CL 13/2020

IHO File No. S3/3075 CIRCULAR LETTER 13/2020 11 March 2020 REPORT ON THE 7TH SESSION OF THE IMO SUB-COMMITTEE ON NAVIGATION, COMMUNICATIONS AND SEARCH AND RESCUE (NCSR 7) References: A. IHO CL 14/2019 dated 4 March - Report on the 6th Session of the IMO Sub-Committee on Navigation, Communications, and Search and Rescue; B. IHO CL 62/2019 dated 10 December - Preparation for the 7th Session of the IMO Sub-Committee on Navigation, Communications, and Search and Rescue (NCSR). Dear Hydrographer, 1. As announced in Reference A, the 7th session of the Sub-Committee on Navigation, Communications and Search and Rescue (NCSR 7) of the International Maritime Organization (IMO) was held at the IMO Headquarters in London, United Kingdom, from 15 to 24 January 2020. The IHO was represented by Secretary-General Dr Mathias Jonas, Director Abri Kampfer and Mr Peter Doherty, the Chair of the World-Wide Navigational Warning Service Sub-Committee (WWNWS-SC). The following NAVAREA Coordinators were also represented: Canada (XVII & XVIII), France (II), Japan (XI), New Zealand (XIV), Norway (XIX), Spain (III) United Kingdom (I) and United States (IV & XII). 2. As indicated in Reference B, the agenda for NCSR 7 included the following items of interest to IHO Member States: Agenda Item 3: Routeing measures and mandatory ship reporting systems; Agenda Item 8: Consideration of descriptions of Maritime Services in the context of e-navigation; Agenda Item 9: Updating of the GMDSS master plan and guidelines on Maritime Safety Information (MSI); Agenda Item 10: Safety measures for non-SOLAS ships operating in polar waters; Agenda Item 11: Revision of SOLAS chapters III and IV for Modernization of the GMDSS, including related and consequential amendments to other existing instruments; Agenda Item 12: Response to matters related to the radiocommunication ITU-R study group and ITU World Radiocommunication Conference; Agenda Item 14: Developments in GMDSS satellite services and Agenda Item 22: Any other Business. 3. The relevant discussions, considerations and decisions / recommendations are summarized in Annex A. All meeting documents and the full report of NCSR 7 (NCSR 7/23) will be available on the IMODOCS website (https://webaccounts.imo.org/) when issued. Dates for NCSR 8 4. The 8th session of the NCSR (NCSR 8) is currently scheduled to be held at the IMO Headquarters from 10 to 19 February 2021. Actions required from the IHO and its Member States 5. The IHO Secretariat will ensure that the relevant subsidiary organs and subordinate bodies of the IHO are informed of the outcomes of NCSR 7 and invite them to consider how it affects their activities and work plan and develop inputs to the relevant agenda items as appropriate. This action concerns primarily the Hydrographic Services and Standards Committee (HSSC) and its working groups, and the WWNWS-SC. 6. In particular IHO Member States are requested to support the Secretariat´s submission in Annex B to the 102nd session of the Maritime Safety Committee (MSC 102) in support of the inclusion of the revision of MSC 232(82) - The Revised Performance Standards for Electronic Chart Display and Information Systems (ECDIS) - into the agenda for NCSR 8. This is a necessary step in support of the S-100 Roadmap and achieving the operational introduction of S-101 ENCs, the deadline for submissions is 24 March 2020. 7. IHO Member States, in particular those with NAVAREA Coordinator responsibilities, are requested to submit proposals to the MSC 102 on the cost implications, including additional resources needed, related to the dissemination of MSI over multiple recognized mobile satellite services, with particular emphasis on potential cost-sharing formula. 8. Hydrographic Offices are requested to consider their NCSR and Maritime Safety Committee (MSC) pre-meeting preparations and engagement with their national maritime administrations when formulating national positions on relevant agenda items, taking into account discussions in the applicable IHO subordinate bodies to ensure a consistent approach is maintained. 9. Hydrographic Offices are encouraged, in general, to maintain liaison with their national Maritime Administration to ensure that their views and interests are acknowledged in their country’s views on, and contribution to, the progress of outputs affecting the provision of hydrographic services and maritime safety information. This is particularly relevant for those agenda items covering aspects of the GMDSS and the display of navigational information on various bridge equipment, for which IHO Member States have a direct interest and expertise. On behalf of the Secretary-General Yours sincerely, Abri Kampfer Director Annex: A. Summary of the Discussions at NCSR 7 (English only) B. IHO Submission to MSC 102 (English only) IHO File No. S3/3075 Annex A to IHO CL 13/2020 Summary of the Discussions at NCSR 7 Agenda Item 3 - Routeing measures and mandatory ship reporting systems 1. The Sub-Committee considered the proposal submitted in document NCSR 7/3/1 (Norway), regarding the draft amendments to the existing traffic separation schemes and associated routeing measures in Norway – "Off the western coast of Norway", "Off the coast of southern Norway" and "Off the coast of Norway from Vardø to Røst". After consideration, the Sub-Committee agreed with the modified proposal on the draft amendments to the existing traffic separation schemes and associated routeing measures, with a view to adoption by the Committee. 