The metric of the parameter ?Duration (quarter 1)? is a number of days of impulsive emissions recorded for the quarter 1 of the year 2016. The impulsive emissions selected for this evaluation, as well as their noise levels, follow the enumeration of data recommended by TG Noise (Dekeling, R.P.A., Tasks, M.L., Van der Graaf, A.J., Ainhouse, M.A, Andersson, M.H., André, M., Borsani, J.F., Brensing, K., Castellote, M., Cronin, D., Dalen, J., Folegot, T., Robinson, S.P., Sigala, P., Sutton, G., Thomsen, F., Werner, S., Wittekind, D., Young, J.V. 2014. Monitoring for Underwater Noise in European Seas, Part II: Monitoring Guidance Specifications, JRC Scientific and Policy Report EUR 26555 EN, Publications Office of the European Union, Luxembourg, p. 49.). For the risk of disturbance, all impulsive emissions shall be taken into account, regardless of their noise level. The emission days identified in the northern part of the SRM GdG come exclusively from explosions during counter-mining operations. The cumulative number of impulsive emission days (all noise levels combined) in the northern part of the SRM GdG is 0 days for the quarter 1 of 2016. At present, however, no time threshold is defined, which makes it impossible to assess whether or not the parameter has been reached.

The metric of the parameter ?Duration (quarter 2)? is a number of days of impulsive emissions recorded for the quarter 2 of the year 2016. The impulsive emissions selected for this evaluation, as well as their noise levels, follow the enumeration of data recommended by TG Noise (Dekeling, R.P.A., Tasks, M.L., Van der Graaf, A.J., Ainhouse, M.A, Andersson, M.H., André, M., Borsani, J.F., Brensing, K., Castellote, M., Cronin, D., Dalen, J., Folegot, T., Robinson, S.P., Sigala, P., Sutton, G., Thomsen, F., Werner, S., Wittekind, D., Young, J.V. 2014. Monitoring for Underwater Noise in European Seas, Part II: Monitoring Guidance Specifications, JRC Scientific and Policy Report EUR 26555 EN, Publications Office of the European Union, Luxembourg, p. 49.). For the risk of disturbance, all impulsive emissions shall be taken into account, regardless of their noise level. The emission days identified in the northern part of the SRM GdG come exclusively from explosions during counter-mining operations. The cumulative number of impulsive emission days (all noise levels combined) in the northern part of the SRM GdG is 8 days for the quarter 2 of 2016. At present, however, no time threshold is defined, which makes it impossible to assess whether or not the parameter has been reached.

The metric of the parameter ?Duration (quarter 3)? is a number of days of impulsive emissions recorded for the quarter 3 of the year 2016. The impulsive emissions selected for this evaluation, as well as their noise levels, follow the enumeration of data recommended by TG Noise (Dekeling, R.P.A., Tasks, M.L., Van der Graaf, A.J., Ainhouse, M.A, Andersson, M.H., André, M., Borsani, J.F., Brensing, K., Castellote, M., Cronin, D., Dalen, J., Folegot, T., Robinson, S.P., Sigala, P., Sutton, G., Thomsen, F., Werner, S., Wittekind, D., Young, J.V. 2014. Monitoring for Underwater Noise in European Seas, Part II: Monitoring Guidance Specifications, JRC Scientific and Policy Report EUR 26555 EN, Publications Office of the European Union, Luxembourg, p. 49.). For the risk of disturbance, all impulsive emissions shall be taken into account, regardless of their noise level. The emission days identified in the northern part of the SRM GdG come exclusively from explosions during counter-mining operations. The cumulative number of impulsive emission days (all noise levels combined) in the northern part of the SRM GdG is 7 days for the quarter 3 of 2016. At present, however, no time threshold is defined, which makes it impossible to assess whether or not the parameter has been reached.

