Meet us at Coasts & Ports 2017

Later this week, MetOcean Solutions will be at the 2017 Coasts & Ports Conference in Cairns, Australia. 

Project Director Dr Brett Beamsley and MetOcean Solutions' Australian representative Dr Alexis Berthot will both attend the conference. Brett will be presenting recent research on dredging plume dispersion.  

Running from 21 to 23 June, the Coasts & Ports Conference is the pre-eminent forum in the Australasian region for professionals to meet and discuss multi-disciplinary issues related to coasts and ports. This year the conference theme is 'Working with Nature', reflecting the need to design and operate projects from a perspective that places the natural environment at the forefront.

Geraldton Port - improving long wave predictions with real-time wave buoy data

“MetOcean Solutions has worked exceptionally hard to assist the Port of Geraldton with its surge problem. The product they now deliver is heavily relied on when scheduling shipping. The efficiencies gained in reduced labour costs to port users are significant, but is the contribution to safety that represents the greatest gain. In 2005 there were 242 parted ships lines at Geraldton. Following the developments in forecasting Long Wave effects at Geraldton, last year there were only 30 parted ships lines. This was the lowest number of parted lines since records have been kept. MetOcean Solutions is keeping Geraldton Port efficient, and port workers safe.”
Captain Ross Halsall, Acting Harbour Master, Port of Geraldton.

Observational wave data can help ports manage the onset of long wave events. In recent work for Geraldton Port (Australia), we improved our harbour long wave forecasts by integrating wave buoy data from two upstream locations into the short-range predictions.

Long (or infragravity) waves are created when swell waves interact with the coast and result in water level oscillations with periods much longer than the original swell waves. Long wave periods of 60-120 seconds are typical, and these are very problematic because their wavelength is similar to the size of ships. When such waves enter a harbour the moored vessels are energised, causing dangerous surging which can break lines and put personnel in danger. As a result, ports often have to close when long wave heights exceed a safe threshold.
 
Accurate forecasts of long wave height can help ports increase safety, reduce unwarranted closures and effectively plan for reopening. For the past 11 years, MetOcean Solutions has provided a specialist long wave forecasting service that ports and harbours throughout New Zealand and Australia have come to rely upon.   
 

Numerical simulation showing that the sea-swell climate in the vicinity of the Port of Geraldton is extremely complex, mainly due to the reef near the Port entrance.

Numerical simulation showing that the sea-swell climate in the vicinity of the Port of Geraldton is extremely complex, mainly due to the reef near the Port entrance.

“Our scientific research over many years provides the basis for a robust prediction system,” explains Senior Oceanographer Dr Severin Thiebaut. “We use a semi-empirical technique to establish the relationship between the offshore wave spectra and the long wave height at each berth in a port. It's a method that we have tested at more than 30 locations worldwide”. 
 
The forecast wave spectra is derived from the suite of global and regional numerical models run by MetOcean Solutions. Geraldton Port have been using these predictions to guide the harbour operations since 2007. Predictions have proved very reliable, but sometimes the arrival of a swell front may differ from the forecast by a few hours as the exact timing is difficult to resolve perfectly with a spectral wave model. To supplement the long wave forecasts, we developed a new technique using real-time wave buoy data to improve the short term predictions and better detect occasions with a sharp rise in long wave energy inside the harbour. 
 
‘“The goal is to ensure that our port clients are never surprised by weather events,” says Dr Thiebaut.  

The Department of Transport maintains wave buoys at Rottnest Island and at Jurien Bay, some 370 km and 170 km to the south of Geraldton, respectively. The live data from these buoys, updated at 30 minute intervals, are used to track the progression of swell up the west coast of Australia and provide harbour long wave predictions some 5-6 hours ahead.

Data from wave buoys at Rottnest Island and Jurien Bay help improve long wave predictions for Geraldton Port.

Data from wave buoys at Rottnest Island and Jurien Bay help improve long wave predictions for Geraldton Port.

“Using the live buoy data provides additional confidence to the standard forecasts. In particular, it allows us to accurately capture any rapidly rising long wave events. It also gives the port operators a better idea of when wave heights will decrease to safe working levels. Geraldton Port accesses the forecast information through the web-based MetOceanView platform and through their local environmental monitoring software. On the same plot we show the measured long waves at the berth along with the values that are forecast by our standard system plus those predicted by the buoys.” 
 

Comparison between measured and predicted significant long wave heights (Hslpw) in the Port of Geraldton in 2012 based on Jurien Bay real-time wave buoy data.

Comparison between measured and predicted significant long wave heights (Hslpw) in the Port of Geraldton in 2012 based on Jurien Bay real-time wave buoy data.

Contact us for a discussion of what we can do to help your port. Call +64 6 758 5035, email enquiries@metocean.co.nz or visit www.metoceanview.com.
 

SurfZoneView part of Defence Force training exercise

MetOcean Solutions joined the Defence Technology Agency (DTA) in a training exercise in Army Bay, Whangaparoa during May. As part of a larger trial involving the New Zealand Navy and Air Force, DTA were testing a wave buoy and integrating the data into the SurfZoneView beach landing software.

The field phase of Exercise Joint Waka was held at Army Bay and the inner Hauraki Gulf from 14-19 May 2017. It involved New Zealand Army vehicles, amphibious sealift vessel HMNZS CANTERBURY, and Royal New Zealand Air Force NH90 medium utility helicopters. The exercise sought to enhance the New Zealand Defence Force’s ability to deploy offshore to deal with any contingencies including humanitarian crisis, natural disasters and instability within our region.

Figure 1: HMNZS Canterbury

Figure 2: Amphibious vessel used for the landing exercise.

