Regional Report on Sea-based Marine Litter in the ... - nowpap dinrac

<strong>Regional</strong> <strong>Report</strong> on Sea-based Marine Litter in the NOWPAP Region4.2. Floating litter monitoringSea-based marine litter can also betransported by winds and currents in theNOWPAP region. The JapanMeteorological Agency (JMA) has beenmonitoring floating plastics as one of themarine pollution observations including oilpollution and heavy metals in the seasadjacent to Japan and Northwest Pacificregion.JMA has been monitoring floating plasticsalong several observational lines (Figure 5)including 137° E line, which wasestablished in 1977. Floating pollutants arecounted by continuous observation fromthe bridges of research vessels during thedaytime. When observers find a floatingpollutant, they record its location and type.Figure 5. Observation lines of JMAresearch vessels (2007)Figure 6 shows the number of floatingplastics found annually every 5°longitude and latitude in the areasfrom 1981 to 2000. In general, thenumber of floating plastics becomessmaller with the distance from thecontinent. Also, the number of floatingplastics found in the sea adjacent toJapan is larger than those in the areasaround 20° N and in the sub-arcticregion. Relatively many floatingplastics were found between 30-35° N,south of the Kuroshio and theKuroshio Extension.Figure 6. Average distribution of floatingplastics between 1981 and 200010