How well do counts add up?

摘要

In many cities throughout the world, pollen counts are provided to the general public, often on a daily basis. This information is supplied by physicians in private clinics, hospital officials, university researchers, public health officials, and others and can be used by atopic individuals for planning daily activities or making decision about prophylactic medication. Generally, the count is based on the pollen and spore composition of the atmosphere during the previous 24 hours. In addition to pollen counts, a number of researchers now provide pollen forecasts based on historical pollen data for that location and current meteoro-logic conditions.Pollen counts are not absolute values but an estimate of the exposure for the area. It is known that the atmospheric pollen concentration is influenced by a number of variables, such as location of the sampler, sampler efficiency, prevailing winds, and other meteorologic conditions. Also, the distribution of pollen in the atmosphere is not homogeneous, and significant differences in concentration could be found from side-by-side samplers