2. The Sub-Committee considered the proposal submitted in document NCSR 7/3/2 (Poland), regarding the draft amendments to the existing traffic separation scheme and associated measures, "Slupska Bank", Poland, aiming at establishing a third section of TSS, and adjusting and renaming the existing east part, in order to reduce the danger of groundings in the area of shallows detected further east of the existing TSS in and outside the Polish territorial seas, in the southern part of the Baltic Sea. After consideration, the Sub-Committee agreed with the proposal on the draft amendments to the existing "Slupska Bank" traffic separation scheme and associated measures, with a view to adoption by the Committee. 3. The Sub-Committee considered the proposal submitted in document NCSR 7/3/3 (France), regarding a draft amendment to the conditions of use of the two-way route in the "Off Ushant" traffic separation scheme, which was proposed in order to remove ambiguities and take into account technological developments. After consideration, the Sub-Committee agreed with the proposal on the draft amendments to the "Off Ushant" traffic separation scheme, with a view to adoption by the Committee. 4. The Sub-Committee considered the proposal in document NCSR 7/3 (Australia), containing the draft amendments to the existing two-way route in the Great Barrier Reef and Torres Strait. After consideration, the Sub-Committee agreed with the proposal on the draft amendments to the two-way route in the Great Barrier Reef and Torres, with a view to adoption by the Committee. 5. The provisions agreed by the Sub-Committee will now be submitted to the MSC for adoption at its 102nd session in May 2020. Implementation of the provisions mentioned will be six months after adoption by the MSC. 6. The Sub-Committee agreed to recommend to the Committee that the following existing adopted measures be revoked, with the adoption of the above-mentioned draft amendments, due to their complete replacement by new measures: .1 "Off the coast of Norway from Vardø to Røst”, set out in paragraph 1.1 of COLREG.2/Circ.58, with its associated annex 1 to the circular; .2 "Off the western coast of Norway" and "Off the southern coast of Norway", set out in paragraphs 1.1 and 1.2 of COLREG.2/Circ.62, with their associated annexes 1 and 2 to the circular, respectively; and  .3 "Slupska Bank", set out in paragraph 1.2 of COLREG.2/Circ.61, with its associated annex 2 to the circular. Agenda Item 8 - Consideration of descriptions of Maritime Services in the context of e- navigation 7. The Sub-Committee considered document NCSR 7/8, with the view to provide additional guidance for further development of Maritime Services (MS) descriptions (MSC.1/Circ.1610), including technical services and product specifications, to guide the work being undertaken by domain coordinating bodies according to resolution MSC.467(101). 8. The Sub-Committee agreed that in order to progress the harmonized development of Maritime Services descriptions further, overarching coordination meetings for sharing experiences and reporting progress within the relevant domain coordinating bodies should continue. Furthermore, noting the target completion year for the current output being 2021, the Sub-Committee observed that it might need to be extended. 9. The Sub-Committee considered the need for arrangements to progress the work on further development of the descriptions of Maritime Services intersessionally, as well as the need for the organization of related workshops or symposia. After discussions, the Sub- Committee was of the view that an IMO intersessional harmonization group, with a scope which could include some inputs from the Facilitation Committee (FAL), could effectively enable the Organization leading the work to progress the development of descriptions of Maritime Services. The IMO Secretariat advised to wait on further maintenance or revision of MS descriptions until it had been clarified how the process would be established and progressed. 