Developed in a collaboration between DTA and MetOcean Solutions, SurfZoneView allows the visualisation of beach landing conditions. Moving people and equipment from sea to land is one of the most complex tasks completed by the New Zealand Defence Force. Such operations are necessary when port facilities are not available, for example when providing natural disaster relief in New Zealand and the Pacific. The safety and success of shore landings are largely dependent on surf zone conditions, and SurfZoneView uses hydrodynamic modelling to provide a rapid and accurate assessment of the waves and currents at any location. Clear, easy-to-use maps of the nearshore conditions are displayed along with tools to assist with operational decision making.

Figure 3: Dr Jamie Halla (left) and Theo Zlatanov (right) from DTA and Dr Rafael Guedes from MetOcean Solutions (centre) getting ready for the trial on the Canterbury ship.

Senior Oceanographer Dr Rafael Guedes was involved with the trial. “It is very hard to assess the beach conditions when you are out at sea. Wave breaking patterns and surf zone currents can change drastically over only a few tens of metres as they are influenced by local bathymetry. By the time a vessel is close enough to the shore to allow operators to judge conditions, it is often already impacted by the waves. SurfZoneView allows operators to visualise the conditions over a stretch of coastline, to help them decide where the best landing place is that day, or sometime in the near future.

Figure 4: It is very hard to assess nearshore conditions from sea.

“The surf zone conditions vary from day to day depending on wind direction, swell characteristics and general circulation. To model the surf zone, the software needs input data describing offshore conditions. These data can either come from forecasts or from real-time measurements such as those from a wave buoy.

Figure 5: Screenshot from MetOceanView showing the forecast site at the location where the New Zealand Defence Force wavebuoy was deployed.

“In this training exercise, we used both. DTA deployed a wave buoy to provide real-time conditions, and we also set up a high resolution forecast site for the location. We can set up a forecast site within an hour, rapidly making available reliable wind, wave and current predictions. The buoy data provides an accurate description of the local conditions, and the forecast allows us to predict how these conditions will change over time.

“During the training exercise, a local storm developed. Waves near the landing site rose to over 1.5 m in just a few hours, with wave periods progressively increasing and directions shifting from north-east to northerly. The development was tracked on SurfZoneView, allowing us to predict conditions around the shore landing site, and how these would change over time as the storm progressed.”

See the example maps of the maximum wave height predicted by SurfZoneView in Figure 7, during the events marked by the black vertical lines in Figure 6. Information from the model is automatically processed to define safety thresholds including whether it is safe to attempt landing on the shore. These thresholds can then form part of the information assessed by operational staff when making a go / no-go decision.

Figure 6: Forecast provided by MetOcean Solutions during the period of the exercise, showing significant wave height  (Hs) and peak wave period  (Tp). Black vertical lines show the events along the development of the storm chosen as input conditions for SurfZoneView. Significant wave height, Hs, is the average height (in metres) of the largest one-third waves. It approximately corresponds to the height of waves as estimated by a trained observer at sea. Peak wave period (Tp) is the wave period (in seconds) of the most energetic waves in a sea state.

Figure 7: As the storm progresses, landing conditions worsen. Example output for the two events highlighted in Figure 6, showing maximum wave height increasing around the landing location. Coloured line along the shoreline displays safety thresholds for the landing vessel. 

“Models are most accurate when we use the best possible input data," adds Rafael. "Wave buoys provide site-specific, accurate data very quickly. Using such buoys alongside SurfZoneView allows the New Zealand Defence Force to go to any location, deploy a buoy and within less than an hour access accurate data to help them land personnel and supplies safely. To aid operation planning, MetOcean Solutions can set up a site-specific forecast for anywhere in the world. This means that we can quickly generate a forecast for wherever SurfZoneView needs to be used, thereby providing the best possible support for the Defence Force and other users.

“We are grateful to be invited to participate in this training exercise. Testing it under real conditions provides important information on where the tool adds value operationally. Coincidentally, we also assisted the Italian Littoral Warfare Unit with similar tests in Sardinia during May, and gained valuable feedback. ”

Figure 8: Based on chart depth, wave height, tide level and wave setup, SurfZoneView displays safe water levels for vessels approaching the shore. Left: map displaying safety thresholds. Right transect (indicated on map) profiles for (top): maximum wave height, including cross-hatched area for breaking waves; and (bottom): water depth and corresponding safety thresholds.

SurfZoneView was developed in close collaboration with DTA, and several overseas navies have indicated interest in purchasing the software.

Nearshore renewable wave energy assessment in Mexico

In July 2016, the international wave power company Eco Wave Power commissioned MetOcean Solutions to provide wave statistics for a nearshore site in Cuyutlan, Manzanillo, on the west coast of Mexico.  

Figure 1: Model depths (top) and snapshot of modelled significant wave height (bottom) for a 0.05 degree SWAN domain for 01 January 2006. Extensions of child nests are shown by the black rectangles. Mean wave direction is shown by the arrows..

Figure 1: Model depths (top) and snapshot of modelled significant wave height (bottom) for a 0.05 degree SWAN domain for 01 January 2006. Extensions of child nests are shown by the black rectangles. Mean wave direction is shown by the arrows..

“Our company required wave statistics to assess whether it was feasible to install a wave power plant at the location”, says Eco Wave Power project manager Guillermo Sherwell. “An overview of the wave conditions is essential for the planning of offshore installations - it allows us to assess operability and identify potential hazards. The data also helps document important environmental conditions that may require further attention.”  

Dr Séverin Thiébaut from MetOcean Solutions was in charge of the project, while Dr Rafael Guedes led the wave model implementations. 

“We set up a multi-nest wave hindcast model to replicate the wave climate at the nearshore site,” explains Séverin. “We modelled the 2005-2014 period so that we could reproduce the ambient wave climate and reliably estimate the most extreme wave conditions that can occur in a 30-year period."

