Climate Change and the European Water Dimension - Agri ...

VI.F.6. The potential influences of climate change on POPs
Figure VI.F.3. Conceptual diagram of input and loss mechanisms controlling
atmospheric concentrations of POPs (adapted from Sweetman and Jones, 2000).
PRIMARY
SOURCE
ADVECTION
WET / DRY
DEPOSITION
•OH •OH RADICAL
DEGRADATION
The direct effects of temperature
As noted in the previous section, temperature is an important driver to the global
cycling of POPs. Several important processes are temperature dependent, notably:
1. Emissions from some primary sources:
PCBs and PBDEs have been widely used in urban areas in many industrialised
countries, and may be subject to diffusive emissions from their primary sources –
PCBs from sealants, transformers, electronic equipment etc; PBDEs from fireretarded
fabrics and treated polyurethane foam, for example (Breivik et al., 2002a;
2002b; Prevedouros et al., 2004).
2. Emissions from secondary sources:
Emissions from the key environmental ‘repositories’ of soils, sediments, vegetation,
water (inland and marine) are obviously influenced by temperature. Volatilisation
rates of pesticides from soils are temperature dependent, although other factors also
exert a strong influence, notably soil moisture status, organic matter content, depth of
compound incorporation, and wind field and intensity.
3. Gas: particle partitioning and subsequent impacts on deposition processes:
210
AIR
SOIL OR WATER BODY
(secondary source)
BIODEGRADATION
PHYSICAL REMOVAL
(e.g. BURIAL)
VOLATILISATION /
GASEOUS DEPOSITION
BOUND RESIDUE FORMATION