10. The Sub-Committee considered the need for a revision of MSC.1/Circ.1595 on E- navigation strategy implementation plan – Update 1, reflecting latest developments and future tasks. Recognizing that there was no dedicated output enabling the consideration of the SIP update at the next session, the Sub-Committee agreed that interested parties should be invited to progress the work intersessionally and present a mature draft to a future session of the Sub- Committee under agenda item ʺAny other businessʺ, to complete the update. 11. The Sub-Committee noted that Singapore had developed a video to promote better understanding of Maritime Services in the context of e-navigation that was informally presented outside the meeting and was available on social media and YouTube https://www.youtube.com/watch?v=WenDzWY-tXc. Agenda Item 9 - Updating of the GMDSS master plan and guidelines on Maritime Safety Information (MSI) 12. The Sub-Committee noted information provided by the Secretariat on the new GISIS module on Shore based facilities for the Global Maritime Distress and Safety System (GMDSS) Master Plan, which was released in February 2019 (GMDSS.1/Circ.23 refers), and encouraged Member States to review the information available in the GMDSS module of GISIS and update it as soon as changes occurred. 13. The Sub-Committee considered the proposal by the IHO WWNWS Sub-Committee and the WMO-IOC JCOMM WWMIWS Committee (NCSR 7/9) to: .1 amend the International SafetyNET Manual (MSC.1/Circ.1364/Rev.1, as amended by MSC.1/Circ.1364/Rev.1/Corr.1), consolidating a guidance on technical  requirements for Fleet Safety which was disseminated, on an interim basis, by means of MSC.1/Circ.1611, and amending also the title of the Manual to reflect the consolidation; and .2 approve a new MSC circular containing the terms of reference of the IMO Enhanced Group Call Coordinating Panel extracted from the Manual. 14. The Sub-Committee agreed to the draft revision of MSC.1/Circ.1364/Rev.1 on International SafetyNET Services Manual and to the draft MSC circular on the IMO Enhanced Group Call Coordinating Panel; and to forward them to the Committee for approval. 15. The Sub-Committee agreed to the proposal to modify the GMDSS Master Plan in GISIS to make information available on the operational status of new recognized mobile satellite services for dissemination of MSI (i.e. planned/testing/operational) in each NAVAREA/METAREA. In this context, the Sub-Committee: .1 invited Member States to report to the IMO Secretariat on the progress and status of implementation of newly recognized mobile satellite services by MSI providers; and. .2 requested the Secretariat to modify the GMDSS Master Plan in GISIS to make information available on the operational status of new recognized mobile satellite services for dissemination of MSI and, until the GMDSS Master Plan in GISIS was modified, to circulate any information received regarding the implementation of new recognized GMDSS mobile satellite services by means of an appropriate GMDSS circular. 16. The Sub-Committee considered the cost implications, including additional resources needed, related to the dissemination of MSI over multiple recognized mobile satellite services. 17. Concerns were expressed, in particular, on the potential escalation of costs for MSI providers, the risk of a potential reduction of MSI messages disseminated to ships, the impact on the future recognition of new GMDSS services and, most importantly, on the safety of ships and the sustainable development of shipping. The Sub-Committee also expressed the view indicating the urgent need for IMO to liaise with relevant international organizations, with the involvement of Member States, in order to: .1 develop appropriate solutions to address cost-related issues for the dissemination of MSI over multiple recognized mobile satellite services; and .2 consider the establishment of a cost-sharing formula to alleviate the cost burden put on Member States responsible for the dissemination of MSI in different NAVAREAS and METAREAS due to the recognition of new mobile satellite services for the GMDSS. 18. After consideration and recognizing that this was mainly a policy issue, the Sub- Committee agreed to refer the matter to the Committee for consideration and invited interested Member States and international organizations to submit proposals to the Committee, as appropriate. Agenda Item 10 - Safety measures for non-SOLAS ships operating in polar waters 19. The Sub-Committee considered whether and to what extent requirements should be applied to non-SOLAS ships operating in polar waters. The Sub-Committee also emphasized the importance of any new chapters of the Polar Code being written to make it clear that they apply to non-SOLAS ships undertaking international voyages that include polar waters, and expressing that a transition period should only be considered on a provision by provision basis and for a minimal number of provisions. 