objectives		Technical Objectives
Understand the physics that control sea ice breakup and melt in and around the ice edge Characterize changes in physics associated with decreasing ice/increasing open water Explore feedbacks in the ice-ocean-atmosphere system that might increase/decrease the speed of sea ice decline Collect a benchmark dataset for refining and testing models		Develop and demonstrate new robotic networks for collecting observations in, under, and around sea ice Improve interpretations of satellite imagery Improve numerical models to enhance seasonal forecast capability

Current Array Position		Current Array Data
		Cluster 4 Cluster 3 Cluster 2

Large Scale MIZ Evolution

Radarsat II, ScanSAR Wide

500 km x 500 km scene, ~100-m resolution, dual-polarization when available (HH,HV)

Latest Radarsat-2 image

Buoy Clusters

TerraSAR-X, Single-Polarization StripMap

30 km x 50 km scene, 4-m resolution (HH)


Latest image of Cluster 1 Latest image of Cluster 2		Latest image of Cluster 3 Latest image of Cluster 4

Data Description

A document including a detailed description of the imagery collected and instructions for obtaining full-resolution images from the CSTARS is available to the project's Principal Investigators in the Collaboratory.

Visible Images

High-resolution visible images (18 km x 18 km, ~ 1-m resolution) are being collected by MEDEA to monitor ice conditions in the immediate neighborhood of the buoy clusters and the BGEP A and D moorings.

These background images are collected every three days through the height of the melt season (July–Sep) and collected every seven days prior to this. The visible images will be available on the USGS Global Fiducial Library once they are approved for public release.

ITP

Data from all Ice-Tethered Profilers with Velocity (in near-real time)

AOFB

Data from all Autonomous Ocean Flux Buoys (in near-real time)

SWIFTs

The Surface Wave Instrument Float with Tracking — SWIFT — is a free-drifting system to measure waves, winds, turbulence, and ambient noise at the ocean surface.

SWIFT Tech Specs & Operations

IMB, WB, and AWS

Public data will be available soon.

Atmosphere–Ice Coupling in the Evolving MIZ
One of the more obvious impacts of the changes in ocean–ice–atmosphere interaction in the Beaufort and Chukchi seas region has been the expansion of a MIZ; a long-standing feature in the Bering and Chukchi seas, but a relatively new phenomena in the deep Beaufort Sea. In the western Arctic, the northward retreat of the sea ice edge increases the open water area, allowing direct momentum transfer from the atmosphere to the ocean surface through wind-driven waves. The resulting fragmented ice field has different surface roughness features, and because the smaller floes are significantly more mobile, sea ice can absorb more atmospheric surface stress through deformation and transfer it to the ocean surface. More efficient atmosphere–ocean coupling in regions of partial ice cover and open water can amplify upper ocean mixing far beyond levels observed under full ice cover. As in the open ocean, strong winds acting on ice-free regions of the Arctic will drive turbulent mixing that deepens the surface mixed layer, entraining waters from below. Because the sea ice cover moderates atmosphere–ocean fluxes and the ocean affects the ice cover through fracturing, divergence, and melting, the ice–ocean system is strongly coupled within the MIZ. Key upper ocean processes that contribute to strong coupling: Propagation and attenuation of ocean surface waves Absorption and storage of incoming solar radiation and its subsequent lateral transport Vertical mixing within and at the base of the ocean mixed layer		Atmosphere, ice, and upper ocean processes in the MIZ. Ice cover modulates penetration of solar radiation and isolates the upper ocean from direct wind forcing, but increasing open water within the MIZ, and the proximity of large expanses of open water immediately to the south, permits more direct connection with the atmosphere. Strong open water swell and surface wave activity attenuates as it enters the MIZ. Likewise, internal waves, submesoscale eddies, and mixing weaken with increasing ice cover. Small-scale windstress curl associated with ice to open water transitions and variations in ice roughness may induce intense secondary circulations that drive rapid vertical exchange. Enhanced mixing and vertical exchange can entrain heat stored below the mixed layer, increasing basal melting of sea ice within the MIZ. In ice-covered regions, local radiative solar warming leads to direct ablation of sea ice and some bottom melt from the radiation penetrating weakly into the ice-covered upper ocean. Open water regions within and south of the MIZ allow increased radiative upper ocean warming and, through lateral advection, accelerated ice melt. These processes are expected to amplify variance at short spatial and temporal scales across the MIZ. (click image to enlarge)

Summer Ice Retreat and Opening of the Beaufort Sea

SSM/I ice cover for April, June, and August (top, middle, and bottom) for 1990 (left) and 2012 (right). Prior to the recent period of sea ice decline, the MIZ rarely extended beyond the Alaska slope. More recently, the seasonal MIZ develops in July and retreats rapidly northward, leaving large expanses of open water over the Alaska slope and into the deep Beaufort Sea.

Field Program		Observing Array Assets and Configuration
The MIZ intensive field program will employ an array of cutting-edge autonomous platforms to characterize the processes that govern Beaufort Sea MIZ evolution from initial breakup and MIZ formation though the course of the summertime sea ice retreat. The sampling goal is to achieve a deployment of ice-based platforms arrayed around a line that stretches northward approximately 400 km from the Alaska slope (roughly 70°–76°N at 140°W) on 1 July. Ice-based instruments include arrays of Ice Mass Balance and Wave Buoys (IMB/WB), Autonomous Weather Stations (AWS), Ice-Tethered Profilers (ITP), and Autonomous Ocean Flux Buoys (AOFB). An array of drifting and mobile autonomous platforms will operate within the matrix of ice-based instruments. Polar Profiling Floats (PPF) will be deployed at locations spanning the entire line to provide daily profiles of temperature and salinity. Surface Wave Instrument Floats with Tracking (SWIFT) drifters and Waverider Buoys will be deployed in open water, near the MIZ, shortly after its formation, and may be recovered and relocated during the melt season. Two Liquid Robotics Wavegliders will follow the northward sea ice retreat, maintaining position close to the ice-based instruments nearest the ice edge, to provide additional acoustic navigation signals, open water measurements, and boundary layer meteorological measurements within the open water south of the MIZ. Lastly, autonomous Seagliders will follow the retreating ice edge, occupying sections that span open water, the MIZ, and full ice cover to document upper ocean evolution as a function of distance from the ice edge throughout the entire northward retreat. These high-resolution sections will bridge the regions between observations collected by the ice-based and drifting platforms, provide spatial context, and bind the array together.		Idealized (target) configuration of the MIZ DRI observing array. The actual array will deform as it drifts westward through the region. Note the markers indicating various instrument separations (drawing is not to scale). Ice-based instruments will melt out from the south as the MIZ retreats northward. Blue, double-ended arrows mark glider sections that will follow the northward retreat of the sea ice to remain centered on the MIZ. Solid (dashed) light blue lines mark notional positions of the ice edge in June, (July, and August) relative to the observing array. By August, the MIZ is far to the north and much of the ice-based instrumentation has melted out. (click image to enlarge)