The metric of the parameter ?Duration (quarter 4)? is a number of days of impulsive emissions recorded for the quarter 4 of the year 2016. The impulsive emissions selected for this evaluation, as well as their noise levels, follow the enumeration of data recommended by TG Noise (Dekeling, R.P.A., Tasks, M.L., Van der Graaf, A.J., Ainhouse, M.A, Andersson, M.H., André, M., Borsani, J.F., Brensing, K., Castellote, M., Cronin, D., Dalen, J., Folegot, T., Robinson, S.P., Sigala, P., Sutton, G., Thomsen, F., Werner, S., Wittekind, D., Young, J.V. 2014. Monitoring for Underwater Noise in European Seas, Part II: Monitoring Guidance Specifications, JRC Scientific and Policy Report EUR 26555 EN, Publications Office of the European Union, Luxembourg, p. 49.). For the risk of disturbance, all impulsive emissions shall be taken into account, regardless of their noise level. The emission days identified in the northern part of the SRM GdG come exclusively from explosions during counter-mining operations. The cumulative number of impulsive emission days (all noise levels combined) in the northern part of the SRM GdG is 5 days for the quarter 4 of 2016. At present, however, no time threshold is defined, which makes it impossible to assess whether or not the parameter has been reached.

The metric of the ?Duration per year? parameter shall be a number of days of impulsive emissions recorded for the year 2016 and the spatial distribution of those emission days in the UMR, i.e. a percentage of meshes in the UMR for which at least one impulsive emission has been identified. The impulsive emissions selected for this evaluation, as well as their noise levels, follow the enumeration of data recommended by TG Noise (Dekeling, R.P.A., Tasks, M.L., Van der Graaf, A.J., Ainhouse, M.A, Andersson, M.H., André, M., Borsani, J.F., Brensing, K., Castellote, M., Cronin, D., Dalen, J., Folegot, T., Robinson, S.P., Sigala, P., Sutton, G., Thomsen, F., Werner, S., Wittekind, D., Young, J.V. 2014. Monitoring for Underwater Noise in European Seas, Part II: Monitoring Guidance Specifications, JRC Scientific and Policy Report EUR 26555 EN, Publications Office of the European Union, Luxembourg, p. 49.). For the risk of disturbance, all impulsive emissions shall be taken into account, regardless of their noise level. The emission days identified in the northern part of the SRM GdG come exclusively from explosions during counter-mining operations. The cumulative number of impulsive emissions (all noise levels combined) in the northern part of the SRM GdG is 20 days for the whole of 2016. The aggregate number of meshes for which at least one emission has been recorded for the year 2016 shall be 15, representing a spatial hold of 6.41 % of the total area of the northern part of the SRM GtG. At present, there has been no consensus on the values of time and space thresholds at both national and European level, which makes it impossible to assess whether or not this parameter has been reached.

The metric of the parameter ?Duration (quarter 1)? is a number of impulsive (strong) emission days identified for the quarter 1 of 2016. The impulsive emissions selected for this evaluation, as well as their noise levels, follow the enumeration of data recommended by TG Noise (Dekeling, R.P.A., Tasks, M.L., Van der Graaf, A.J., Ainhouse, M.A, Andersson, M.H., André, M., Borsani, J.F., Brensing, K., Castellote, M., Cronin, D., Dalen, J., Folegot, T., Robinson, S.P., Sigala, P., Sutton, G., Thomsen, F., Werner, S., Wittekind, D., Young, J.V. 2014. Monitoring for Underwater Noise in European Seas, Part II: Monitoring Guidance Specifications, JRC Scientific and Policy Report EUR 26555 EN, Publications Office of the European Union, Luxembourg, p. 49.). For the risk of excess mortality, only the impulsive and high acoustic levels of noise emissions shall be taken into account. The emission days identified in the northern part of the SRM GdG come exclusively from explosions during counter-mining operations. The cumulative number of days of strong and very strong levels of emissions in the northern part of the SRM GdG is 0 days for the quarter 1 of 2016. At present, however, no time threshold is defined, which makes it impossible to assess whether or not the parameter has been reached.

