kris,
We DO have very accurate data; and not due to the nuclear industry.
The US national laboratories were on top of this from the beginning including mine.
https://str.llnl.gov/JanFeb12/sugiyama.html
Making Sense of a Tsunami of Data
During the early days of the crisis, data were scarce. The tsunami brought down power lines, and many stations were off-line. But within days, the floodgates of 21st century communications opened up. NARAC carried out calculations based on information from a multitude of sourcesweather and monitoring stations in Japan, the DOE teams deployed to Japan, other national laboratories, NRC, and a plethora of Web sites and e-mail streams, many of which had to be translated and checked for accuracy.
Once in Japan, DOEs Aerial Measuring System and ground-monitoring teams began to send large volumes of valuable data to CMHT, as did Japanese organizations. Soon, NARAC was flooded with an abundance of riches. Having to process, quality assure, and analyze all the data so they could be used in support of modeling efforts was a major challenge, says Sugiyama.
It is either a MYTH or DOWNRIGHT LIE from the anti-nukes that there was no data, or that the data was made up by the nuclear industry.
We have had to inform people like Rosen of their ERROR in saying that there was no data, or that the results are less than what would be expected. These other people like Rosen are the one's that are going with "made up" or "approximated" data. The actual results from the actual measurements of what was released, is much, much milder than that hypothesized by people like Rosen. Besides, Rosen is part of an anti-nuclear advocacy group; how "objective" do you really think they are?
I know you don't like it; but we DO have very accurate data on what was released and the radiation effects thereof.
PamW