Modeling		Sub-array Assets and Configuration
High-resolution modeling of the MIZ in the Chukchi and Beaufort seas will be conducted using three distinctive models targeting various key MIZ processes. The Marginal Ice Zone Modeling and Assimilation System (MIZMAS) model will be used to simulate the evolution of ice thickness and floe size distributions jointly in the MIZ. The MIZMAS model will be used for hindcast, seasonal ensemble forecast, and future projection of the MIZ. The Arctic Cap Nowcast/Forecast System (ACNFS), developed at the NRL, will be used for nowcasts and 5-day forecasts of ice thickness, ice drift, ocean currents, salinity, and temperature fields. The Eddy-resolving Regional Arctic Climate System Model (E-RASM) is a fully coupled model including atmosphere, land hydrology, ocean, and sea ice components. The model will be used to examine the critical physical processes and atmosphere–ocean–ice feedbacks that affect sea ice thickness and area distribution using a combination of forward modeling and state estimation techniques.		Ice-edge and ‘5-dice’ IMB/WB sub-array configuration, depicting oceanographic sampling by floats and gliders beneath the ice and by various ice-based instruments that penetrate through the ice. Gliders conduct sections that extend from full ice cover, through the MIZ, and into open water. Wavegliders and SWIFT drifters sample within the MIZ and the open water to the south. (click image to enlarge)

Ice Mass Balance Buoys, Wave Buoys, and Automated Weather Stations		Autonomous Ocean Flux Buoys		Ice-Tethered Profilers
Wilkinson, Maksym, Hwang, Wadhams, and Doble Autonomous instruments will monitor four parameters continuously: Ice mass balance Open ocean and in-ice wave characteristics Ocean–atmosphere heat flux Floe size distribution Ice mass balance (IMB) + wave buoy (WB) Inference of ice growth or melt at the surface and bottom of the sea ice depends on accurate localization of the ice–ocean interface, which in the case of IMB buoys, relies on measurement of both the ambient temperature and the thermal response of the immediate surroundings of the heater/sensor pairs to short periods of heating, i.e., the temperature elevation above ambient. The thermal response of air, snow, ice, and water to this heating cycle is different, and thus the medium the sensor is embedded in can be recognized. Once the interfaces have been identified the rate of change in the position of the interface along the chain is interpreted as the melt rate. Generally an IMB chain is 5 m long with temperature sensors spaced at 2 cm along its length. This allows a portion of the chain to sample the ambient air, snow, ice, and upper water column temperature. The IMB/WB will be a float, and thus will continue to obtain important data on the evolution of the upper ocean heat and the ocean wave spectra. The background open ocean spectra will be used in conjunction with buoys that are still in the ice to quantify wave attenuation rate. The open water spectra are an important part of the process and therefore Wavegliders should also be deployed in the open water near the ice edge. Automated Weather Station (AWS) AWS installations measure GPS location, wind speed and direction, humidity, air temperature, pressure, solar radiation, and floe rotation. All platforms take advantage of solar power and the two-way communication offered by Iridium. This allows batteries to be recharged and users to alter, when required, the sampling rate remotely. All transmitted data will be piped directly to the Global Telecommunications System (GTS). These data will then be available to numerical weather prediction centers in near-real time. High-resolution satellite imagery will be acquired to obtain co-incident information on the open water fraction and floe size distribution within the area of the buoy arrays and from the ice edge northwards along the buoy deployment line. Analysis of these images will enable us to quantify the continuous evolution of sea ice conditions (open water fraction, floe size distribution, and MIZ width) with respect to the in situ parameters that are measured by the buoys. The principle satellite sensor will be the SAR TanDEM-X (TDX), successor of TerraSAR-X, as it can provide all-weather, high-resolution images (3–18-m pixel size) at reasonable cost.		Stanton and Shaw Autonomous Ocean Flux Buoys will quantify vertical turbulent fluxes from the spring formation of the MIZ through the summertime sea ice retreat. After field installation, AOFBs maintain twice-daily, two-way communications with a computer running at the NPS allowing transmission of the full data timeseries and routine updates of sampling parameters. The buoy system has a hull and floatation system capable of surviving multiple melt-out and refreeze events. The Naval Postgraduate School (NPS) Autonomous Ocean Flux Buoy (AOFB). A surface buoy sits on the ice supporting an instrument package suspended into the upper ocean by a series of poles from the bottom of the surface buoy. The surface buoy contains processing electronics, GPS and Iridium antennae, and batteries. The instrument package is outfitted with a downward looking 300-kHz Acoustic Doppler Current Profiler (ADCP, RDI Workhorse) and a custom-built flux package. Additionally, the buoys have GPS receivers for measuring position and calculating ice velocity. After installation in the field on selected ice floes, AOFBs maintain twice-daily, two-way communications with a computer running at the NPS. (click image to enlarge)		Toole, Krishfield, Timmermans, Cole, and Thwaites An array of four autonomous Ice-Tethered Profilers with velocity (ITP-V) will quantify the seasonally varying upper ocean stratification and velocity field, and the turbulent ice–ocean exchanges of heat and momentum in the Arctic MIZ. The ITP-Vs will sample through the melt season to follow mechanical displacements of the ice as the ice edge sweeps north. The ITP-V array will document the changes in internal wave properties, turbulent fluxes, and entrainment of subsurface heat into the mixed layer as the sea ice concentration evolves during the melt season. Schematic of the WHOI Ice-Tethered Profiler system (left), the profiler with velocity sensor (ITP-V) prior to deployment (upper right), and the surface expression (lower right). (click image to enlarge)

Autonomous Gliders		Polar Profiling Floats		Acoustic Navigation Array and Wavegliders
Lee, Rainville, and Gobat Four Seagliders will repeatedly occupy sections centered on the MIZ, following its northward retreat. Two gliders will occupy short lines (~50 km) designed to resolve short time scale variability about the MIZ itself, while the other two will conduct longer surveys (>150 km) that extend beyond the influence of the MIZ in both the open ocean and ice-covered directions. The Seaglider program is designed to: Collect observations that span open water, the MIZ, and full ice cover Resolve the short temporal and spatial scales associated with key upper ocean processes Quantify how the relative importance of these processes varies as a function of location relative to the MIZ Measure turbulent mixing rates (via micro-temperature) and multi-spectral downwelling irradiance in the upper water column Provide high-resolution spatial context for other components of the DRI The Mobile MIZ Observing Network. Ice-Tethered Profilers, ice-capable Seagliders, and profiling floats, with an acoustic array providing under-ice geolocation and navigation, provide high spatial and/or temporal resolution ocean measurements in the MIZ. The array follows ice drift and retreat though the melt season. Gliders sample from open water, through the MIZ, and into full ice cover, profiling from the ice–ocean interface to 1000 m depth. (click image to enlarge)		Owens and Jayne Twelve WHOI polar profiling floats will be deployed as part of the MIZ observing system. These floats will carry a WHOI micro-modem capable of receiving the signals from the mid-frequency, 780-Hz sound sources that will allow geopositioning during the initial part of the observational period, when the floats profile entirely in ice-covered waters. During the later stages of the experiment, when the region is relatively ice-free, floats will use GPS for positioning. The floats will provide 1-m bin-averaged temperature and salinity profiles from the bottom of the ice or 1 m from the sea surface to 1000 m depth on a daily schedule during the intensive observational period. At the end of the experiment, the floats will change to a 10-day repeat and report their data through the Argo float program.		Freitag An array of at least eight ice-tethered acoustic navigation sources will be deployed in two meridional lines running parallel to the main IMB/WB/ITP array. An additional pair of sources will be carried by two Liquid Robotics Wavegliders. The two Wavegliders will also be instrumented with meteorological sensors to characterize atmospheric forcing over the open water south of the MIZ. The array of sources provides a drifting acoustic navigation network for gliders and floats operating beneath the ice.