The metric of the parameter ?Duration (quarter 2)? is a number of impulsive (strong) emission days identified for the quarter 2 of 2016. The impulsive emissions selected for this evaluation, as well as their noise levels, follow the enumeration of data recommended by TG Noise (Dekeling, R.P.A., Tasks, M.L., Van der Graaf, A.J., Ainhouse, M.A, Andersson, M.H., André, M., Borsani, J.F., Brensing, K., Castellote, M., Cronin, D., Dalen, J., Folegot, T., Robinson, S.P., Sigala, P., Sutton, G., Thomsen, F., Werner, S., Wittekind, D., Young, J.V. 2014. Monitoring for Underwater Noise in European Seas, Part II: Monitoring Guidance Specifications, JRC Scientific and Policy Report EUR 26555 EN, Publications Office of the European Union, Luxembourg, p. 49.). For the risk of excess mortality, only the impulsive and high acoustic levels of noise emissions shall be taken into account. The emission days identified in the northern part of the SRM GdG come exclusively from explosions during counter-mining operations. The cumulative number of days of strong and very strong levels of emissions in the northern part of the SRM GdG is 1 days for the quarter 2 of 2016. At present, however, no time threshold is defined, which makes it impossible to assess whether or not the parameter has been reached.

The metric of the parameter ?Duration (quarter 3)? is a number of impulsive (strong) emission days identified for the quarter 3 of 2016. The impulsive emissions selected for this evaluation, as well as their noise levels, follow the enumeration of data recommended by TG Noise (Dekeling, R.P.A., Tasks, M.L., Van der Graaf, A.J., Ainhouse, M.A, Andersson, M.H., André, M., Borsani, J.F., Brensing, K., Castellote, M., Cronin, D., Dalen, J., Folegot, T., Robinson, S.P., Sigala, P., Sutton, G., Thomsen, F., Werner, S., Wittekind, D., Young, J.V. 2014. Monitoring for Underwater Noise in European Seas, Part II: Monitoring Guidance Specifications, JRC Scientific and Policy Report EUR 26555 EN, Publications Office of the European Union, Luxembourg, p. 49.). For the risk of excess mortality, only the impulsive and high acoustic levels of noise emissions shall be taken into account. The emission days identified in the northern part of the SRM GdG come exclusively from explosions during counter-mining operations. The cumulative number of days of strong and very strong levels of emissions in the northern part of the SRM GdG is 1 days for the quarter 3 of 2016. At present, however, no time threshold is defined, which makes it impossible to assess whether or not the parameter has been reached.

The metric of the parameter ?Duration (quarter 4)? is a number of impulsive (strong) emission days identified for the quarter 4 of 2016. The impulsive emissions selected for this evaluation, as well as their noise levels, follow the enumeration of data recommended by TG Noise (Dekeling, R.P.A., Tasks, M.L., Van der Graaf, A.J., Ainhouse, M.A, Andersson, M.H., André, M., Borsani, J.F., Brensing, K., Castellote, M., Cronin, D., Dalen, J., Folegot, T., Robinson, S.P., Sigala, P., Sutton, G., Thomsen, F., Werner, S., Wittekind, D., Young, J.V. 2014. Monitoring for Underwater Noise in European Seas, Part II: Monitoring Guidance Specifications, JRC Scientific and Policy Report EUR 26555 EN, Publications Office of the European Union, Luxembourg, p. 49.). For the risk of excess mortality, only the impulsive and high acoustic levels of noise emissions shall be taken into account. The emission days identified in the northern part of the SRM GdG come exclusively from explosions during counter-mining operations. The cumulative number of days of strong and very strong levels of emissions in the northern part of the SRM GdG is 5 days for the quarter 4 of 2016. At present, however, a time threshold is not defined, which makes it impossible to assess whether or not the parameter has been reached.

