164

Geo-Mar  Lett  (2017)  37:163-170

*£)  Springer

Fig.  1  Simulation  of  two
hypothetical  oil  releases  on  15th
March  2008  at  high  tide,  based  on
the  oil  drift  model  PADM  and
PELETS-2D.  Black  ship
symbols  indicate  locations  of
assumed  accidents,  dots  dispersed
oil,  filled  circles  undispersed  oil
on  surface,  light  blue  intertidal
areas  of  Wadden  Sea.  Particle
locations  calculated  with  PADM
and  PELETS-2D  are  colour
coded  in  red  and  blue
respectively.  Centres  of  gravity  of
simulated  particle  clouds  are
indicated  by  white  squares  for
PELETS  and  white  triangles  for
PADM.  Top  panel  Particle
locations  for  scenario  1  after  5
days,  four  bottom  panels  particle
locations  for  scenario  2  after  1  to
5  days

Scenario  1  after  5  days:

54°30'0"N
PADM  -  dispersed
O  PADM  -  undispersed
A  Center  of  gravity  PADM
PELETS  -  dispersed
O  PELETS  -  undispersed
□  Center  of  gravity  PELETS

Amrum«  ^
/  0
Scenario  1

-  54°0'0"N

7°0'0"E

7°30'0"E  8°0'0"E

8°30'0"E

S

1  day

2  days

J.

7=^

3  days

5  days

J.

low,  its  application  would  increase  the  dissolution  of  toxic
oil  components  in  the  sea.  Therefore,  the  application  of
dispersants  may  be  inappropriate  in  the  vicinity  of  sensitive ­
  habitats  if  concentrations  are  expected  to  stay  high
long  enough  for  toxic  effects.  Some  sub-lethal  effects

from  an  exposure  of  fish  to  dispersed  oil  were  observed
in  the  DISCOBIOL  research  program  (Le  Floch  et  al.
2014).  Toxic  effects  become  less  likely  when  dispersants
are  applied  in  deep  water  with  sufficiently  high  mixing
rates  (EMSA  2009;  Lee  et  al.  2011).