In consultation with the client, the team picked three nearshore sites representative of the proposed location of the wave power plant in water depths of 4, 6 and 8 m. Annual, seasonal and monthly wave analyses were carried out for these sites to extract ambient and extreme wave statistics to assess the design, workability and efficiency of the proposed wave power plant. . 

The Simulating WAves Nearshore (SWAN) model was used for the work. A 4-level nesting approach was applied to downscale wave spectra from a global model to the shallow nearshore locations of interest. Wind fields for the model were derived from the Climate Forecast System Reanalysis (CFSR), and tidal constituents from the Oregon State University Tidal Inverse Solution (OTIS). The site is prone to tropical cyclones, and a cyclone mask was used to remove tropical cyclone signatures from the hindcast metocean data.

The model outputs were used to calculate wave power, the rate at which energy is being transmitted. Fatigue analysis was assessed by estimating the total number of individual waves of varying height and period.

Figure 2: Density plot of the total significant wave height (Hs) vs the peak wave period (Tp) at one of the sites. The plot provides a visual representation of the total number of 3-hourly hindcast data (10 years) per Hs-Tp bin, normalised by the bin sizes to obtain a unit of m/s.

Figure 2: Density plot of the total significant wave height (Hs) vs the peak wave period (Tp) at one of the sites. The plot provides a visual representation of the total number of 3-hourly hindcast data (10 years) per Hs-Tp bin, normalised by the bin sizes to obtain a unit of m/s.

“We produced regional summary maps of the conditions,” explains Séverin. “These showed the spatial distribution of variables such as mean significant wave height for the total, swell and sea components, mean peak wave period, mean wave direction and wavelength.” (Illustrated in Figure 1). Joint probability occurrences of variables such as significant wave height and peak period were also included (as illustrated in Figure 2).

Figure 3: Annual wind rose plot for one of the sites. Sectors indicate the direction from which the wind is coming.

Figure 3: Annual wind rose plot for one of the sites. Sectors indicate the direction from which the wind is coming.

Wind statistics were also generated, including monthly and annual wind speed exceedance probabilities, joint probabilities of wind speed and direction and corresponding wind roses (illustrated in Figure 3). 

“Values such as the 99th percentile non-exceedance significant wave height (Hs) level is often used to assess the wave climate and structure design for energetic events. This denotes the significant wave height which is not exceeded for 99% of the time.” states Séverin. “Similarly useful are extreme metocean statistics like the return period values for wind and wave, i.e. the likely maximum that can occur within a specific extended duration.”

“We are very happy with the quality of the work,” states Guillermo Sherwell from Eco Wave Power. 
 

Monster wave measured by Southern Ocean Wave Buoy

Earlier today, MetOcean Solutions' wave buoy in the Southern Ocean recorded a whopping 19.4 m wave.

Senior Oceanographer Dr Tom Durrant is thrilled. "This is one of the largest waves recorded in the Southern Hemisphere," he explains. "This is the world's southern-most wave buoy moored in the open ocean, and we are excited to put it to the test in large seas."

Persistent westerly winds and unlimited fetch combine to make Southern Ocean waves among the biggest in the world. Sub-Antarctic waters are difficult to work in, and reliable wave data for the area is scarce. The buoy was deployed in a collaboration between the New Zealand Defence Force and MetOcean Solutions aiming to get valuable observations from this remote part of the ocean. Such observations will enable better forecasting and design of vessels built to withstand Southern Ocean conditions. Moored in a water depth of 150 m, the buoy is located within the New Zealand Exclusive Economic Zone, 11 km south of Campbell Island. 

"The buoy is performing extremely well so far," adds Tom. "Not only is it surviving these large waves, but it is making detailed recordings of extreme sea states in the Southern Ocean, a region rarely observed by in-situ instruments. During the depths of winter, Southern Ocean waves are enormous, with significant wave heights averaging over 5 m, and regularly exceeding 10 m. Individual waves can double that size. Accurate measurements of these conditions will help us understand waves and air-sea interactions in these extreme conditions. This, in turn, will lead to improvements in the models used to simulate the waves, providing better forecasts, both for the Southern Ocean and for the wider region. Waves generated in the Southern Ocean have far-reaching effects, contributing significantly to the wave climate in all the major ocean basins."

The Southern Ocean Wave Buoy data are freely available from MetOcean Solutions. View the data here or contact us by emailing enquiries@metocean.co.nz.

SurfZoneView finalist for KiwiNet Award

SurfZoneView was used by NZDF to support beach landings on a recent mission in Fiji.

SurfZoneView was used by NZDF to support beach landings on a recent mission in Fiji.

The New Zealand Defence Technology Agency (DTA) and MetOcean Solutions are finalists for the 2017 KiwiNet Research Commercialisation Award. The award is for the SurfZoneView tool, which was developed by MetOcean Solutions in partnership with the Defence Technology Agency (DTA) to support beach landing operations conducted by the New Zealand Defence Force (NZDF). The DTA is the main provider of research, science and technology support to the NZDF and the Ministry of Defence.

The KiwiNet award is New Zealand’s premier event celebrating the organisations and individuals that turn scientific discoveries into innovative products and services that will grow the New Zealand economy.

SurfZoneView is one of three finalists in the running in the MinterEllisonRuddWatts Research & Business Partnership category.

SurfZoneView is a tactical decision aid to support beach landings. Moving people and equipment from sea to land is one of the most complex tasks completed by the New Zealand Defence Force (NZDF). Amphibious operations are required when port facilities are not available, most commonly when supporting our neighbours in the Pacific or New Zealanders at home after natural disasters such as Cyclone Winston and the Kaikoura earthquakes. The safety and success of amphibious landings are largely dependent on surf conditions.