Wave and Current Meters
SWIFT Drifters

Thomson

Three instruments will capture the temporal evolution and spatial variation of waves in the MIZ. Two sub-surface moorings equipped with Nortek Acoustic Wave and Current (AWAC) meters will be deployed. Two surface Waverider buoys will be deployed in open water at the southern edge of the MIZ to provide a boundary condition for wave measurements collected by drifters deployed within the MIZ. Six Surface Wave Instrument Float with Tracking (SWIFT) drifters will be deployed into the MIZ as part of ship-supported operations in July, after initial formation and northward retreat of the MIZ.

Specific objectives include:

Observe waves in the evolving MIZ as a function of fetch and season
Evaluate the input–dissipation balance of waves in a mixed fetch of open water and ice floes
Provide wave observations for testing ice–wave models and validating global wave models

(a) Nortek Acoustic Wave and Current (AWAC) and (b) Waverider moorings. Waveriders may also be deployed in a drifting configuration.
(click image to enlarge)

Graduate student researcher Seth Zippel tests SWIFT performance in arctic waters in advance of planned missions during the Marginal Ice Zone experiments in 2014.

Surface Wave Instrument Float with Tracking (SWIFT)

Technical specifications and capabilities of the drifting platform

Remote Sensing

TerraSAR-X images will be acquired as part of the Scottish Association of Marine Science effort.
COSMO SKyMed SAR may be acquired.
The Center for Southeastern Tropical Advanced Remote Sensing will supply remote sensing products, particularly SAR.
NASA IceBridge focused airborne surveys will include measurements of sea ice thickness, surface elevation, and snow cover.
Data will be available from over-flights by the SIZRS (Seasonal Ice Zone Reconnaissance Surveys) project.

Modeling
MIZMAS Zhang, Schweiger, and Steele A new coupled ice–ocean Marginal Ice Zone Modeling and Assimilation System (MIZMAS) will enhance the representation of the unique MIZ processes by incorporating a floe size distribution (FSD) and corresponding model improvements. Scientific objectives include: Examine the historical evolution of the CBSMIZ ice–ocean system and its ice thickness distribution (ITD) and FSD from 1978 to the present to quantify and understand the large-scale changes that have occurred in the system Identify key linkages and interactions among the atmosphere, sea ice, and ocean, to enhance our understanding of mechanisms affecting the Chukchi and Beaufort seas MIZ (CBSMIZ) dynamic and thermodynamic processes Explore the predictability of the seasonal evolution of the MIZ and the summer location of the ice edge in the CBS through seasonal ensemble forecast Explore the impacts of future anthropogenic global climate change (including a summer arctic ice-free regime) on the CBSMIZ processes through downscaling future projection simulations		Arctic Cap Nowcast/Forecast System Posey, Allard, Brozena, and Gardner The NRL has developed a 1/12° Arctic Cap Nowcast/Forecast System (ACNFS). The system is a coupled ice–ocean model and consists of the Los Alamos Community Ice CodE (CICE) and the HYbrid Coordinate Ocean Model (HYCOM) and uses the Navy Coupled Ocean Data Assimilation (NCODA) system. The grid resolution for ACNFS is approximately 3.5 km near the North Pole and 6.5 km near 40°N. ACNFS assimilates satellite measurements (altimeter data, SST, and sea ice concentration) as well as in situ SST and temperature and salinity profiles using a 3DVAR assimilation scheme. Currently, ACNFS assimilates DMSP ice concentration (25-km resolution) along the MIZ. ACNFS produces a nowcast and 5-day forecast each day of ice concentration, ice thickness, ice drift, ocean currents, salinity, and temperature fields.		E-RASM: Eddy-resolving Regional Arctic Climate System Model Maslowski, Roberts, Cassano, and Hughes A fully coupled eddy-resolving regional Arctic climate system model (E-RASM) with an improved ocean–ice–atmosphere boundary layer through data assimilation will be used to address Earth System Model limitations, synthesize the historically available and new expected remotely sensed and in situ data to advance understanding and prediction of arctic sea ice and climate change at hourly to decadal time scales. Three main science objectives are to: Advance understanding and model representation of critical physical processes and feedbacks of importance to sea ice thickness and area distribution using a combination of forward modeling and state estimation techniques Investigate the relation between the upper ocean heat content and sea ice volume change and its potential feedback in amplifying ice melt Upgrade the current version of RASM with data assimilation in WRF/CICE to estimate a physically consistent state of arctic climate for operational and tactical prediction of arctic climate using a single model

Science and Experiment Plan

Marginal Ice Zone (MIZ) Program: Science and Experiment Plan

Lee, C.M., et al., "Marginal Ice Zone (MIZ) Program: Science and Experiment Plan," APL-UW TR 1201, Technical Report, Applied Physics Laboratory, University of Washington, Seattle, October 2012, 48 pp.

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9 Oct 2012

The Marginal Ice Zone (MIZ) intensive field program will employ an array of cutting-edge autonomous platforms to characterize the processes that govern Beaufort Sea MIZ evolution from initial breakup and MIZ formation though the course of the summertime sea ice retreat. Instruments will be deployed on and under the ice prior to initial formation of the MIZ along the Alaska coast, and will continue sampling from open water, across the MIZ, and into full ice cover, as the ice edge retreats northward through the summer. The flexible nature of ice-mounted and mobile, autonomous oceanographic platforms (e.g., gliders and floats) facilitates access to regions of both full ice cover and riskier MIZ regions. This approach exploits the extended endurance of modern autonomous platforms to maintain a persistent presence throughout the entire northward retreat. It also takes advantage of the inherent scalability of these instruments to sample over a broad range of spatial and temporal scales.

MIZ Publications

Wave propagation in the marginal ice zone: Connections and feedback mechanisms within the air–ice–ocean system

Thomson, J., "Wave propagation in the marginal ice zone: Connections and feedback mechanisms within the air–ice–ocean system," Phil. Trans. R. Soc. A., 380, doi:10.1098/rsta.2021.0251, 2022.

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31 Oct 2022

The propagation of ocean surface waves within the marginal ice zone (MIZ) is a defining phenomenon of this dynamic zone. Over decades of study, a variety of methods have been developed to observe and model wave propagation in the MIZ, with a common focus of determining the attenuation of waves with increasing distance into the MIZ. More recently, studies have begun to explore the consequences of wave attenuation and the coupled processes in the air–ice–ocean–land system. Understanding these coupled processes and effects is essential for accurate high-latitude forecasts. As waves attenuate, their momentum and energy are transferred to the sea ice and upper ocean. This may compact or expand the MIZ, depending on the conditions, while simultaneously modulating the wind work on the system. Wave attenuation is also a key process in coastal dynamics, where land–fast ice has historically protected both natural coasts and coastal infrastructure. With observed trends of increasing wave activity and retreating seasonal ice coverage, the propagation of waves within the MIZ is increasingly important to regional and global climate trends.

The evolution of a shallow front in the Arctic marginal ice zone

Brenner, S., L. Rainville, J. Thomson, and C. Lee, "The evolution of a shallow front in the Arctic marginal ice zone," Elem. Sci. Anth., 8, doi:10.1525/elementa.413, 2020.

