Longtime Yankees catcher Yogi Berra once famously said that "half of baseball is 90% mental." For the IVARS crew, an equivalent malapropism would be that half of filtering water is 90% labeling.
Why is labeling so important? First, clear and logical labeling helps facilitate the often hectic and intricate task of shipboard water filtering. Because ship time is so precious, oceanographers attempt to fit as much sampling as possible into each cruise. Data analysis can wait for the laboratory back home. To maximize onboard data collection, we have to work quickly for many long hours, often with little sleep. A well-conceived labeling scheme lets us work more rapidly and efficiently, and helps minimize mental errors caused by drowsiness.
Quick work not only multiplies the number of samples we can collect, but also exposes samples to laboratory conditions for a shorter time before they're preserved. The goal of our sampling is to capture a "snapshot" of ocean temperature, biology, and chemistry with each sample. Thus we want to keep the water samples as close as possible to 28° F (their temperature when brought onboard), handle them in the dark to prevent any further photosynthesis by phytoplankton, and wear nitrile gloves to prevent contamination. Once the samples are processed, they are either frozen at 80° C or dried in an oven to help lock in their original characteristics.
Accurate labeling also ensures that we can place the samples in their proper context once we've shipped them back to the laboratory at VIMS. Each sample has to be exactly labeled as to its date, cruise number, location (latitude and longitude), station number, depth, data parameter, filter size, and any unusual characteristics (spills do happen, especially on a rolling ship!). To appreciate why accurate labeling is so critical, recall that we collect 12 pairs of Niskin bottles full of seawater from 12 different depths at each of the 24 IVARS stations, sample 7 different parameters for each dozen bottle pairs, and run some samples through as many as 3 different filter sizes. This has been going on now for the first four years of the IVARS project, with two cruises per year. Any particular sample might not be analyzed for weeks or months after its arrival at VIMS, and may well be analyzed by someone other than the person who prepared it. Thus accurate and compete labeling is an absolute must.
Many of the big questions of biological oceanography can only be answered by studying innumerable tiny filters and the organisms and compounds they've captured. If those filters aren't properly labeled, the big questions will remain unanswered, or even worse, be confounded by erroneous data.