From VoA reporter Steve Herman’s Twitter feed:

Austrian scientists have released what appears to be the first clear, independent data concerning radiation levels in the immediate aftermath of the Fukushima radiation leak.By releasing data from two monitoring stations of the Comprehensive Test Ban Treaty Organization CTBTO from Japan and California, researchers from the Central Institute for Meteorology and Geodynamics in Vienna have calculated backwards to estimate the true levels of radiation from Fukushima.

“The estimated source terms for iodine-131 are very constant, namely 1.3 x 10^17 becquerels per day for the first two days (US station) and 1.2 x 10^17 becquerels per day for the third day (Japan),” the institute said in a German-language statement posted on Wednesday on its website.

“For cesium-137 measurements, (the US station) measured 5 x 10^15 becquerels, close, while Japan had much more cesium in its air. On this day, we estimate a source term of about 4 x 10^16.”

A “becquerel” is the unit that measures how many radioactive nuclei decay per second, and the “source term” refers to the quantity and type of radioactive material released into an environment.

“The nuclear catastrophe at Chernobyl had a source term of iodine-131 at 1.76 x 10^18 becquerels of cesium-137 at 8.5 x 10^16 bequerels,” the statement added. “The estimated for Fukushima source terms are thus at 20 percent of Chernobyl for iodine, and 20-60 percent of Chernobyl for cesium.”

However, other scientists are not ready to put the Fukushima fallout into Chernobyl territory just yet.

“My speculation is that it’s going to be significantly less than Chernobyl fallout, but we’re not going to know that until we get more data,” said Jim Smith, an environmental physicist at the University of Portsmouth in the United Kingdom, in an interview with Deutsche Welle. “We’re not seeing data from the immediate 20 kilometer radius of the plant.”

Although the Fukushima accident is a disaster, it could have been worse. [Gerhard] Wotawa [the lead Austrian researcher] said it was fortunate that during the first two days of the accident, when radiation was leaking at a greater rate, there were constant winds out to the Pacific.

If the winds had been blowing towards Japan, it would have been much worse, he said.

via Austrian authorities release detailed data on Japan radiation | Science & Technology | Deutsche Welle | 23.03.2011.