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4 May 2020

The high degree of heterogeneity in the ice–ocean–atmosphere system in marginal ice zones leads to a complex set of dynamics which control fluxes of heat and buoyancy in the upper ocean. Strong fronts may occur near the ice edge between the warmer waters of the ice-free regions and the cold, fresh waters near and under the ice. This study presents observations of a well-defined density front located along the ice edge in the Beaufort Sea. The evolution of the front over a ~3-day survey period is captured by multiple cross-front sections measured using an underway conductivity–temperature–depth system, with simultaneous measurements of atmospheric forcing. Synthetic aperture radar images bookending this period show that the ice edge itself underwent concurrent evolution. Prior to the survey, the ice edge was compact and well defined while after the survey it was diffuse and filamented with coherent vortical structures. This transformation might be indicative of the development an active ocean eddy field in the upper ocean mixed layer. Over the course of hours, increasing wind stress is correlated with changes to the lateral buoyancy gradient and frontogenesis. Frontal dynamics appear to vary from typical open-ocean fronts (e.g., here the frontogenesis is linked to an "up-front" wind stress). Convective and shear-driven mixing appear to be unable to describe deepening at the heel of the front. While there was no measurable spatial variation in wind speed, we hypothesize that spatial heterogeneity in the total surface stress input, resulting from varying ice conditions across the marginal ice zone, may be a driver of the observed behaviour.

An autonomous approach to observing the seasonal ice zone in the western Arctic

Lee, C.M., J. Thomson, and the Marginal Ice Zone and Arctic Sea State Teams, "An autonomous approach to observing the seasonal ice zone in the western Arctic," Oceanography, 30, 56-68, doi:10.5670/oceanog.2017.222, 2017.

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1 Jun 2017

The Marginal Ice Zone and Arctic Sea State programs examined the processes that govern evolution of the rapidly changing seasonal ice zone in the Beaufort Sea. Autonomous platforms operating from the ice and within the water column collected measurements across the atmosphere-ice-ocean system and provided the persistence to sample continuously through the springtime retreat and autumn advance of sea ice. Autonomous platforms also allowed operational modalities that reduced the field programs’ logistical requirements. Observations indicate that thermodynamics, especially the radiative balances of the ice-albedo feedback, govern the seasonal cycle of sea ice, with the role of surface waves confined to specific events. Continuous sampling from winter into autumn also reveals the imprint of winter ice conditions and fracturing on summertime floe size distribution. These programs demonstrate effective use of integrated systems of autonomous platforms for persistent, multiscale Arctic observing. Networks of autonomous systems are well suited to capturing the vast scales of variability inherent in the Arctic system.

Modeling the seasonal evolution of the Arctic sea ice floe size distribution

Zhang, J., H. Stern, B. Hwang, A. Schweiger, M. Steele, M. Stark, and H.C. Graber, "Modeling the seasonal evolution of the Arctic sea ice floe size distribution," Elem. Sci. Anth., 4, doi:10.12952/journal.elementa.000126, 2016

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13 Sep 2016

To better simulate the seasonal evolution of sea ice in the Arctic, with particular attention to the marginal ice zone, a sea ice model of the distribution of ice thickness, floe size, and enthalpy was implemented into the Pan-arctic IceOcean Modeling and Assimilation System (PIOMAS). Theories on floe size distribution (FSD) and ice thickness distribution (ITD) were coupled in order to explicitly simulate multicategory FSD and ITD distributions simultaneously. The expanded PIOMAS was then used to estimate the seasonal evolution of the Arctic FSD in 2014 when FSD observations are available for model calibration and validation.

Results indicate that the simulated FSD, commonly described equivalently as cumulative floe number distribution (CFND), generally follows a power law across space and time and agrees with the CFND observations derived from TerraSAR-X satellite images. The simulated power-law exponents also correlate with those derived using MODIS images, with a low mean bias of 2%. In the marginal ice zone, the modeled CFND shows a large number of small floes in winter because of stronger winds acting on thin, weak first-year ice in the ice edge region. In mid-spring and summer, the CFND resembles an upper truncated power law, with the largest floes mostly broken into smaller ones; however, the number of small floes is lower than in winter because floes of small sizes or first-year ice are easily melted away. In the ice pack interior there are fewer floes in late fall and winter than in summer because many of the floes are welded together into larger floes in freezing conditions, leading to a relatively flat CFND with low power-law exponents.

The simulated mean floe size averaged over all ice-covered areas shows a clear annual cycle, large in winter and smaller in summer. However, there is no obvious annual cycle of mean floe size averaged over the marginal ice zone. The incorporation of FSD into PIOMAS results in reduced ice thickness, mainly in the marginal ice zone, which improves the simulation of ice extent and yields an earlier ice retreat.

Scaling observations of surface waves in the Beaufort Sea

Smith, M., and J. Thomson, "Scaling observations of surface waves in the Beaufort Sea," Elem. Sci. Anth., 4, 000097, doi:10.12952/journal.elementa.000097, 2016.

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14 Apr 2016

The rapidly changing Arctic sea ice cover affects surface wave growth across all scales. Here, in situ measurements of waves, observed from freely-drifting buoys during the 2014 open water season, are interpreted using open water distances determined from satellite ice products and wind forcing time series measured in situ with the buoys. A significant portion of the wave observations were found to be limited by open water distance (fetch) when the wind duration was sufficient for the conditions to be considered stationary. The scaling of wave energy and frequency with open water distance demonstrated the indirect effects of ice cover on regional wave evolution. Waves in partial ice cover could be similarly categorized as distance-limited by applying the same open water scaling to determine an ‘effective fetch’. The process of local wave generation in ice appeared to be a strong function of the ice concentration, wherein the ice cover severely reduces the effective fetch. The wave field in the Beaufort Sea is thus a function of the sea ice both locally, where wave growth primarily occurs in the open water between floes, and regionally, where the ice edge may provide a more classic fetch limitation. Observations of waves in recent years may be indicative of an emerging trend in the Arctic Ocean, where we will observe increasing wave energy with decreasing sea ice extent.

Air–sea interactions in the marginal ice zone

Zippel, S., and J. Thomson, "Air–sea interactions in the marginal ice zone," Elem. Sci. Anth., 4, 000095, doi:10.12952/journal.elementa.000095, 2016.

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31 Mar 2016

The importance of waves in the Arctic Ocean has increased with the significant retreat of the seasonal sea-ice extent. Here, we use wind, wave, turbulence, and ice measurements to evaluate the response of the ocean surface to a given wind stress within the marginal ice zone, with a focus on the local wind input to waves and subsequent ocean surface turbulence. Observations are from the Beaufort Sea in the summer and early fall of 2014, with fractional ice cover of up to 50%. Observations showed strong damping and scattering of short waves, which, in turn, decreased the wind energy input to waves. Near-surface turbulent dissipation rates were also greatly reduced in partial ice cover. The reductions in waves and turbulence were balanced, suggesting that a wind-wave equilibrium is maintained in the marginal ice zone, though at levels much less than in open water. These results suggest that air-sea interactions are suppressed in the marginal ice zone relative to open ocean conditions at a given wind forcing, and this suppression may act as a feedback mechanism in expanding a persistent marginal ice zone throughout the Arctic.

Wind and wave influences on sea ice floe size and leads in the Beaufort and Chukchi seas during the summer-fall transition 2014

Wang, Y., B. Holt, W.E. Rogers, J. Thomson, and H.H. Shen, "Wind and wave influences on sea ice floe size and leads in the Beaufort and Chukchi seas during the summer-fall transition 2014," J. Geophys. Res., 121, 1502-1525, doi:10.1002/2015JC011349, 2016.

