Anthropogenic halocarbons from ballast water treatment

Transcription

1 Shipping and the Environment - Gothenburg October 25 th, 2017 Anthropogenic halocarbons from ballast water treatment Josefine Maas 1, Susann Tegtmeier 1, Birgit Quack 1, Arne Biastoch 1 1 GEOMAR Helmholtz Centre for Ocean Research Kiel

2 Ballast Water Management Seebens et al.,

3 Ballast Water Management Industrial shipping as major vector for introduction of non-indigenous species Seebens et al.,

4 Ballast Water Management Industrial shipping as major vector for introduction of non-indigenous species IMO Ballast Water (BW) Management Convention (IMO, 2004) in force since Sep Seebens et al.,

5 Ballast Water Management Industrial shipping as major vector for introduction of non-indigenous species IMO Ballast Water (BW) Management Convention (IMO, 2004) in force since Sep Estimates of tons BW discharged annually Seebens et al.,

6 Halocarbons in Ballast Water Halocarbons are disinfection by-products (DBPs) in ballast water treatment systems (BWTS) (Werschkun et al., 2012) 3

7 Halocarbons in Ballast Water Halocarbons are disinfection by-products (DBPs) in ballast water treatment systems (BWTS) (Werschkun et al., 2012) DBPs: 3

8 Halocarbons in Ballast Water Halocarbons are disinfection by-products (DBPs) in ballast water treatment systems (BWTS) (Werschkun et al., 2012) DBPs: - Bromoform is main compound - High concentration in chemical BWTS (chlorination) - Found in all types of BWTS - Environmental impacts not sufficiently investigated 3

9 Halocarbons in Ballast Water Halocarbons are disinfection by-products (DBPs) in ballast water treatment systems (BWTS) (Werschkun et al., 2012) DBPs: - Bromoform is main compound - High concentration in chemical BWTS (chlorination) - Found in all types of BWTS - Environmental impacts not sufficiently investigated Impacts of Bromoform (CHBr 3 ): 3

10 Halocarbons in Ballast Water Halocarbons are disinfection by-products (DBPs) in ballast water treatment systems (BWTS) (Werschkun et al., 2012) DBPs: - Bromoform is main compound - High concentration in chemical BWTS (chlorination) - Found in all types of BWTS - Environmental impacts not sufficiently investigated Impacts of Bromoform (CHBr 3 ): - High ozone depletion potential - Change of radiative forcing - Decline of atmospheric oxidising capacity 3

11 Bromoform in BW 4

12 Bromoform in BW IMO SeaW 4 IMO BrackW

13 Bromoform in BW 4 Chl Chl IMO SeaW IMO BrackW

14 Bromoform in BW 4 Chl Chl UV IMO SeaW IMO BrackW

15 Bromoform in BW Chemical Treatment, e.g. Chlorination, Ozonation 4 Chl Chl UV IMO SeaW IMO BrackW

16 BW vs. Ocean Concentration Natural halocarbons Chemical BW treatment 5

17 BW vs. Ocean Concentration Natural halocarbons Chemical BW treatment Chlorination Ozonation DPBs ~900 nmol/l Bromoform BW concentration 5

18 BW vs. Ocean Concentration Natural halocarbons Chemical BW treatment Chlorination Ozonation after Ziska et al., 2013 ~40 pmol/l Bromoform Shelf water concentration DPBs ~900 nmol/l Bromoform BW concentration 5

19 BW vs. Ocean Concentration Natural halocarbons Chemical BW treatment Chlorination Ozonation after Ziska et al., 2013 ~40 pmol/l Bromoform Shelf water concentration DPBs How do DBPs spread in the surface ocean after BW discharge? ~900 nmol/l Bromoform BW concentration 5

20 Simulation of BW Spread with NEMO-ORCA12 6

21 Simulation of BW Spread with NEMO-ORCA12 NEMO-ORCA12 high-resolution (1/12 ) velocity field Continuous input of particles at each time step One harbour/region as release area -> Singapore 6

22 Simulation of BW Spread with NEMO-ORCA12 NEMO-ORCA12 high-resolution (1/12 ) velocity field Continuous input of particles at each time step One harbour/region as release area -> Singapore 6

23 Singapore BW Experiment Concentration 0.5yr Surface particle density -> Bromoform concentration [pmol/l] 7

24 Singapore BW Experiment Concentration 0.5yr Surface particle density -> Bromoform concentration [pmol/l] 7

25 Singapore BW Experiment Concentration 0.5yr Surface particle density -> Bromoform concentration [pmol/l] Oceanic and atmospheric sinks are taken into account 7

26 Singapore BW Experiment Concentration 0.5yr Surface particle density -> Bromoform concentration [pmol/l] Oceanic and atmospheric sinks are taken into account Surface concentrations from one harbour reach up to 30 pmol/l 7

27 Singapore BW Experiment Concentration 0.5yr Surface particle density -> Bromoform concentration [pmol/l] Oceanic and atmospheric sinks are taken into account Surface concentrations from one harbour reach up to 30 pmol/l ~40 pmol/l Bromoform Shelf water concentration ~30 pmol/l Bromoform Singapore BW concentration 7

28 Singapore BW experiment Concentration 1yr 8

29 Singapore BW Experiment Concentration 1yr Bromoform from BW concentrates in Strait of Malakka 8

30 Summary 9

31 Summary Bromoform concentration after chemical BW treatment is ~900 nmol/l 9

32 Summary Bromoform concentration after chemical BW treatment is ~900 nmol/l Singapore harbour only, causes up to 30 pmol/l bromoform at surface (same magnitude as natural) 9

33 Summary Bromoform concentration after chemical BW treatment is ~900 nmol/l Singapore harbour only, causes up to 30 pmol/l bromoform at surface (same magnitude as natural) DBP spread is dependent on regional and coastal processes 9

34 Summary Bromoform concentration after chemical BW treatment is ~900 nmol/l Singapore harbour only, causes up to 30 pmol/l bromoform at surface (same magnitude as natural) DBP spread is dependent on regional and coastal processes Significant contribution to global anthropogenic halocarbons expected 9

35 Thank you for your attention!

36 ORCA12: Depth Evolvement ORCA12: 78% 1/12 ~8km XX const. depth layers Global velocity fields 5 day output No tides

37 Harbours SE Asia

38 Singapore BW experiment Scenarios Sea-Air flux from mixed layer Const. flux rate Degradation Sea-air flux stronger than degradation Less flux in MLD than const. flux rate