The metric of the ?Duration per year? parameter shall be a number of days of impulsive emissions (strong and very high levels) identified for the year 2016 and the spatial distribution of those emission days in the UMR, i.e. a percentage of the UMR in which at least one impulsive emission has been identified. The impulsive emissions selected for this evaluation, as well as their noise levels, follow the enumeration of data recommended by TG Noise (Dekeling, R.P.A., Tasks, M.L., Van der Graaf, A.J., Ainhouse, M.A, Andersson, M.H., André, M., Borsani, J.F., Brensing, K., Castellote, M., Cronin, D., Dalen, J., Folegot, T., Robinson, S.P., Sigala, P., Sutton, G., Thomsen, F., Werner, S., Wittekind, D., Young, J.V. 2014. Monitoring for Underwater Noise in European Seas, Part II: Monitoring Guidance Specifications, JRC Scientific and Policy Report EUR 26555 EN, Publications Office of the European Union, Luxembourg, p. 49.). For the risk of excess mortality, only the impulsive and high acoustic levels of noise emissions shall be taken into account. The emission days identified in the northern part of the SRM GdG come exclusively from explosions during counter-mining operations. The cumulative number of impulsive and strong noise emission days in the northern part of the SRM GdG is 7 days for the whole of 2016. The aggregate number of meshes for which at least one emission has been recorded for the year 2016 shall be 2, representing a spatial hold of 0.85 % of the total area of the northern part of the SRM GtG. At present, there has been no consensus on the values of time and space thresholds at both national and European level, which makes it impossible to assess whether or not this parameter has been reached.

The parameter of the parameter ?Development of the underwater sound level (125 Hz)? is the difference between the maximum annual ambient noise levels between the reference year and the most recent year by a mesh band for the 125 Hz frequency band. The spatial distribution of the differences in maximum noise levels between the two years 2016 and 2012 (reference year for this assessment) shows an increase of 75 % of the meshes for the frequency band centred on 125 Hz. Proportion (%) of meshes in the northern part of SRM GtG showing an increase or decrease in maximum sound levels: 25 % increase ? 1 dB re 1 µPa2: 25 % increase ? 1 dB re 1 µPa2: 50 % Having regard to the lack of knowledge, high uncertainties and limited available in-situ data, no threshold for an increase in the maximum sound level per grid could be established. The infringement of the parameter is therefore considered to be ?unknown?.

The parameter of the parameter ?underwater noise (125 Hz)? is the annual median continuous noise at low frequency (125 Hz). For the year 2016, the median value of the maximum noise levels is 105 dB re 1 µPa2 for the one-third octave band centred at 125 Hz. Given the lack of knowledge, high uncertainties and limited available in-situ data, no threshold has been defined, which does not allow a conclusion on whether or not the parameter has been reached.

The parameter of the parameter ?Development of the underwater sound level (63 Hz)? is the difference between the maximum annual ambient noise levels between the reference year and the most recent year by a mesh band for the 63 Hz frequency band. The spatial distribution of the differences in maximum noise levels between the two years 2016 and 2012 (reference year for this assessment) shows an increase of 75 % of the meshes for the frequency band centred on 63 Hz. Proportion (%) of meshes in the northern part of SRM GtG showing an increase or decrease in maximum sound levels: 25 %.Increase ? 1 dB re 1 µPa2: 25 % increase ? 1 dB re 1 µPa2: 50 %.As regards the lack of knowledge, the high uncertainties and the limited in-situ data available, no threshold for an increase in the maximum sound level per grid could be established. The infringement of the parameter is therefore considered to be ?unknown?.

The parameter of the parameter ?underwater noise (63 Hz)? is the annual median continuous noise at low frequency (63 Hz). For the year 2016, the median value of the maximum noise levels is 108 dB re 1 µPa2 for the one-third octave band centred at 63 Hz. Given the lack of knowledge, high uncertainties and limited available in-situ data, no threshold has been defined, which does not allow a conclusion on whether or not the parameter has been reached.