20. The Sub-Committee, noting the overwhelming support during deliberations in plenary to the importance to enhance safety of non-SOLAS ships in polar waters, and noting the need to progress the work intersssionally, agreed the establishment of a correspondence group, under the coordination of New Zealand. The contact details for the coordinator are: Ms. Beryl Matete PO Box 25620, Wellington, 6140, New Zealand Tel: + 64 4 473 0111 Email: [email protected] Agenda Item 11 - Revision of SOLAS chapters III and IV for Modernization of the GMDSS, including related and consequential amendments to other existing instruments 21. The Sub-Committee considered proposals related to definitions in regulation IV/2 and, after consideration, agreed: .1 to the proposed amendments to the draft definitions of "General radiocommunications" (regulation IV/2.1.8) and "Enhanced Group Call (EGC)" (new definition); .2 that the current definition of "International NAVTEX service" (regulation IV/2.1.7) was no longer required and should be deleted based on the decision taken regarding the proposed amendments to regulation IV/7.1.4 and that, for the same reason, no additional definitions for "NAVTEX" or "National NAVTEX service" were required; and .3 that no additional definitions for "distress alert" and "operational communications" were required. 22. The Sub-Committee also agreed to the IHO proposal made at 15th meeting of the Joint IMO/ITU Experts Group on Maritime Radiocommunication Matters, that the WWNWS-SC when reviewing the NAVTEX Manual in future, would consider the need to review the existing text with respect to SAR information, in order to articulate the current operational procedures in use and the availability of NAVTEX for the transmission of messages on behalf of SAR authorities in relation to SAR operations and incidents, including guidance on the appropriate type and content of these messages. 23. The Sub-Committee approved the draft terms of reference for the 16th meeting of the Joint IMO/ITU Experts Group on Maritime Radiocommunication Matters and agreed with the advice by the Group that five days were required for the meeting, which is programmed to be held 6 to 10 July 2020 at the IMO in London. The NCSR 7 also endorsed the re-establishment of the Correspondence Group on the Modernization of the GMDSS, under the coordination of United States, and approved its terms of reference. The contact details for the coordinator are: Mr. Robert L. Markle Markle Marine Safety Services 206 Johnston Farm Lane Woodstock, GA 30188 United States  Tel./Text: +1 703 283-2266 Email: [email protected] Agenda Item 12 - Response to matters related to the radiocommunication ITU-R study group and ITU World Radiocommunication Conference 24. Under the discussions covering the technical standardization for public mobile networks in the context of maritime safety, the Sub-Committee noted the discussions at IMO/ITU EG 15 on technical standardization for public mobile networks in the context of maritime safety and that the Experts Group, noting that IALA had already been approached by the 3rd Generation Partnership Project (3GPP), had invited IALA to keep IMO informed of future developments. In this context, the Sub-Committee noted also the information provided by IALA on considerations made by IALA with respect to developments within 3GPP that could support the maritime domain. 25. The Sub-Committee considered information provided by the Republic of Korea (NCSR 7/12/10), commenting on document NCSR 7/12, and proposing that IMO should monitor and investigate the use of public broadband communication and the standardization work of emerging maritime communication technologies related to maritime safety and should support standardization work to be harmonized with the GMDSS. IHO Secretariat comment: This has the potential to open up the provision of MSI via the mobile-phone network and download from websites. It would change the operational procedures of NAV and MET Area Coordinators and may open up the promulgation of MSI to commercial third parties with current authorities/organizations retaining responsibility for the original information/data. 26. After consideration, the Sub-Committee invited interested Member States and international organizations to submit relevant proposals to IMO/ITU EG 16 in order to start deliberations on this matter. Agenda Item 14 - Developments in GMDSS satellite services 27. The Sub-Committee considered information provided by China (NCSR 7/14) on BeiDou Message Service System (BDMSS), inviting the Sub-Committee to verify and evaluate the information on pre-assessment of BDMSS in relation to the criteria established by resolution A.1001(25) and to consider inviting IMSO to conduct the technical and operational assessment of BDMSS. 