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20 Feb 2016

Sea ice floe size distribution and lead properties in the Beaufort and Chukchi Seas are studied in the summer-fall transition 2014 to examine the impact on the sea ice cover from storms and surface waves. Floe size distributions are analyzed from MEDEA, Landsat8, and RADARSAT-2 imagery, with a resolution span of 1–100 m. Landsat8 imagery is also used to identify the orientation and spacing of leads. The study period centers around three large wave events during August–September 2014 identified by SWIFT buoys and WAVEWATCH III model data. The range of floe sizes from different resolutions provides the overall distribution across a wide range of ice properties and estimated thickness. All cumulative floe size distribution curves show a gradual bending toward shallower slopes for smaller floe sizes. The overall slopes in the cumulative floe size distribution curves from Landsat8 images are lower than, while those from RADARSAT-2 are similar to, previously reported results in the same region and seasonal period. The MEDEA floe size distributions appeared to be sensitive to the passage of storms. Lead orientations, regardless of length, correlate slightly better with the peak wave direction than with the mean wave direction. Their correlation with the geostrophic wind is stronger than with the surface wind. The spacing between shorter leads correlates well with the local incoming surface wavelengths, obtained from the model peak wave frequency. The information derived shows promise for a coordinated multisensor study of storm effects in the Arctic marginal ice zone.

Accuracy of short-term sea ice drift forecasts using a coupled ice-ocean model

Schweiger, A.J., and J. Zhang, "Accuracy of short-term sea ice drift forecasts using a coupled ice-ocean model," J. Geophys. Res., 120, 7827-7841, doi:10.1002/2015JC011273, 2015.

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1 Dec 2015

Arctic sea ice drift forecasts of 6 h – 9 days for the summer of 2014 are generated using the Marginal Ice Zone Modeling and Assimilation System (MIZMAS); the model is driven by 6 h atmospheric forecasts from the Climate Forecast System (CFSv2). Forecast ice drift speed is compared to drifting buoys and other observational platforms. Forecast positions are compared with actual positions 24 h – 8 days since forecast. Forecast results are further compared to those from the forecasts generated using an ice velocity climatology driven by multiyear integrations of the same model. The results are presented in the context of scheduling the acquisition of high-resolution images that need to follow buoys or scientific research platforms. RMS errors for ice speed are on the order of 5 km/d for 24–48 h since forecast using the sea ice model compared with 9 km/d using climatology. Predicted buoy position RMS errors are 6.3 km for 24 h and 14 km for 72 h since forecast. Model biases in ice speed and direction can be reduced by adjusting the air drag coefficient and water turning angle, but the adjustments do not affect verification statistics. This suggests that improved atmospheric forecast forcing may further reduce the forecast errors. The model remains skillful for 8 days. Using the forecast model increases the probability of tracking a target drifting in sea ice with a 10 km x 10 km image from 60 to 95% for a 24 h forecast and from 27 to 73% for a 48 h forecast.

Sea ice floe size distribution in the marginal ice zone: Theory and numerical experiments

Zhang, J., A. Schweiger, M. Steele, and H. Stern, "Sea ice floe size distribution in the marginal ice zone: Theory and numerical experiments," J. Geophys. Res., 120, 3484-3498, do:10.1002/2015JC010770, 2015.

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12 May 2015

To better describe the state of sea ice in the marginal ice zone (MIZ) with floes of varying thicknesses and sizes, both an ice thickness distribution (ITD) and a floe size distribution (FSD) are needed. In this work, we have developed a FSD theory that is coupled to the ITD theory of Thorndike et al. (1975) in order to explicitly simulate the evolution of FSD and ITD jointly. The FSD theory includes a FSD function and a FSD conservation equation in parallel with the ITD equation. The FSD equation takes into account changes in FSD due to ice advection, thermodynamic growth, and lateral melting. It also includes changes in FSD because of mechanical redistribution of floe size due to ice ridging and, particularly, ice fragmentation induced by stochastic ocean surface waves. The floe size redistribution due to ice fragmentation is based on the assumption that wave-induced breakup is a random process such that when an ice floe is broken, floes of any smaller sizes have an equal opportunity to form, without being either favored or excluded. To focus only on the properties of mechanical floe size redistribution, the FSD theory is implemented in a simplified ITD and FSD sea ice model for idealized numerical experiments. Model results show that the simulated cumulative floe number distribution (CFND) follows a power law as observed by satellites and airborne surveys. The simulated values of the exponent of the power law, with varying levels of ice breakups, are also in the range of the observations. It is found that floe size redistribution and the resulting FSD and mean floe size do not depend on how floe size categories are partitioned over a given floe size range. The ability to explicitly simulate multicategory FSD and ITD together may help to incorporate additional model physics, such as FSD-dependent ice mechanics, surface exchange of heat, mass, and momentum, and wave-ice interactions.

Seasonal ice loss in the Beaufort Sea: Toward synchrony and prediction

Steele, M., S. Dickinson, J. Zhang, and R. Lindsay, "Seasonal ice loss in the Beaufort Sea: Toward synchrony and prediction," J. Geophys. Res., 120, 1118-1132, doi:10.1002/2014JC010247, 2015.

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1 Feb 2015

The seasonal evolution of sea ice loss in the Beaufort Sea during 1979–2012 is examined, focusing on differences between eastern and western sectors. Two stages in ice loss are identified: the Day of Opening (DOO) is defined as the spring decrease in ice concentration from its winter maximum below a value of 0.8 areal concentration; the Day of Retreat (DOR) is the summer decrease below 0.15 concentration. We consider three aspects of the subject, i.e., (i) the long-term mean, (ii) long-term linear trends, and (iii) interannual variability. We find that in the mean, DOO occurs earliest in the eastern Beaufort Sea (EBS) owing to easterly winds which act to thin the ice there, relative to the western Beaufort Sea (WBS) where ice has been generally thicker. There is no significant long-term trend in EBS DOO, although WBS DOO is in fact trending toward earlier dates. This means that spatial differences in DOO across the Beaufort Sea have been shrinking over the past 33 years, i.e., these dates are becoming more synchronous, a situation which may impact human and marine mammal activity in the area. Retreat dates are also becoming more synchronous, although with no statistical significance over the studied time period. Finally, we find that in any given year, an increase in monthly mean easterly winds of ~1 m/s during spring is associated with earlier summer DOR of 6–15 days, offering predictive capability with 2–4 months lead time.

Swell and sea in the emerging Arctic Ocean

Thomson, J., and W.E. Rogers, "Swell and sea in the emerging Arctic Ocean," Geophys. Res. Lett., 41, 3136-3140, doi:10.1002/2014GL059983, 2014.

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16 May 2014

Ocean surface waves (sea and swell) are generated by winds blowing over a distance (fetch) for a duration of time. In the Arctic Ocean, fetch varies seasonally from essentially zero in winter to hundreds of kilometers in recent summers. Using in situ observations of waves in the central Beaufort Sea, combined with a numerical wave model and satellite sea ice observations, we show that wave energy scales with fetch throughout the seasonal ice cycle. Furthermore, we show that the increased open water of 2012 allowed waves to develop beyond pure wind seas and evolve into swells. The swells remain tied to the available fetch, however, because fetch is a proxy for the basin size in which the wave evolution occurs. Thus, both sea and swell depend on the open water fetch in the Arctic, because the swell is regionally driven. This suggests that further reductions in seasonal ice cover in the future will result in larger waves, which in turn provide a mechanism to break up sea ice and accelerate ice retreat.