The metric of the parameter ?Duration (quarter 1)? is a number of days of impulsive emissions recorded for the quarter 1 of the year 2016. The impulsive emissions selected for this evaluation, as well as their noise levels, follow the enumeration of data recommended by TG Noise (Dekeling, R.P.A., Tasks, M.L., Van der Graaf, A.J., Ainhouse, M.A, Andersson, M.H., André, M., Borsani, J.F., Brensing, K., Castellote, M., Cronin, D., Dalen, J., Folegot, T., Robinson, S.P., Sigala, P., Sutton, G., Thomsen, F., Werner, S., Wittekind, D., Young, J.V. 2014. Monitoring for Underwater Noise in European Seas, Part II: Monitoring Guidance Specifications, JRC Scientific and Policy Report EUR 26555 EN, Publications Office of the European Union, Luxembourg, p. 49.). For the risk of disturbance, all impulsive emissions shall be taken into account, regardless of their noise level. The emission days identified in the southern part of the SRM GdG come exclusively from explosions during counter-mining operations. The cumulative number of impulsive emission days (all noise levels combined) in the southern part of the SRM GdG is 0 days for the quarter 1 of 2016. At present, however, no time threshold is defined, which makes it impossible to assess whether or not the parameter has been reached.

The metric of the parameter ?Duration (quarter 2)? is a number of days of impulsive emissions recorded for the quarter 2 of the year 2016. The impulsive emissions selected for this evaluation, as well as their noise levels, follow the enumeration of data recommended by TG Noise (Dekeling, R.P.A., Tasks, M.L., Van der Graaf, A.J., Ainhouse, M.A, Andersson, M.H., André, M., Borsani, J.F., Brensing, K., Castellote, M., Cronin, D., Dalen, J., Folegot, T., Robinson, S.P., Sigala, P., Sutton, G., Thomsen, F., Werner, S., Wittekind, D., Young, J.V. 2014. Monitoring for Underwater Noise in European Seas, Part II: Monitoring Guidance Specifications, JRC Scientific and Policy Report EUR 26555 EN, Publications Office of the European Union, Luxembourg, p. 49.). For the risk of disturbance, all impulsive emissions shall be taken into account, regardless of their noise level. The emission days identified in the southern part of the SRM GdG come exclusively from explosions during counter-mining operations. The cumulative number of impulsive emission days (all noise levels combined) in the south of the SRM GdG is 1 days for the quarter 2 of 2016. At present, however, no time threshold is defined, which makes it impossible to assess whether or not the parameter has been reached.

The metric of the parameter ?Duration (quarter 3)? is a number of days of impulsive emissions recorded for the quarter 3 of the year 2016. The impulsive emissions selected for this evaluation, as well as their noise levels, follow the enumeration of data recommended by TG Noise (Dekeling, R.P.A., Tasks, M.L., Van der Graaf, A.J., Ainhouse, M.A, Andersson, M.H., André, M., Borsani, J.F., Brensing, K., Castellote, M., Cronin, D., Dalen, J., Folegot, T., Robinson, S.P., Sigala, P., Sutton, G., Thomsen, F., Werner, S., Wittekind, D., Young, J.V. 2014. Monitoring for Underwater Noise in European Seas, Part II: Monitoring Guidance Specifications, JRC Scientific and Policy Report EUR 26555 EN, Publications Office of the European Union, Luxembourg, p. 49.). For the risk of disturbance, all impulsive emissions shall be taken into account, regardless of their noise level. The emission days identified in the southern part of the SRM GdG come exclusively from explosions during counter-mining operations. The cumulative number of impulsive emission days (all noise levels combined) in the southern part of the SRM GdG is 0 days for the quarter 3 of 2016. At present, however, no time threshold is defined, which makes it impossible to assess whether or not the parameter has been reached.

