At this point we would like to present a brief comparison of our results concerning constituent-specific light scattering coefficients with literature data available for different PI3K inhibitor review coastal sea waters. For their Baltic samples, Babin et al. (2003a) reported an average mass-specific

scattering coefficient bp* (555) of 0.49 m2 g−1 and its geometric standard deviation (applied as a factor) of 1.7, which gives a range of bp* (555) between 0.29 and 0.83 m2 g−1. Their average value is somewhat smaller than ours, but the range is not far from the one we found for southern Baltic samples: in fact, we obtained an average bp* (555) of 0.64 m2 g−1 and a range (± SD) from 0.34 to 0.94 m2 g−1. Also, in terms of the shape of the bp spectrum, Babin et al. (2003a) reported that average slopes were distinctly less steep than the λ−1 function (in our case, as we already mentioned, the average RAD001 manufacturer slope was about –0.4). For the tropical coastal waters off eastern Australia Oubelkheir et al. (2006) reported an average value of bp*(555) of 0.85 m2 g−1 (± 0.48 m2 g−1) for the majority of their bay water samples. They also mentioned a much

wider range of values from estuarine and offshore waters (from ca 0.5 m2 g−1 to as much as 2.3 m2 g−1). In another work, Stavn & Richter (2008) estimated mass-specific scattering coefficients at 555 nm for the organic fraction of their samples from the northern Gulf of Mexico to be in some cases as low as 0.32 and in others as high as 1.2 m2 g−1. All these examples show that the PRKACG variability in the mass-specific scattering coefficient bp* that we recorded in the southern Baltic does not seem to be unusual. From the work of McKee & Cunningham (2006) we can also cite values of chlorophyll-specific coefficients of scattering and backscattering. For Irish Sea waters they estimated values of

those coefficients for their set of organic-dominated samples. In fact they reported the average value of bp(Chl a) (555) to be 0.36 m2 mg−1 (±0.04 m2 mg−1), which is higher than the average we obtained for the southern Baltic (recall that we reported a value of 0.27 m2 mg−1 (SD = 0.21 m2 mg−1)); but when we consider ranges reported rather than average values alone they do not seem to be contradictory. In the case of the chlorophyll-specific backscattering coefficient McKee & Cunningham (2006) also reported an average value higher than that resulting from our database (their average of bbp*(Chl a)(470) was 0.005 m2 mg−1 (±0.0009 m2 mg−1), while for the closest available wavelength we reported bbp*(Chl a) (488) of 0.003 m2 mg−1 (±0.0025 m2 mg−1)), but again our ranges overlap most of their data, so they too are not exclusive. We would now like to make some final comments on the reported variability of different constituent-specific IOPs.