In humanitarian and disaster relief, safe and efficient transfer of people and equipment is required. SurfZoneView is a fast, reliable and simple software tool that can be used by command teams to plan and execute safe and efficient amphibious and nearshore operations. Based on hydrodynamic modelling, SurfZoneView allows a rapid assessment of the waves and currents at any coastal location. Clear, easy-to-use maps of the nearshore conditions are displayed, and tools are provided to assist with operational decision making.

In 2016, SurfZoneView won the Ministry of Defence Industry Awards of Excellence in the category 'Provision of a product to Defence for less than $15 million'. 

KiwiNet (the Kiwi Innovation Network) is New Zealand’s network of public research organisations, working together to transform scientific discoveries into marketable products and services.

The winners of the award 2017 KiwiNet Awards will be announced on 13th July 2017.

Read more about the nomination on the KiwiNet website.

Vacancy: Oceanographic Modeller

MetOcean Solutions is a science-based consultancy and forecast supplier that provides specialist numerical modelling and analytical solutions in meteorology and oceanography. With offices based in Raglan and New Plymouth, New Zealand, our international team works on world-wide projects and data analysis. We passionately believe in applying the latest information technologies to data services and remaining grounded in rigorous scientific methods.

A medium-sized company, MetOcean Solutions occupies several niche consultancy and service roles and has a rapidly growing forecast and hindcast sector. We are currently seeking a talented oceanographic modeller to join our science team.

Employees of MetOcean Solutions enjoy an open-office, upbeat culture within a coastal village environment on the North Island of New Zealand. Our company atmosphere promotes a “work hard - play hard”’ attitude, supported by flexible hours to ensure a healthy work-life balance. We encourage our people to bring fresh ideas to the table, rise to any challenge, and remain passionate about our products and the company mission.

We are seeking a self-starter to work in our multi-disciplinary R&D environment. Your role will be to contribute to the wave modelling team across the areas of research,  operational forecasting, hindcasting, and consultancy.  You will be supported by other expert modellers and developers in our team.

This is a fantastic opportunity to work in a growing environment with an interesting and challenging mix of science and technology.

Qualifications: PhD or equivalent experience.

In order to apply you must have the following skills and experience:

  • Expert knowledge of WAVEWATCH III and/or SWAN.
  • Experience analysing and critically assessing oceanographic model data.
  • Scientific code development skills in Python and Fortran.
  • Experience working with, and organising, large geophysical datasets.
  • Experience working on a Linux platform.
  • Strong technical and scientific report  writing skills  in English, with the ability to communicate complex science to a range of audiences.

The following would be beneficial, but are not essential:

  • Experience  running long term model hindcasts.
  • Involvement in an operational forecasting environment.
  • Wave model code development.
  • Experience interacting with databases.
  • Working in a remote High Performance Compute environment.

Our ideal candidate would demonstrate the following characteristics:

  • Integrity and high standards.
  • High level of attention to detail.
  • Effective decision-making skills.
  • Methodical and logical approach to .problem solving
  • Enjoys being part of a team that moves quickly.
  • A quick learner with a “can do” attitude.
  • An ability to prioritise tasks and manage projects in a timely fashion.
  • A supportive and positive attitude.
  • A curious mind that will encourage exploration.  

Please note before you apply: This role is a permanent full-time position, but hours can be flexible to suit your lifestyle. Pay is based on skill and experience. The job position is in our Raglan Office, New Zealand. Applications close on June 15, 2017.

To apply for this position, please email your cover letter and CV to: t.eytan@metocean.co.nz

The Moana Project - an atmosphere-ocean knowledge infrastructure for New Zealand

Expert oceanographers from New Zealand leading marine science organisations have joined forces in a proposal to improve our understanding of New Zealand ocean dynamics and the coastal zone. 

The proposal, detailed on the Moana Project website, was submitted to the Ministry of Business, Innovation and Employment's (MBIE's) Endeavour Fund in March this year. 

Details of the Moana Project are provided on www.moanaproject.org

Details of the Moana Project are provided on www.moanaproject.org

"New Zealand has one of the world’s largest oceans," says Prof Moninya Roughan, MetOcean Solutions' Chief Scientist who coordinated the proposal. "Our ocean provides vital social, cultural, economic and environmental benefits. To safeguard these benefits for future generations we need to understand how our ocean works. This understanding will help good management of our oceans in a future of global climate change."

The project brings together a team of leading oceanographers from New Zealand's top science organisations, who will work with international experts in the field. 

Science organisations involved include MetOcean Solutions, the Cawthron Institute, NIWA, and Auckland, Waikato, Otago and Massey Universities. The team will collaborate with international experts from Australia and the US. In addition, the Moana Project has support from a wide range of ocean-information end-users, including the New Zealand Defence Technology Agency, the fishing industry, New Zealand Aquaculture, the Ministry for Primary Industries and Waikato Regional Council.  

Dr Peter McComb will present an outline of the project at the New Zealand Marine Science Conference in Christchurch in July. 

MBIE is expected to make a decision on the funding in August 2017. 

News related to the project will be published on the Moana Project website

Peter McComb in Southern Ocean seminar at Valparaiso University, Chile

MetOcean Solutions is visiting Chile this week. 

As part of the visit, Managing Director Dr Peter McComb will give a seminar on Friday 5 May at Valparaiso University. The seminar will detail the Southern Ocean wave project, a collaboration between the New Zealand Defence Technology Agency and MetOcean Solutions. As part of the project, MetOcean Solutions helped deploy the world's southernmost moored wave buoy in February 2017.

Dr McComb is excited to share the Southern Ocean project with colleagues in Chile. 

"Southern Ocean waves are famously enormous. Created by persistent westerly winds and a large fetch of uninterrupted ocean, these waves present serious obstacles for any vessels operating in the area. Understanding the dynamics of the Southern Ocean can help us forecast wave conditions, which is important for any nation located close to the Antarctic. 

