[1] Analysis of satellite ocean color and wind speed data within the seasonal ice zone (SIZ) of the Southern Ocean sheds light on the physical processes that influence phytoplankton biomass distributions. A compilation of monthly averaged chlorophyll and percent sea ice cover data within the SIZ from 1997 to 2005 has been compared with monthly average wind speed data from 1999 to 2005. The size of the marginal ice zone (MIZ, areas of recent ice retreat) was fairly consistent from year to year, always peaking in December, with a mean area of 6.0 million km 2 . The mean area within the MIZ with phytoplankton blooms (chlorophyll exceeding 0.8 mg/m 3 ) was 0.36 million km 2 . While the bloom areal extent seems small compared to the MIZ, in reality, because of gaps in the chlorophyll data, blooming regions comprise a much larger fraction of the MIZ. Considering only areas with valid chlorophyll data, the percentage of the MIZ with blooms was 17%, 21%, and 24% for the months of December, January, and February, respectively. December always has the largest MIZ area, but MIZ mean chlorophyll concentrations sometimes do not peak until February. Wind speed strongly impacts phytoplankton bloom dynamics within the MIZ. There is an inverse relation between wind speed and bloom occurrence, with blooms largely suppressed at high wind speeds. At low wind speeds ($5 m/s), blooms are observed over about one third of the MIZ. Blooms are also much more frequent near the continent than in offshore waters, likely due to increased iron availability. Open ocean phytoplankton blooms in the Southern Ocean are likely to become iron-light co-limited except in regions where the mixed layer depth is relatively shallow.

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A common method used to evaluate road designs for bicycling is a survey of stated opinions based on imagined bicycling experiences that are used to represent real experiences. However, we know little about the connection between imagined and real bicycling experiences. In this study, we examine the relationship between bicyclists’ (first-person experienced) and video survey participants’ (imagined) ratings of bicycling comfort and safety. We do this with real-world bike rides/surveys ( n = 20) and a blocked experiment conducted through a web-based video survey of female undergraduates ( n = 1,203). We show that imagined ratings resemble first-person experienced ratings, but that they have a systematic negative bias (approximately 10% to 15%). This suggests that imagined bicycling experiences seem less comfortable and safe compared with real experiences. We compare both methodological and psychological explanations for this result and the consequent bicycling implications for each.

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