The impact of an intense summer cyclone on 2012 Arctic sea ice retreat

Zhang, J., R. Lindsay, A. Schweiger, and M. Steele, "The impact of an intense summer cyclone on 2012 Arctic sea ice retreat," Geophys. Res. Lett., 40, 720-726, doi:10.1002/grl.50190, 2013.

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25 Jan 2013

This model study examines the impact of an intense early August cyclone on the 2012 record low Arctic sea ice extent. The cyclone passed when Arctic sea ice was thin and the simulated Arctic ice volume had already declined ~40% from the 2007–2011 mean. The thin sea ice pack and the presence of ocean heat in the near surface temperature maximum layer created conditions that made the ice particularly vulnerable to storms. During the storm, ice volume decreased about twice as fast as usual, owing largely to a quadrupling in bottom melt caused by increased upward ocean heat transport. This increased ocean heat flux was due to enhanced mixing in the oceanic boundary layer, driven by strong winds and rapid ice movement. A comparison with a sensitivity simulation driven by reduced wind speeds during the cyclone indicates that cyclone-enhanced bottom melt strongly reduces ice extent for about two weeks, with a declining effect afterwards. The simulated Arctic sea ice extent minimum in 2012 is reduced by the cyclone, but only by 0.15 x 10⁶ km² (4.4%). Thus without the storm, 2012 would still have produced a record minimum.

Seasonal forecasts of Arctic sea ice initialized with observations of ice thickness

Lindsay, R., C. Haas, S. Hendricks, P. Hunkeler, N. Kurtz, J. Paden, B. Panzer, J. Sonntag, J. Yungel, and J. Zhang, "Seasonal forecasts of Arctic sea ice initialized with observations of ice thickness," Geophys. Res. Lett., 39, doi:10.1029/2012GL053576, 2012.

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1 Nov 2012

Seasonal forecasts of the September 2012 Arctic sea ice thickness and extent are conducted starting from 1 June 2012. An ensemble of forecasts is made with a coupled ice-ocean model. For the first time, observations of the ice thickness are used to correct the initial ice thickness distribution to improve the initial conditions. Data from two airborne campaigns are used: NASA Operation IceBridge and SIZONet. The model was advanced through April and May using reanalysis data from 2012 and for June–September it was forced with reanalysis data from the previous seven summers. The ice extent in the corrected runs averaged lower in the Pacific sector and higher in the Atlantic sector compared to control runs with no corrections. The predicted total ice extent is 4.4 ± 0.5 M km², 0.2 M km² less than that made with the control runs but 0.8 M km² higher than the observed September extent.

Recent changes in the dynamic properties of declining Arctic sea ice: A model study

Zhang, J., R. Lindsay, A. Schweiger, and I. Rigor, "Recent changes in the dynamic properties of declining Arctic sea ice: A model study," Geophys. Res. Lett., 39, doi:10.1029/2012GL053545, 2012.

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30 Oct 2012

Results from a numerical model simulation show significant changes in the dynamic properties of Arctic sea ice during 2007–2011 compared to the 1979–2006 mean. These changes are linked to a 33% reduction in sea ice volume, with decreasing ice concentration, mostly in the marginal seas, and decreasing ice thickness over the entire Arctic, particularly in the western Arctic. The decline in ice volume results in a 37% decrease in ice mechanical strength and 31% in internal ice interaction force, which in turn leads to an increase in ice speed (13%) and deformation rates (17%). The increasing ice speed has the tendency to drive more ice out of the Arctic. However, ice volume export is reduced because the rate of decrease in ice thickness is greater than the rate of increase in ice speed, thus retarding the decline of Arctic sea ice volume. Ice deformation increases the most in fall and least in summer. Thus the effect of changes in ice deformation on the ice cover is likely strong in fall and weak in summer. The increase in ice deformation boosts ridged ice production in parts of the central Arctic near the Canadian Archipelago and Greenland in winter and early spring, but the average ridged ice production is reduced because less ice is available for ridging in most of the marginal seas in fall. The overall decrease in ridged ice production contributes to the demise of thicker, older ice. As the ice cover becomes thinner and weaker, ice motion approaches a state of free drift in summer and beyond and is therefore more susceptible to changes in wind forcing. This is likely to make seasonal or shorter-term forecasts of sea ice edge locations more challenging.

References

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Of special interest:

MIZEX Bull. IV (1984). Initial results and analysis from MIZEX 83.
MIZEX Bull. V (1984). MIZEX 84 summer experiment preliminary reports, edited by O.M. Johannessen and D.A. Horn.
MIZEX Bull. VI (1985).

MIZEX-West, edited by P. Wadhams.

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MIZEX-West Study Group, 1983. MIZEX West: Bering Sea marginal ice zone experiment. EOS, Trans. AGU, 64(40), 578–579.

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MIZ Collaboratory on Google Drive

As of 18 August 2015 the Collaboratory is hosted by Google Drive.

WorkSpace		Resources
The MIZ Collaboratory hosted by Google Drive is divided into two sections. The WorkSpace is open for all collaborators to read and write documents, presentations, images, and data. Changes made to files and directories in the WorkSpace will propagate to all copies of the MIZ Collaboratory on Google Drive. This means that if you delete a file in the cloud or in your local copy of the drive, it will disappear from all other copies. Please be considerate when using the Collaboratory. Files will be backed up regularly, but we’d prefer to avoid the labor of restoration.		The Resources directory is open for all collaborators to read and download archived documents, presentations, images, and data. The Resources directory holds relatively stable assets, such as data sets and archived presentations, to make them easily accessible by all collaborators while being protected from accidental deletion. To place material into the Resources directory, upload to the WorkSpace and contact Craig Lee with a request to move the files to Resources.

Getting Started

If you were accessing the Collaboratory hosted by Catalyst with a UWNetID account, continue to use that account to access the MIZ Collaboratory on Google Drive (making sure that you have registered your account with UW Google Apps). Likewise, if you were using a Gmail account to access the Collaboratory on Catalyst, continue to use that Gmail user account to access the MIZ Collaboratory on Google Drive.

UWNetID Users		Gmail Users
For Collaborators with University of Washington UWNetID accounts: Open a private browsing window in your web browser Go to drive.google.com Log in, e.g., uwnetid@uw.edu Enter UWNetID name and password as prompted Go to "Shared with me" Find the MIZ_Collaboratory_WorkSapce and MIZ_Collaboratory_Resources directories		For Collaborators with Gmail accounts: Go to drive.google.com Log in with your Gmail account name and password Go to "Shared with me" Find the MIZ_Collaboratory_WorkSapce and MIZ_Collaboratory_Resources directories

Communications from Scientists & Engineers in the Field
3 August 2014 Enter the ice at ~72°N Continue station work, detouring eastward to skirt a band of heavy ice Plan is to transit eastward along 75°N, through a region of low ice concentration, turning northward at 145°W Move north along 145°W as far as practical, then select a floe for ice camp and cluster 5 deployment Timeline depends on ice conditions, but current estimates put northward turn on Wednesday, 6 August and ice camp start on Thursday, 7 August		2 August 2014 Continue build out and test cluster 5 equipment Occupy stations in Bering Sea, running northeast near the U.S.–Russian border