"As a world first, New Zealand has installed an open ocean wave buoy in the Southern Ocean which can measure the huge waves and provide essential data to help us understand the area. Data collected will be used to improve our models, enabling us create more reliable wave forecasts for the region. We are keen to share data with our Chilean colleagues to ensure that the world science community benefits as much as possible from the project."

The full abstract of the talk is provided below.

An improved wave spectral characterisation of the Southern Ocean
Tom Durrant*, Peter McComb* and Sally Garrett^

The Southern Ocean is the southernmost part of the global ocean and represents around 22% of the world's sea surface area. The combination of persistent westerly winds and the largely unbroken expanse of sea produces potentially enormous fetches, resulting in the Southern Ocean experiencing higher wave heights for longer periods than any other body of water. Due to the harsh ocean environment and remote location, it is also the least observed of any ocean body. While satellite altimeter data can be used to estimate the surface variance, the wave spectral characteristics cannot be measured remotely, and consequently the directional wave spectra Southern Ocean are poorly sampled and not well understood. Here, we present a project that aims to provide a quantitative assessment of the performance of recently implemented improvements of source term physics in WAVEWATCH III in the Southern Ocean, including an analysis of the relative importance of large scale ocean currents. A moored wave buoy at 53 degrees South is an important part of the project scope, and the deployment of this equipment and the data obtained since February 2017 will be presented and discussed.

*MetOcean Solutions. ^ New Zealand Defence Technology Agency

Check out the Southern Ocean wave buoy direct data feed.

Read the New Zealand Herald news article on the project.

Click here for further information about the buoy.  

University of New South Wales and CSIRO visit MetOcean Solutions

This week, MetOcean Solutions is hosting a workshop for researchers from the University of New South Wales (Australia) Coastal and Regional Oceanography Team and the Australian Commonwealth Scientific and Industrial Research Organisation (CSIRO). 

"The workshop will gather experts in physical oceanography from the three organisations as well as students, postdocs and early career scientists," explains Prof Moninya Roughan, the Chief Scientist at MetOcean Solutions. "It will be a great opportunity for us to exchange knowledge and establish collaborations on upcoming initiatives."  

The workshop, which runs from 24-28 April, includes a number of sessions dedicated to scientific writing as well as a series of short research seminars. Themes include meso-scale ocean circulation and oceanic eddies, as well as operational oceanography.

MetOceanView - making the offshore oil & gas industry safer and more efficient

Worldwide, a variety of offshore oil and gas companies use historical data from MetOceanView to understand the environment they work in. Packaged up in the site’s ‘hindcast app’, historical wind, wave and current data is summarised in an easy-to-access format that users can download and integrate into their operational planning.

“The offshore oil and gas industry needs access to reliable site data,” explains Senior Oceanographer Dr Rafael Guedes. “Nowadays, many data sources are available, and the industry needs a robust web platform where they can easily access, browse and download time-series from some of the best hindcast data sources available around the globe. To meet their needs, we set up a hindcast downloading app within our MetOceanView web service.”

Reliable data

The hindcast app provides access to an extensive compilation of data, going as far back as 1958 for some of the datasets.

“We host some of the most reliable global ocean and atmospheric reanalysis data sources in the world,” adds Dr Guedes. “These include NOAA’s CFSR V1 and V2, Hycom from the National Ocean Partnership Program (NOPP) and JRA-55 from the Japanese Meteorological Agency (JMA). In addition, we also provide MetOcean Solutions’ in-house WAVEWATCH III wave hindcast datasets.”

Gaining efficiency

Dealing with huge datasets is not easy, and to set up a useable service, practical obstacles had to be overcome.

“One common problem when accessing historical data is that the volume of data in gridded datasets can be very large,” says Dr Guedes. “For example, a subset of the HYCOM dataset we host comprises about 2.6 trillion individual data points for each variable. Reading long-term time-series from such enormous datasets can be very slow. To make a user-friendly service, we came up with an efficient process to speed up the reading, so that datasets that used to take more than two hours to download could be read in just five minutes.”

One-stop-shop for ocean data

The service works by hosting a range of reference datasets in our servers, giving the client access to unlimited data from all available global datasets as well as MetOcean Solutions’ wave and current model outputs.

“We provide a user-friendly map-based web interface where the user can inspect the different data sources and request time-series for any available grid location,” adds Dr Guedes. “The results are generated without human intervention and delivered within minutes in standard file formats, a link to which is sent directly to the user’s email.”

Data for safer operations

The hindcast app gives access to historical ocean temperature, current, elevation and wave data, as well as atmospheric parameters such as wind, temperature and precipitation.

“Accurate wave, wind and current information is essential for anyone operating offshore,” explains Dr Guedes. “Oil and gas companies use the hindcast data for a range of purposes, including determining the potential operational conditions for offshore locations and ensuring safety at sea.”

The hindcast data subscription service allows customers to browse map views of global datasets with descriptions of the variables that can be downloaded. Grid points show the exact location of each data point. Time-series are provided in either CF-compliant netCDF files or a format specially requested by the client. Wave hindcast data can be downloaded as time-series of spectral parameters or as two-dimensional, frequency-direction wave spectra. This allows a comprehensive description of the modelled wave field over the entire globe. For example, the spectra shed light on the multiple wave systems influencing wave conditions at a certain location and given time.

Making our clients’ life easier

This is the second year of delivering online historical metocean data services to Shell.  “We’ve found the global hindcast portal very valuable,” states Octavio Sequeiros, Shell Metocean Engineer. “Previously, to obtain data for a given location we had to create a specific purchase order for each request. Now, unlimited high quality historical data for any location are just a mouse-click away.