The metric of the parameter ?Duration (quarter 4)? is a number of days of impulsive emissions recorded for the quarter 4 of the year 2016. The impulsive emissions selected for this evaluation, as well as their noise levels, follow the enumeration of data recommended by TG Noise (Dekeling, R.P.A., Tasks, M.L., Van der Graaf, A.J., Ainhouse, M.A, Andersson, M.H., André, M., Borsani, J.F., Brensing, K., Castellote, M., Cronin, D., Dalen, J., Folegot, T., Robinson, S.P., Sigala, P., Sutton, G., Thomsen, F., Werner, S., Wittekind, D., Young, J.V. 2014. Monitoring for Underwater Noise in European Seas, Part II: Monitoring Guidance Specifications, JRC Scientific and Policy Report EUR 26555 EN, Publications Office of the European Union, Luxembourg, p. 49.). For the risk of disturbance, all impulsive emissions shall be taken into account, regardless of their noise level. The emission days identified in the southern part of the SRM GdG come exclusively from explosions during counter-mining operations. The cumulative number of impulsive emission days (all noise levels combined) in the south of the SRM GdG is 1 days for the quarter 4 of 2016. At present, however, no time threshold is defined, which makes it impossible to assess whether or not the parameter has been reached.

The metric of the ?Duration per year? parameter shall be a number of days of impulsive emissions recorded for the year 2016 and the spatial distribution of those emission days in the UMR, i.e. a percentage of meshes in the UMR for which at least one impulsive emission has been identified. The impulsive emissions selected for this evaluation, as well as their noise levels, follow the enumeration of data recommended by TG Noise (Dekeling, R.P.A., Tasks, M.L., Van der Graaf, A.J., Ainhouse, M.A, Andersson, M.H., André, M., Borsani, J.F., Brensing, K., Castellote, M., Cronin, D., Dalen, J., Folegot, T., Robinson, S.P., Sigala, P., Sutton, G., Thomsen, F., Werner, S., Wittekind, D., Young, J.V. 2014. Monitoring for Underwater Noise in European Seas, Part II: Monitoring Guidance Specifications, JRC Scientific and Policy Report EUR 26555 EN, Publications Office of the European Union, Luxembourg, p. 49.). For the risk of disturbance, all impulsive emissions shall be taken into account, regardless of their noise level. The emission days identified in the southern part of the SRM GdG come exclusively from explosions during counter-mining operations. The cumulative number of impulsive emissions (all noise levels combined) in the southern part of the SRM GdG is 2 days for the whole of 2016. The aggregate number of meshes for which at least one emission has been recorded for the year 2016 shall be 2, representing a spatial hold of 0.9 % of the total surface area of the southern part of the SRM GdG. At present, there has been no consensus on the values of time and space thresholds at both national and European level, which makes it impossible to assess whether or not this parameter has been reached.

The metric of the parameter ?Duration (quarter 1)? is a number of impulsive (strong) emission days identified for the quarter 1 of 2016. The impulsive emissions selected for this evaluation, as well as their noise levels, follow the enumeration of data recommended by TG Noise (Dekeling, R.P.A., Tasks, M.L., Van der Graaf, A.J., Ainhouse, M.A, Andersson, M.H., André, M., Borsani, J.F., Brensing, K., Castellote, M., Cronin, D., Dalen, J., Folegot, T., Robinson, S.P., Sigala, P., Sutton, G., Thomsen, F., Werner, S., Wittekind, D., Young, J.V. 2014. Monitoring for Underwater Noise in European Seas, Part II: Monitoring Guidance Specifications, JRC Scientific and Policy Report EUR 26555 EN, Publications Office of the European Union, Luxembourg, p. 49.). For the risk of excess mortality, only the impulsive and high acoustic levels of noise emissions shall be taken into account. The emission days identified in the southern part of the SRM GdG come exclusively from explosions during counter-mining operations. The cumulative number of days of strong and very strong levels of emissions in the southern part of the SRM GdG is 0 days for the quarter 1 of 2016. At present, however, no time threshold is defined, which makes it impossible to assess whether or not the parameter has been reached.