1 August 2014 Occupy DBO stations Assemble and test instruments and tooling for MIZ cluster 5 NPS hut assembled and placed on main deck Test Seaglider for deployment on Northwind Ridge		31 July 2014 Wave buoy electronics arrive early morning from Anchorage, slung to Araon Depart Nome 12:00 local with all personnel and gear aboard First CTD station at 21:00		30 July 2014 Science party transfers to Araon by helicopter. Most are aboard by noon Wave buoy batteries and provisions sling loaded to Araon in the afternoon


29 July 2014 Transit from Prudhoe Bay to Kaktovik (100 n mi east), through open brash ice Heading for the shelf break tomorrow to deploy two Wavegliders Most MIZ gear ferried to Araon by crab boat		28 July 2014 Returned to Prudhoe Bay, refueled and loaded two Wavegliders Departing tomorrow to look for open water and deploy		27 July 2014 Departed Kaktovik, slow going in a lot of ice Arrived at shelf break in open water, approx. N 70° 55.5', W 144° 31.5', 560 m depth Deployed four Seagliders and two SWIFTs Took several CTD casts and water samples at 5, 25, and 50 m depth Transited back shoreward through a lot of brash ice, and around much larger floes Anchored at Tigvariak Island


26 July 2014 06:00 — departed anchorage at Tigvariak Island 07:00 — passed through Mary Sachs entrance (exit from barrier islands); encountered a lot of ice immediately — passable, but slow going; worked our way eastward along the coast 11:30 — finally cleared sea ice in vicinity of N 70° 17', W 144° 27'; weighed options with 2 hours transit to shelf break plus 3 hours of work once arriving; there is not enough time within the 12-hour limit so we decide to head for Kaktovik anchorage and try tomorrow 14:30 — Anchored at Kaktovik (100 n mi east of Prudhoe) and will get an early start tomorrow for shelf break; there is much less ice this far east so it looks promising to get to deep water for Seaglider and SWIFT deployments		25 July 2014 Load remaining gear, except Wavegliders Mount and test shipboard camera and met package (4.5 m above water) Confirm coms on Seagliders (s/n 196, 197, 198, 199) and SWIFTs (s/n 10, 11); all well and ready to deploy Acquire liquid nitrogen and prep water sampling station Mount Geoforce tracker to Ukpik (should be update on MIZ map) 16:30 (local ADT) begin transit eastward along coast Intent is to get around ice and deploy in vicinity of 71°N, 145°W mid-day tomorrow Iridium open-port mounted, but not yet configured; the next update may be limited to Iridium SMS text		24 July 2014 All personnel arrived Deadhorse All equipment received and accounted for at airport staging facility (Carlile) Cleared BP security and boarded R/V Ukpik Transferred 4 Seagliders, 1 SWIFT, and shipboard met package to Ukpik Began staging on deck Tomorrow: Finish staging this round Begin transit east looking for open/deep water for first round deployment Saturday morning


24 March 2014 Today's activities: The BAS twin otter departed Sachs approximately 0900 L, with 3 aircrew and Jeremy on board. The remaining APL-UW party are booked on the commercial flight from Sachs. We are the last of the MIZ personnel to depart. 23 March 2014 Today's activities: An aircraft fuel problem delayed our departure today, and weather has moved into the camp area so we have suspended flights. Tomorrow is our last day in Sachs Harbour. Tomorrow: Complete packing shipping containers for return to Seattle All BAS personnel (3 aircrew and 1 science party) depart via BAS twin otter All APL-UW personnel depart via scheduled Aklak flight		20 March 2014 Today's activities: Returned all personnel from Camp 3 to Sachs Harbour, BAS party plus bear guard and his dog. Deteriorating weather at camps prevented the planned transfer of personnel from Camp 3 to Camp 2 Weather prevented delivery of replacement LIDAR to NASA at Camp 2 BAS deployments are complete WHOI deployments are complete. All WHOI personnel and one member of BAS party departed Sachs via scheduled flight NASA party remains at Camp 2. They reported poor visibility at Camp 2. They are the last group remaining at camp Helicopter ferried from Camp 3 to Sachs for refueling, and continued on toward Inuvik. Helo ops are complete Tomorrow: Recover camp equipment from Camp 3 Deliver LIDAR equipment to NASA party at Camp 2 A weather front is coming through the camps and Sachs area tonight Once the NASA party completes at Camp 2, work on the ice will be complete and the emphasis turns to demobilization		19 March 2014 Today's activities: Transported 2 BAS wavebuoys to Camp 4 Supplied fuel to Camp 4 NASA planes stopped over in Sachs Harbour to refuel BAS and helicopter worked on instrument deployments at Camp 4 WHOI completed deployments at Camp 4 Tomorrow: WHOI departs Sachs Harbour via scheduled flight BAS should be ready to transfer back to Sachs Harbour by Friday morning


18 March 2014 Today's activities: Transported 3 BAS wavebuoys to Camp 4 Cached fuel at Camp 4 NASA overflights of remote sensing planes Note the camps continue to drift westward and currently lie along approximately longitude 137 W. This increases flight times for support aircraft. NASA group remains at Camp 2 BAS group remains at Camp 3 with the helicopter Tomorrow: WHOI to deploy instruments at Camp 4 BAS completes deployments at Camp 3, and begins work on Camp 4		16 March 2014 Today's activities: NPS suffered iridium modem failure on instrument at camp 3, troubleshot by phone. The modem seemed to work and he elected to spend the night at 3 to verify. NASA moved to Camp 3 for the night, and began work on arrival in the morning. Only one sortie per airplane was possible today. Weather prevented further landings at Camp 3. BAS installed 5 buoys at Camp 1 and 3 buoys (of 5) at Camp 2. The tent was removed from camp 1. In an attempt to reduce beacon latency, the 'moved' reporting distance was decreased, and 'not moved' frequency increased. Anyone watching the miztrack@gmail.com account should expect increased traffic. The beacon was recovered from Camp 1. Camp positions: Camp 1 Lat/Lon: 72.55536,-136.01701 Camp 2 Lat/Lon: 73.49930,-136.19253 Camp 3 Lat/Lon: 74.44022,-136.10528 Camp 4 Lat/Lon: 75.42827,-136.17408 Plan: NPS finish AOFB deployment (Saturday) Helo to ferry from Inuvik to Camp 2 Details of NASA transport to Camp 2 being worked BAS working to deploy buoys around Camp 2 WHOI continues deploying instruments Second C-130 flight with 21,000 l Jet-A due Saturday, mid-day NASA arrives Sachs via charter A/C Sunday		15 March 2014 Today's activities: Cached fuel at Camp 2 BAS installed 3 buoys at Camp 1 NASA group arrived at Sachs Harbour C-130 delivered 21,000 l of Jet-A to airport tanks Plan: APL-UW to finalize living quarters at Camp 3 BAS continues buoy deployment WHOI to deploy instruments