“The fast data download has made our planning easier, more efficient and cost-effective” continues Mr. Sequeiros. “The app is easy to use, and because it provides map layers along with the data grid locations, we can inspect areas and do a few queries before we decide to download time-series. Many summary statistics are shown in tile format, which means we can get a sense of the data before committing to downloads. We mostly use the time-series of wave parameters and wave spectra. On these, we run our own statistics in-house to obtain operational and design criteria for preliminary studies of new potential sites for oil and gas exploration. Our goal is to get workability predictions using accurate modelling.”

High level statistics from each of the datasets hosted by MetOcean Solutions is available via our MetOceanView interface.

Sea surface temperature snapshot from CFS dataset.

Sea surface temperature snapshot from CFS dataset.

Sea ice area snapshot from CFS dataset.

Sea ice area snapshot from CFS dataset.

Eastward wind snapshot from CFS dataset.

Eastward wind snapshot from CFS dataset.

Sea surface wave significant height snapshot from MetOcean Solutions’ dataset.

Sea surface wave significant height snapshot from MetOcean Solutions’ dataset.

Alexis Berthot representing MetOcean Solutions in Australia

We are very pleased to welcome Dr. Alexis Berthot, who will be representing MetOcean Solutions in Australia. Based in Sydney, Alexis's main focus will be looking after the company's Australian clients and providing solutions tailored to the local environment and requirements. 

Alexis’s academic and professional background is in physical oceanography and coastal science. Following an MSc in Marine Environmental Sciences from the University of Marseille, France, he completed a PhD in Physical Oceanography at the University of Western Australia. He has worked in coastal and ocean research and engineering consulting for over 15 years, as a principal numerical modeller, technical lead or project director. 

From his involvement with a wide range of coastal and maritime engineering projects, Alexis has gained extensive experience in hydrodynamic, wave, sediment transport and water quality modelling. 

“I have followed the development of Metocean Solutions since the company started," explains Alexis. "I have been continuously impressed by the high technical quality of the work, the innovative tools developed, and the team's enthusiastic approach when tackling new challenges. I am very excited to join the company and assist in making sure that all Australian companies and government agencies get the opportunity to have Metocean Solutions' great technical expertise and forward thinking solutions at their fingertips.” 

Alexis can be reached at a.berthot@metocean.co.nz or by calling +61 422 369 314.

Sea surges as ex-cyclone Debbie moves through

Heavy rains and surging seas plagued New Zealand as the remnants of cyclone Debbie moved  across the country this week.

“Storm surges occurred in different places across New Zealand as the storm moved through,” explains Senior Oceanographer Dr Rafael Soutelino. “We were lucky that the system moved through fast and did not coincide with large tides, otherwise the coastal flooding could have been a lot worse.”

Storm surges occur when the sea rises as a result of wind and atmospheric pressure changes associated with a storm. The surges build up over time and will worsen when a low pressure system lingers. 

“MetOcean Solutions forecast storm surges nationwide using a complex high definition 3D hydrodynamical model,” continues Rafael. “The model computes the atmospheric effects on coastal water levels. It combines this with baseline water levels generated by open ocean eddies and water column expansions and contractions caused by the spatially-variable vertical density distribution.

“Our modelling shows that as the storm progressed, it caused storm surges in different parts of the country. Although mostly mild, the storm surges were still high enough to cause coastal flooding in sensitive areas. 

The storm progresses: wind and rain (right) and storm surges (left) coincide as ex-cyclone Debbie passes over New Zealand.  

The storm progresses: wind and rain (right) and storm surges (left) coincide as ex-cyclone Debbie passes over New Zealand.
 

Storm surges up to 35 cm high occurred in a number of coastal locations around New Zealand.  

Storm surges up to 35 cm high occurred in a number of coastal locations around New Zealand.
 

“We were very lucky that the storm moved through so fast, and that it coincided with neap tides. Had it happened at spring tides, when the high tide levels are higher, flooding in the area could have been much worse. Our models show that at spring tide, the storm surge would have been high enough to almost match the measured river level after all the rain. In that scenario, the river would not have drained into the ocean as fast, which means the flooding would have been worse and lasted longer.”

Coastal flooding could have been much worse had the storm surge coincided with spring high tide at the Whanganui River mouth.

Coastal flooding could have been much worse had the storm surge coincided with spring high tide at the Whanganui River mouth.

Storm surge forecasts provide valuable information for for low-lying coastal locations, and these solutions are readily available to public authorities. 

“MetOcean Solutions’ New Zealand storm surge model has a resolution of 5 km. It’s the only operational hydrodynamical model for the country and we’ve been running it for more than five years now. During that time we have used it for oil spill and search and rescue modelling, and during the Rena disaster is provided essential guidance for the national response activities. We developed a similar model for the south coast of Australia, which has been operational for more than one year. This model is used by our Alliance partners OMC International in their specialist under keel clearance applications. 

“We run these types of models all over the world,” says Rafael - even in his home country of Brazil where the complex flows along the continental shelf are important to the offshore oil field operations.   

For further information about storm surge warnings and the New Zealand 3D hydrodynamical model, please contact us at enquiries@metocean.co.nz
 

Two million data points a day, and counting

Every day, the MetOceanView service ingests and serves up to our clients more than 2 million unique data points. These are modelled and observed data providing vital marine weather information to users.

The MetOceanView platform displays forecast and historical data for a range of locations. Clients worldwide use the site to access the results from customised wave and hydrodynamic models, helping them make important decisions to maximise safety and improve efficiency.   

“MetOceanView provides a phenomenal amount of information for a wide range of clients,” explains Andre Lobato, who works on data management for MetOceanView. “In order to run such a system, the platform has to process an enormous amount of data.”

Model and observational data are ingested into MetOceanView to provide a complete picture of ocean weather conditions for our clients.

Model and observational data are ingested into MetOceanView to provide a complete picture of ocean weather conditions for our clients.