28. After consideration, the Sub-Committee, noting general support for the proposal by China, invited IMSO to conduct the technical and operational assessment of BDMSS and provide a technical and operational assessment report for consideration by the NCSR Sub- Committee. The IMSO advised that it was ready to undertake the technical and operational assessment of BDMSS; that a group of experts would be established for this purpose; and that interested parties willing to participate in this work should contact IMSO. IHO Secretariat comment: It is anticipated that WWNWS-SC and WWMIWS-C members will be invited to provide the technical and operational expertise for this assessment. 29. The Sub-Committee noted the information provided by IMSO (NCSR 7/INF.16) on the progress of the implementation of recognized maritime mobile satellite services by Iridium. IMSO advised that the Letter of Compliance, which marked the entry into force of Public Service Agreement (PSA) and the commencement of Iridium's financial obligations to IMSO in respect of the oversight of GMDSS, had been issued on 19 December 2019. Agenda Item 21 - Election of Chair and Vice-Chair for 2021 30. The Sub-Committee unanimously elected Mr Ringo Lakeman (Netherlands), as Chair, and Mr Nigel Clifford (New Zealand), as Vice-Chair, for 2021. Agenda Item 22 - Any other business 31. During the discussion on the review of IMO publications related to navigation, communication and search and rescue, general support was expressed for the aim of the proposal for the enhancement of IMO publications. However, some concerns were expressed regarding the establishment of editorial groups of experts to assist with the review and update of publications. The Sub-Committee, recognizing the importance of this matter, as well as the need for feedback from relevant experts before taking any final decisions. It was recognized by the IMO Secretariat that the WWNWS-SC is already undertaking this task with respect to MSI documents. 32. The Sub-Committee considered information provided by Canada (NCSR 7/22/2) seeking clarifications on the guidance for portrayal of Maritime safety information (MSI) set out in SN.1/Circ.243/Rev.2 on Guidelines for the presentation of navigation-related symbols, terms and abbreviations and, in particular, in connection with the development of product specifications for Navigational Warnings (contained in IHO S-124) for use in ECDIS using IHO's S-100 data modelling framework. 33. In view of relatively far future date when the new standards should be applied, the Sub- Committee noted that there should be no negative consequences in cancelling already- introduced MSI symbol. The Sub-Committee agreed that the best solution would be to cancel retrospectively the introduction of the MSI symbol which was introduced in SN.1/Circ.243/Rev.2 as from 14 June 2019, and developed a draft corrigendum as SN.1/Circ.243/Rev.2/Corr.1, as set out in annex 7. 34. During consideration, the Sub-Committee expressed the need for a better way of coordinating and managing the maintenance of navigation related symbols in the future. It would be important to facilitate the ability for users to contribute to the improvement of symbols, as envisaged in Human Centred Design, while providing the Organization with a way to maintain standardization, which is important to the user experience and as a result, safe navigation. IHO Secretariat comment: Noting these comments, the IHO, through NCWG and NIPWG, needs to be closely involved in this future work. The Chair of the S-124PT, who attended NCSR 7, will take this MSI portrayal work as part of the S-124 development. 35. Accordingly, the Sub-Committee invited Member States and international organizations to inform, as soon as possible, the relevant stakeholders of this correction, as appropriate, upon the approval of the corrigendum by the Committee, at its next at its next session in May 2020. 36. The Sub-Committee considered a proposal by the Republic of Korea (NCSR 7/22/3) on the development of guidelines for the use of Electronic nautical publications (ENPs) in order to unify the implementation of SOLAS regulation V/19.2.1.4. After consideration, the Sub- Committee invited interested Member States and international organizations to submit a proposal for a new output to the Committee, as appropriate. IHO Secretariat comment: This may have an impact on the work of NIPWG; consideration should be given for the submission of a comment paper to MSC 102, deadline 24 March 2020. 37. The Sub-Committee considered a report from IHO (NCSR 7/22/5) presenting a status of IHOʹs ECDIS-related standards and a roadmap of the introduction of the next generation of S-101 Electronic navigational charts (ENC); explaining the resulting implications for existing and new ECDIS installations; and proposing consideration of amendments to resolution MSC.232(82) on Revised Performance standards for Electronic chart display and information systems (ECDIS) to include references to S-100 and S-101, with regard to ECDIS equipment installed on or after 1 January 2024. 