R/V Ronald H. Brown Daily Summaries

Daily Summary July 17, 2002, DOY = 198

During the day the ship worked its way around Cape Cod and up the coast of Massachusetts arriving in Massachusetts Bay, just off Boston Harbor at midnight. The weather was clear over the entire period with winds from the WNW during the early part of the transit. The wind direction changed to the SW around noon as the ship was rounding the Cape, just as had been forecast by the study's team of crack meteorologists. The air was generally clean during the transit, becoming progressively more polluted as the ship approached the Boston area.

At this point in the cruise an interesting trend has been noted in the composition of fine particles. Sub micron particles of apparent anthropogenic origin are found to be considerably more acidic than larger particles from the same sources. In contrast, particles sampled from air that originated in clean marine regions showed much smaller differences in acidity as a function of size. This result is confirmed by both the bulk aerosol measurements and the aerosol mass spectrometer.

The DOE G-1 made a close approach to the ship in the early afternoon flying at an altitude of one hundred feet.

For all plots, time is indicated in GMT. Eastern time is -5 hours.

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Location
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Temperature, Pressure
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Sea Surface Temperature, Relative Humidity
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True Wind Speed, Direction
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Ship Speed, Direction
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Relative Wind Speed, Direction

Textual information and data plots are for quicklook and overview purposes only.