“Every day, we ingest about 2.25 million discrete data points. More than 2 million of these are unique rows of modelled data from global weather and marine models. In addition to modelled data, we continuously incorporate satellite, lightning, weather station, wave buoy, current meter and tide gauge data as part of the operational infrastructure behind MetOceanView. Some of these data, like METAR stations, NOAA-NDBC buoys, NOAA-MADIS, Himawari 8, GOES and MODIS satellite images are displayed directly on the MetOceanView interface. Others are shown to provide comparisons with our modelled data - e.g. wave buoy data displayed on a graph comparing observed to forecasted wave height.

“Real-time lightning data at times add a huge number of additional observations. Provided through Blitzen (TOA and GPATS), each single lightning strike constitutes a discrete observation. This means that on some days we incorporate millions of lightning data points per day, displaying real-time strikes for Australia, New Zealand and Europe.

Example of one-hour real-time lightning observations for Wednesday 29 March as shown in MetOceanView. Red dots represent clusters of lightning strikes.

Example of one-hour real-time lightning observations for Wednesday 29 March as shown in MetOceanView. Red dots represent clusters of lightning strikes.

We also use observational data to calibrate and validate our meteorological, wave and hydrodynamic forecast models. Observed data can also be used to directly improve our near-real-time forecasts, and can result in significant accuracy gains.

“All this information comes from a variety of sources. Much of the data used in MetOceanView are from our own models and instruments, but some observational data come from external providers. Some of it is private, for example where clients have observations that can help improve the models for their locations.  

“Ingesting such quantities of data requires a range of techniques. Often we have to process the raw information coming in to make it useable for our internal databases. We have designed our systems so that they can handle any data format.

“Ultimately, our clients use MetOceanView as a one-stop-shop for their marine weather information needs. The data we incorporate are valuable to our clients because they help them gain the complete picture of the atmospheric and marine conditions at their site. Good data visualised in an easy-to-understand format allows informed decision-making, which makes for safer operations and increased efficiency, and that is what MetOceanView is all about.”

For more information about MetOceanView, watch our introduction video here, see www.metoceanview.com or email enquiries@metocean.co.nz
 

Kaikoura wave model data now available

Hindcast wave model data are now available for the Kaikoura region. The data, which includes two high-resolution nested domains around the Kaikoura Peninsula and Clarence (regions where active coastal construction is taking place) were generated by dynamically downscaling waves from MetOcean Solutions’ global wave model using a series of Simulating WAves Nearshore (SWAN) model nests. 

Snapshot of significant wave height (Hs) and peak wave directions for the SWAN domains defined for Kaikoura. Inserts show the Clarence (right) and Kaikoura Peninsula (bottom) nests.   

Snapshot of significant wave height (Hs) and peak wave directions for the SWAN domains defined for Kaikoura. Inserts show the Clarence (right) and Kaikoura Peninsula (bottom) nests. 
 

“We prioritised the model runs to ensure that suitable time-series and boundary data are available for the Kaikoura rebuild effort,” explains Project Manager Dr Brett Beamsley. “The model domains are representative of the pre-earthquake bathymetry, but we don’t expect wave characteristics at depths exceeding ~30m to be significantly different between before the earthquake and now, because depth changes in deeper water are not expected to significantly influence wave propagation.” 

“Much of the rail and SH1 roading network north of of Kaikoura historically went very close to the sea and as a result were often closed due to waves washing over the narrow foreshore. Design tolerances for reconstruction of these networks will require an understanding of the likely impacts of large waves, including storm return periods and maximum expected wave heights. In the absence of measured data, this understanding can only be achieved through long period hindcasts.

“Additionally, these hindcast datasets can be used for boundary conditions for specific high-resolution wave models employed to understand implications of the new harbour (which is expected to be completed by mid year) or breakwaters, including wave energy penetration, overtopping and infragravity waves.”

For further information on the data available, please contact b.beamsley@metocean.co.nz

More heavy weather on the horizon

A low pressure system over the Tasman Sea brought strong winds and heavy downpours to New Zealand's North Island last night, resulting in widespread flooding in east Auckland and the Coromandel. 
 
The New Zealand MetService issued a severe weather warning this morning, predicting continued heavy rainfall and risk of flash flooding for large parts of the northern North Island. 
 
Unfortunately the long range forecast shows more to come. Another intense Tasman Sea low pressure system is currently predicted to develop and bring severe weather to central New Zealand early next week, as the image from MetOceanView shows. 

View to the weather: gale force winds forecast for early next week. Image from MetOceanView.com

View to the weather: gale force winds forecast for early next week. Image from MetOceanView.com

For severe weather warnings, see the New Zealand MetService website http://www.metservice.com/warnings/severe-weather-warnings.

MetOceanView can be found at www.metoceanview.com

An operational oceanographic forecast / hindcast model for Shanghai, China

MetOcean Solutions recently completed the development of operational high-resolution wave and hydrodynamic models for the Yangtze River mouth and coastal areas off Shanghai. 

The work combined cutting-edge science within our agile operating system to set up wave and current models for Hangzhou Bay, a region within the East China Sea which is partially enclosed by the Ryukyu chain of islands. 

“It is a very tricky area to model,” notes Senior Oceanographer Dr Rafael Guedes. “The region is characterised by a wide, shallow and highly irregular shelf with many small islands and underwater reefs. Accurate bathymetry for the area is limited. The site is strongly influenced by the phenomenal seasonal discharge from the Yangtze River, which is one of the largest rivers in the world, and is also subject to strong tidal currents.” 

 Bathymetry of the East China Sea. Red dots show the locations of measured data used to validate the models.

 Bathymetry of the East China Sea. Red dots show the locations of measured data used to validate the models.

 
Progressive downscaling of outputs from MetOcean Solutions’ global wave model WAVEWATCH III using two SWAN nests. 