13 and 14 March 2014 Today's activities: APL-UW group completed Camp 2 preps. Camp 2 is now open for business. BAS staged all buoys at Camps 1 and 2. They are ready for helo support to deploy those instruments. Cached fuel at Camps 2 and 3. WHOI installed instruments at Camp 2. The helicopter ferried to Camp 2. BAS moved to Camp 2 and now reside there The bear guard is stationed at Camp 2 with the BAS group APL-UW set a tent at Camp 1. 5 BAS wave buoys are staged there. NPS removed a troublesome anemometer from an instrument at camp 2. Latest camp positions: Camp 1 Lat/Lon: 72.48288,-135.63792 Camp 2 Lat/Lon: 73.43051,-135.70484 Camp 3 Lat/Lon: 74.40180,-135.65768 Camp 4 Lat/Lon: 75.44422,-135.56603 Outlook: NPS finish AOFB deployment (Saturday) Helo to ferry from Inuvik to Camp 2 Details of NASA transport to Camp 2 being worked BAS working to deploy buoys around Camp 2 WHOI continues deploying instruments Second C-130 flight with 21,000 l Jet-A due Saturday, mid-day NASA arrives Sachs via charter A/C Sunday		12 March 2014 Today's activities: The Aklak twin otter flew to Camp 3 with WHOI personnel to deploy instruments. Conditions prevented swapping beacons at Camp 4. Camp 4's beacon came online and began reporting positions The BAS twin flew to Camp 2 with APL-UW personnel to repair the leaky stove High winds prevented replacing the tent, which has fuel in its floor liner due to the leak at Camp 2 Weather limited air operations to one sortie per aircraft. Winds were steady ESE at 20–30 kts and lighting conditions were low-contrast Pilots reported leads opening due to the easterly wind NASA group of 4 arrived in Inuvik, plan to transfer to Sachs on Friday The helicopter continues to hold in Inuvik, ready to ferry to Camp 2, flight time about 2 hours Latest camp positions: Camp 2 Lat/Lon: 73.38361,-135.44769 Camp 3 Lat/Lon: 74.35662,-135.12557 Camp 4 Lat/Lon: 75.42314,-135.34504 Tomorrow's plan: 3 from APL-UW travel to Camp 2 for stove and tent repair WHOI and NPS to Camp 3 for instrument deployment BAS completes instruments prep in Sachs to be ready for deployment, possibly on Friday		11 March 2014 Today's activities: WHOI finished deployments at Camp 2 and began work at Camp 3. ITP 78 deployed at Camp 3. AOFB 32 is partially deployed at Camp 3. Camp 4's location was established, there is a bagged runway, wind sock and beacon. The beacon is not reporting positions. The BAS plane was grounded for the day by a hydraulics leak. Thanks to an epic troubleshooting session by both the BAS and Aklak engineers, the plane is repaired and ready to resume flights tomorrow. BAS prepared their IWB instruments for deployment Outlook: Repair the leaking heater at Camp 2 Cache fuel at Camp 2 WHOI transports gear to Camp 3 NPS completes instrument deployment at Camp 3


9 March 2014 Today's activity: Delivered camp equipment to Camp 3 WHOI installed instruments at Camp 2 NPS installed instruments at Camp 2 The tents are all erected at Camp 2 Tomorrow's plan 3 from APL-UW build tents at Camp 3 via Aklak Twin Otter 1 from APL-UW stays at Sachs to load fuel WHOI and NPS install instruments at Camp 2 and Camp 3 Latest positions: Camp 2: Lat/Lon: 73.36555,-134.98549 Camp 3: Lat/Lon: 74.35664,-135.12557 8 March 2014 Today's activity: The cook tent and 1 of the sleep tents were set up at Camp 2. Heat is on in the cook tent. Camp 2 is now open for business The runway was bagged and the GPS beacon was installed at Camp 3. Position: 74.35668, -135.12568 Three sorties today: the BAS twin ferried Camp 2 gear and WHOI gear to Camp 2. Aklak carried personnel and gear to Camp 2, scouted Camp 3 and bagged the runway for Camp 3. Outlook: WHOI will deploy an ITP, projected 2 flights NPS will deploy the AOFB APL-UW will either work on Camp 2 or Camp 3		6 March 2014 Today's activity: The first scouting flight went out today. A runway with GPS beacon is in place at the Camp 2 site The WHOI party worked on instrument prep The BAS twin is loaded for an early flight to start supplying Camp 2 Outlook Tomorrow we plan to launch the BAS Twin early with gear to establish Camp 2. The Aklak Twin will follow with personnel to set the camp. The second BAS flight is planned to carry WHOI gear to Camp 2 5 March 2014 Today's activity: The third and final air cargo flight arrived by Summit Air Buffalo and was offloaded Our planned scouting flight was scrubbed due to weather The two tents (operations and staging) are furnished, organized, and we are fully open for business The WHOI party, 5 personnel, arrived by commercial flight in the afternoon Geotracker beacon 2 is operating, currently sitting in the operations tent. It will go to the Camp 2 site when we are able to fly our first scouting mission A diagram outlining our personnel and equipment disposition is attached. This is a bit of an experiment, to quickly convey our status. Outlook: We plan to fly our first scouting mission tomorrow to locate a site for Camp 2, weather permitting The WHOI party plans to begin prepping instruments tomorrow Third cargo flight scheduled for tomorrow (6 Mar), no ETA as yet but will likely be in the morning. This will be the last cargo flight. We have engaged the helicopter crew in the flight coordination process with NASA to ensure the remote sensing overflights are uneventful. The helo is staged on Inuvik and we intend to have them stay until camp is ready to accept them. The first scouting flight is tentatively scheduled for tomorrow. Best case we will identify a site for Camp 2 and bag the runway Second Herc flight scheduled for tomorrow (5 Mar) arriving Sachs approx 1100 The third cargo flight is required. The cargo was too bulky to fit in 2 Herc flights. The overflow payload consists mostly (possibly entirely) of wave buoys. We are chartering a Buffalo from Summit Air. The flight is scheduled for Thursday, 6 Mar. Both Twin Otters are scheduled to arrive tomorrow and are scheduled to arrive approx 1630, which should provide ample time to offload the Herc and have it depart. The apron would be very crowded with all 3 planes.		4 March 2014 The APL-UW crew landed in Sachs Harbour and set up operations in the Kuptana lodge. We have limited internet access (only Mike C's computer can't seem to talk to the modem) Iridium phone: designated 1/6 on the phones sheet. (011) 8816 51 481 785 Lodge phone: 867-690-3614 The 3 cargo vans are placed as requested at the airport The arrangement for the airport tents will be finalized once we size up the site To do: Det'on Cho informs us that the third flight will be needed. Sam is looking in to chartering the 1st Air ATR aircraft. This flight could be delayed by a few days if the 1st Air schedule dictates. The first Herc flight is due in today (Tues, 4 Feb) with camp gear. We plan to offload and turn the plane around quickly, establish tents with heat, and begin sorting gear for camps 2 March 2014 The project continues on track to transfer from YK to Sachs today. Work in Yellowknife has gone exceedingly well, due in large part to excellent support from vendors: Det'on Cho, Weaver-Devore, 1st Air, et. al. Yesterday: The final air shipment of small parts arrived at Det'on Cho Martin and Phil (BAS) continue to make progress installing Iridium SIM cards in their buoys Det'on Cho remains confident a 3rd flight will not be needed Continued coordination with NASA for P3 overflight. Sent planning documents to Great Slave Helicopters for review, and to begin incorporating them into the coordination plan. NASA is providing a text-based chat system to communicate with the aircraft. We should be able to monitor the flight and provide input as needed. Upcoming: APL-UW crew transfers to Sachs Harbour 1st Herc flight due in Sachs the day after we arrive. We plan to offload as quickly as possible, establish tents, sort equipment, and make ready to receive the next day's flight of science equipment.