38. After consideration, the Sub-Committee: .1 acknowledged the ongoing effort of IHO to develop and test S-100 based data product specifications, as well as the proposed introduction of IHOʹs S-101 ENCs as a transfer standard for official charts in ECDIS; and .2 agreed that the amendments to resolution MSC.232(82) could be considered at a future session under the existing output on the Committee's post-biennial agenda on "Revision of ECDIS Guidance for good practice (MSC.1/Circ.1503/Rev.1)" and, in this respect, invited the Committee to expand this output to include consideration of amendments to resolution MSC.232(82). IHO Secretariat comment: It is requested that IHO Member States express their support for the Secretariat´s submission in Annex B at MSC 102 for its inclusion in the Work Programme of NCSR as an output of NCSR 8 and for it to be completed in one session rather than be tied to the completion of the revision of the MSC.1/Circ.1503, for which two sessions have been allocated. To this end Member States are encouraged to submit additional supporting comment papers to MSC 102 for which the deadline is 24 March 2020 and/or inform their respective IMO representatives to comment verbally in support once this item is introduced in plenary. 39. The Sub-Committee noted information provided by China (NCSR 7/INF.20) on future revision of ECDIS Guidance for good practice (MSC.1/Circ.1503/Rev.1) and inviting interested Member States and international organizations to participate in this work led by China. IHO Secretariat comment: This is related to China's submission MSC 99/12/10, which provided comments on implementation difficulties as to ECDIS software updates from the perspective of statutory surveys. It analysed the root cause and proposes three recommendations. IHO File No. S3/3075 Annex B to IHO CL 13/2020 E MARITIME SAFETY COMMITTEE MSC 102/21/x 102nd session ?? March 2020 Agenda item 21 Original: ENGLISH WORK PROGRAMME Comments on the proposal for revision of Revised Performance standards for Electronic chart display and information systems (ECDIS) (MSC.232(82)) contained in document MSC 102/16 Submitted by the International Hydrographic Organization (IHO) SUMMARY Executive summary: This document provides comments on document MSC 102/16, in particular the proposed revision of MSC.232(82) highlighted as proposed in IHO report on monitoring of ECDIS issues to NCSR 7 (NSCR 7/22/5). Strategic direction, if 6 applicable: Output: 164 Action to be taken: Paragraph 5 Related documents: MSC 102/16, NCSR 7/23, NCSR 7/22/5, MSC.232(82) 1. This document is submitted in accordance with paragraph 6.12.5 of the Guidelines on the organization and method of work of the Maritime Safety Committee and the Marine Environment Protection Committee and their subsidiary bodies (MSC-MEPC.1/Circ.4/Rev.4). This submission comments on document MSC 102/16 (Secretariat), specifically on the status of ECDIS-related standards and the roadmap for the introduction of the next generation of Electronic navigational charts (ENC) as highlighted in paragraph 3.4.3 and discussed in NCSR 7/23 paragraphs 22.10 and 22.11. 2. At NCSR 7, the IHO submitted document NCSR 7/22/5, which explained the implications for existing and new ECDIS installations resulting from the introduction of an additional format for official Electronic Navigational Charts (ENCs) titled S-101. The IHO proposed amendments to resolution MSC.232(82) on Revised Performance standards for Electronic chart display and information systems (ECDIS) to include references to the base line IHO publication S-100, and the specifications of the S-101 ENC format with regard to ECDIS equipment. 3. The IHO fully supports the inclusion of the revision of MSC.232(82) in the NCSR 8 agenda under the existing output “Revision of ECDIS Guidance for good practice (MSC.1/Circ.1503/Rev.1)”. 4. In preparation for NCSR 8 and to assist the revision process, the IHO intends to submit proposed amendments for both MSC.232(82) and MSC.1/Circ.1503/Rev.1 under the agenda item “Any Other Business – Report on monitoring ECDIS issues” to NCSR 8 for consideration by the Sub-Committee. The IHO believes that the revision to MSC.232(82) can be completed in one session. Action requested of the Committee 5. The Committee is invited to consider the above comments and take action as appropriate. *** Saatja: CL-LC <[email protected]> Saadetud: 12.03.2020 13:02 Adressaat: INFO <[email protected]> Teema: CL 13/2020 Manused: djhdihoikbnbkejm.png; CL13_2020_EN_v1.pdf Dear Hydrographer, Please find attached : - CL 13/2020: REPORT ON THE 7TH SESSION OF THE IMO SUB-COMMITTEE,ON NAVIGATION, COMMUNICATIONS AND SEARCH AND RESCUE (NCSR 7) Kind regards