Progressive downscaling of outputs from MetOcean Solutions’ global wave model WAVEWATCH III using two SWAN nests. 

Snapshot of surface salinity from the ROMS model. Blue denotes low salinities; red high.

Snapshot of surface salinity from the ROMS model. Blue denotes low salinities; red high.

“In order to model the location well, we had to capture the meteorological events occurring within the East China Sea as well as the swell generated beyond the Ryukyu Islands which propagates into the bay. Frequent typhoons ravage the area, and these are always hard to resolve well. All in all, the area displays a challenging combination of highly variable bathymetry, strong temperature and salinity differences and complex mixing processes.”

The SWAN (Simulating WAves Nearshore) model was used to resolve the wave climate and the Regional Ocean Modeling System (ROMS) was applied to simulate the circulation. 

“To model the area we used a technique known as ‘dynamical downscaling’,” explains Rafael. “This process uses information from large scale global models to drive regional models at much higher resolution. The technique allows us to resolve fine-scale features near the coast while still accounting for remote influences to the area from long-generated swell or meso-scale currents.”

Quantile-quantile plot comparing measured and modelled significant wave height (Hs) for wave hindcast using (black) existing CFSR wind fields and (red) adjusted wind fields to correct for observed wind bias.

Quantile-quantile plot comparing measured and modelled significant wave height (Hs) for wave hindcast using (black) existing CFSR wind fields and (red) adjusted wind fields to correct for observed wind bias.

“High-quality input data sources are critical to running wave and hydrodynamic models in such complex settings,” continues Rafael. “We found persistent wind speed bias near the bay in the global reanalysis data source that we used to calibrate the high resolution models. Correcting this bias before running the wave model significantly improved model results just offshore of the bay as shown in the comparison of measured and modelled significant wave height.

The area has heavy shipping traffic, and the operational system outputs, including 7-day forecasts of site-specific waves, winds and currents, are now available to marine users. Please contact us and we will connect you with our partner agency in China.

Live Southern Ocean wave buoy direct data feed

MetOcean Solutions is now hosting the direct data feed from the Southern Ocean wave buoy on our website, at www.metocean.co.nz/wave-buoy.

The direct data feed is live at www.metocean.co.nz/wave-buoy.

The direct data feed is live at www.metocean.co.nz/wave-buoy.

The instrument, which is the southernmost moored open ocean wave buoy in the world, was deployed on February 8, 2017 as part of a collaborative project between the New Zealand Defence Force and MetOcean Solutions. 

"We are pleased to say that everything seems to be working according to plan," says Dr Peter McComb who was present at the deployment. "The buoy is located 11 km south of Campbell Island, a location infamous for its harsh conditions. On average, the island gets less than an hour of sunshine 215 days out of 365, and winds of more than 100 km per hour occur at least 100 days a year. The buoy is moored in a water depth of 150 m and is fully exposed to the predominantly westerly wave systems generated by the relentless procession of mid-latitude storms." 

Southern Ocean important for climate

Senior Oceanographer Dr Tom Durrant is excited to be getting data from the Southern Ocean. "The Southern Ocean is known to play an important role in the Earth's climate system, cycling heat, carbon and nutrients,” he states. “Waves modify the air-sea fluxes and the mixed water masses are then redistributed by the Antarctic Circumpolar Current, creating a complex interacting system. Persistent mid-latitude storms combined with a lack of landmasses create large fetches and strong winds, ideal conditions for generating large waves. 

"The waves generated in this region have far reaching effects, contributing significantly to the wave climate in all the major ocean basins. The New Zealand west coast, for example, is periodically battered by large swell systems generated in Southern Ocean storms. 

The buoy was launched on 8 February 2017.

The buoy was launched on 8 February 2017.

Data will help ocean science

"Despite the importance of the region, there are almost no in situ observations in the Southern Ocean. Currently, there is no published wave spectra data from any location south of 47 S to the ice edge (at ~63 S in summer months). Remote altimeter observations provide a valuable source of significant wave height, and have been used to great effect in the Southern Ocean, but these do not provide spectral information which allows us to explore the details of the extreme sea states. The data from this deployment will fill a valuable gap in our understanding of waves in the region and provide a much needed ground truth for validating the global wave models. In recognition of this value, the data will be made freely available to the scientific community." 
 

Persistent polar activity keeps the cold weather coming

Upper atmosphere temperatures remain influenced by colder polar air masses, shown in blue.  Image based on GFS data.

Upper atmosphere temperatures remain influenced by colder polar air masses, shown in blue.  Image based on GFS data.

If you live on the west coast of New Zealand and feel that the 2016-17 summer has been worse than average you'd be right.

"Since winter 2016, New Zealand has been subjected to persistent polar activity," states Tim Gunn, MetOcean Solutions' weather ambassador. "This results in south-westerly fronts hitting our coastlines, one after the other, bringing with them rain and colder than average temperatures.”

The westerly winds result in upwelling along north-facing coastlines.

The westerly winds result in upwelling along north-facing coastlines.

Polar troughing, which results in westerly wind patterns, is typically replaced by mid latitude synoptic weather systems by mid to late November. These normally bring with them warmer, sunnier and more stable weather. However, this year the change hasn't occurred yet.  

The ocean has been affected too. 

Colder than average temperatures are not stopping enthusiastic bathers in Taranaki.

Colder than average temperatures are not stopping enthusiastic bathers in Taranaki.

"The sea is colder than normal for this time of year in some locations," says Dr Rafael Soutelino, MetOcean Solutions' forecast manager. "On the west coast, the strong pattern of westerly winds which is unusual for this time of year has enhanced upwelling of cooler waters along predominantly north-facing coastlines such as North Taranaki and Bay of Plenty. As a result, those places are experiencing colder than average sea surface temperatures," he explains.