The metric of the parameter ?Duration (quarter 2)? is a number of impulsive (strong) emission days identified for the quarter 2 of 2016. The impulsive emissions selected for this evaluation, as well as their noise levels, follow the enumeration of data recommended by TG Noise (Dekeling, R.P.A., Tasks, M.L., Van der Graaf, A.J., Ainhouse, M.A, Andersson, M.H., André, M., Borsani, J.F., Brensing, K., Castellote, M., Cronin, D., Dalen, J., Folegot, T., Robinson, S.P., Sigala, P., Sutton, G., Thomsen, F., Werner, S., Wittekind, D., Young, J.V. 2014. Monitoring for Underwater Noise in European Seas, Part II: Monitoring Guidance Specifications, JRC Scientific and Policy Report EUR 26555 EN, Publications Office of the European Union, Luxembourg, p. 49.). For the risk of excess mortality, only the impulsive and high acoustic levels of noise emissions shall be taken into account. The emission days identified in the southern part of the SRM GdG come exclusively from explosions during counter-mining operations. The cumulative number of days of strong and very strong levels of emissions in the south of the SRM GdG is 1 days for the quarter 2 of 2016. At present, however, no time threshold is defined, which makes it impossible to assess whether or not the parameter has been reached.

The metric of the parameter ?Duration (quarter 3)? is a number of impulsive (strong) emission days identified for the quarter 3 of 2016. The impulsive emissions selected for this evaluation, as well as their noise levels, follow the enumeration of data recommended by TG Noise (Dekeling, R.P.A., Tasks, M.L., Van der Graaf, A.J., Ainhouse, M.A, Andersson, M.H., André, M., Borsani, J.F., Brensing, K., Castellote, M., Cronin, D., Dalen, J., Folegot, T., Robinson, S.P., Sigala, P., Sutton, G., Thomsen, F., Werner, S., Wittekind, D., Young, J.V. 2014. Monitoring for Underwater Noise in European Seas, Part II: Monitoring Guidance Specifications, JRC Scientific and Policy Report EUR 26555 EN, Publications Office of the European Union, Luxembourg, p. 49.). For the risk of excess mortality, only the impulsive and high acoustic levels of noise emissions shall be taken into account. The emission days identified in the southern part of the SRM GdG come exclusively from explosions during counter-mining operations. The cumulative number of days of strong and very strong levels of emissions in the southern part of the SRM GdG is 0 days for the quarter 3 of 2016. At present, however, no time threshold is defined, which makes it impossible to assess whether or not the parameter has been reached.

The metric of the parameter ?Duration (quarter 4)? is a number of impulsive (strong) emission days identified for the quarter 4 of 2016. The impulsive emissions selected for this evaluation, as well as their noise levels, follow the enumeration of data recommended by TG Noise (Dekeling, R.P.A., Tasks, M.L., Van der Graaf, A.J., Ainhouse, M.A, Andersson, M.H., André, M., Borsani, J.F., Brensing, K., Castellote, M., Cronin, D., Dalen, J., Folegot, T., Robinson, S.P., Sigala, P., Sutton, G., Thomsen, F., Werner, S., Wittekind, D., Young, J.V. 2014. Monitoring for Underwater Noise in European Seas, Part II: Monitoring Guidance Specifications, JRC Scientific and Policy Report EUR 26555 EN, Publications Office of the European Union, Luxembourg, p. 49.). For the risk of excess mortality, only the impulsive and high acoustic levels of noise emissions shall be taken into account. The emission days identified in the southern part of the SRM GdG come exclusively from explosions during counter-mining operations. The cumulative number of days of strong and very strong levels of emissions in the south of the SRM GdG is 1 days for the quarter 4 of 2016. At present, however, a time threshold is not defined, which makes it impossible to assess whether or not the parameter has been reached.

