A Feb. 14, 1995, Eos article, “Debate Over Free Exchange of Data Roils Geophysical World,” discussed a controversial proposal to develop a three-tiered system for meteorological data exchange. In response to the call for related Forum pieces, I offer the following comments.

Environmental data does not come cheap. The real costs of environmental data are frequently “buried” in the budgets of the multipurpose infrastructures that gather the information. Costs include instrumentation and calibration, siting and access, technical support, and data processing. Many producers and consumers probably do not know the actual “cost per information unit.” Smart systems, with communications links, are reducing acquisition costs; but the trend is countered by increasingly sophisticated and costly sensor technology and acquisition schemes.