Summary of Working Paper No. 68-1996
I.4.1: Content of Database
By V. Vasilyev, L. Tsoy, Y. Glebko and L.Timofeeva, Central Marine Research
and Design Institute (CNIIMF), St.Petersburg, Russia; and S. Brestkin, A.
Buzuyev, Y. Gorbunov, S. Nikolayev, V. Porubayev, K. Teitelbaum and S. Frolov, Arctic
and Antarctic Research Institute (AARI), St.Petersburg, Russia
In parallel with expansion of the electronic catalogue, work on maintenance of
it's database at up-to date level is conducted. During 1996 more than 70 chart
updatings were done. About 40 charts were issued for the first time, other
updatings were done due to occurrence of new cartographical materials and
corrections, published in Notices to Mariners (about 20).
The major part of the new charts are the coastal charts and plans of straits,
harbours and northern ports (scales 1:25,000 - 1: 5,000 - about 20). As an
example the chart Admiralty number 19455 for Pevek port with the scale 1: 10,000
with "A" sub-plan addendum "Oil pier moorings 1:1,000" - notices to mariners, 40
week issue can be represented.
The work on the catalogue was started for INSROP purposes but we plan to
continue to update the catalogue independently of INSROP financing, because it is of
value only in up-to-date state.
Examination of data available at the AARI, assessment of their volume and
quality have shown that the AARI has sufficient information for addressing the
goals of the Program. However, only a small portion of the work necessary for
arranging this information, can be fulfilled within the framework of the Project.
Under these conditions it was considered advisable to focus on supplementing
and adapting the databases available at the AARI and to develop a technology for
their use which will allow the probability of favourable and unfavourable
conditions of navigation along the Northern Sea Route to be estimated in the first
approximation.
It is shown in the Report that an assessment of the probability of various
types of navigation conditions can be made based on the available databases within
the WMO framework. The obtained probability estimates should be corrected
taking into account information on discontinuities in the ice cover and
atmospheric, which is contained in the databases of observations from ships of
opportunity.
The following work was performed:
An approach to employing climatic (review) databases in estimating the
probability of encountering ice of different thickness along the ship motion route was
developed. It is shown that this objective can be achieved on the basis of the
regression analysis and classification of ice thickness distribution depending
on navigation difficulty.
Technology for taking into account the generalized characteristics of
discontinuities in the ice cover when selecting the routes for an escort of ships by
icebreakers was evolved. The regions of the probable use of discontinuities along
the route for navigation on anomalous early dates were identified. Modal
orientation, the specific length, distribution of orientation and distribution of
the length of discontinuities were calculated in grid points. It is shown in what
way these data can be used for addressing the goals of INSROP. The results of
calculating the generalized characteristics of discontinuities in April-June
for the Laptev Sea were transferred to the INSROP Secretariat in the form of
ASCII files.
Technology for the probabilistic assessment of the degree of ice pressures
along the NSR based on multiyear data on atmospheric pressure was developed. A
computer-based Handbook was prepared and transferred to the INSROP Secretariat. It
allows estimates of the probability of varying ice pressures in the NSR region
with a temporal resolution of one 10-day period and a spatial resolution of
200 km. The Handbook presents a set of the files with a total volume of 6 Mbytes.