The metric of the ?Duration per year? parameter shall be a number of days of impulsive emissions (strong and very high levels) identified for the year 2016 and the spatial distribution of those emission days in the UMR, i.e. a percentage of the UMR in which at least one impulsive emission has been identified. The impulsive emissions selected for this evaluation, as well as their noise levels, follow the enumeration of data recommended by TG Noise (Dekeling, R.P.A., Tasks, M.L., Van der Graaf, A.J., Ainhouse, M.A, Andersson, M.H., André, M., Borsani, J.F., Brensing, K., Castellote, M., Cronin, D., Dalen, J., Folegot, T., Robinson, S.P., Sigala, P., Sutton, G., Thomsen, F., Werner, S., Wittekind, D., Young, J.V. 2014. Monitoring for Underwater Noise in European Seas, Part II: Monitoring Guidance Specifications, JRC Scientific and Policy Report EUR 26555 EN, Publications Office of the European Union, Luxembourg, p. 49.). For the risk of excess mortality, only the impulsive and high acoustic levels of noise emissions shall be taken into account. The emission days identified in the southern part of the SRM GdG come exclusively from explosions during counter-mining operations. The cumulated number of impulsive and strong noise emission days in the southern part of the SRM GdG is 2 days for the whole of 2016. The aggregate number of meshes for which at least one emission has been recorded for the year 2016 shall be 2, representing a spatial hold of 0.9 % of the total area of the northern part of the SRM GtG. At present, there has been no consensus on the values of time and space thresholds at both national and European level, which makes it impossible to assess whether or not this parameter has been reached.

The parameter of the parameter ?Development of the underwater sound level (125 Hz)? is the difference between the maximum annual ambient noise levels between the reference year and the most recent year by a mesh band for the 125 Hz frequency band. The spatial distribution of the differences in maximum noise levels between the two years 2016 and 2012 (reference year for this assessment) shows an increase of 75 % of the meshes for the frequency band centred on 125 Hz. Proportion (%) of the meshes of the south of the SRM GdG showing an increase or decrease of the maximum sound levels: 25 % increase ? 1 dB re 1 µPa2: 25 % increase between 1-2 dB re 1 µPa²: 28 %. increase between 2-3 dB re 1 µPa2: 20 %. increase ? 3 dB re 1 µPa2: 2 %.As regards the lack of knowledge, the high uncertainties and the limited in-situ data available, no threshold for an increase in the maximum sound level per grid could be established. The infringement of the parameter is therefore considered to be ?unknown?.

The parameter of the parameter ?underwater noise (125 Hz)? is the annual median continuous noise at low frequency (125 Hz). For the year 2016, the median value of the maximum noise levels is 102 dB re 1 µPa2 for the one-third octave band centred at 125 Hz. Given the lack of knowledge, high uncertainties and limited available in-situ data, no threshold has been defined, which does not allow a conclusion on whether or not the parameter has been reached.

The parameter of the parameter ?Development of the underwater sound level (63 Hz)? is the difference between the maximum annual ambient noise levels between the reference year and the most recent year by a mesh band for the 63 Hz frequency band. The spatial distribution of the differences in maximum noise levels between the two years 2016 and 2012 (reference year for this assessment) shows an increase of 75 % of the meshes for the frequency band centred on 63 Hz. Proportion (%) of the meshes of the south of the SRM GdG showing an increase or decrease of the maximum sound levels: 25 %.Increase ? 1 dB re 1 µPa2: 25 % increase between 1-2 dB re 1 µPa²: 38 %. increase between 2-3 dB re 1 µPa2: 10 %. increase ? 3 dB re 1 µPa2: 2 %.As regards the lack of knowledge, the high uncertainties and the limited in-situ data available, no threshold for an increase in the maximum sound level per grid could be established. The infringement of the parameter is therefore considered to be ?unknown?.

The parameter of the parameter ?underwater noise (63 Hz)? is the annual median continuous noise at low frequency (63 Hz). For the year 2016, the median value of the maximum noise levels is 104 dB re 1 µPa2 for the one-third octave band centred at 63 Hz. Given the lack of knowledge, high uncertainties and limited available in-situ data, no threshold has been defined, which does not allow a conclusion on whether or not the parameter has been reached.