Low Deposition Results
Posted: August 4th, 2025, 12:14 pm
Good evening,
In order to validate my understanding of how to set up and use HYSPLIT for deposition modelling, I have been trying to run a test case for Fukushima just for deposited Cs-137.
However, I am experiencing an issue where my deposited Cs-137 seems magnitudes too low.
I have been using GDAS 0.5-deg in 3 hr intervals and used the emissions data from Tereda et al. (2012) using the EMITIMES file. It all seems to be working okay, from the period 11th - 22nd March the fallout pattern seems not inappropriate. (see files: FukushimaQGIS for GIS picture, FukushimaHYSPLIT for the contours produced by HYSPLIT directly) However, my maximum Bq/m^2 is 9.7E4 which is two orders of magnitude lower than the UNSCEAR maximum activity (see Fukushima UNSCEAR) at this time which is 2.8E6 Bq/m^2.
I'm not expecting it to be dead on the same, but I've tried to replicate everything I can and I'm at a loss as to why it's so different.
I'd really appreciate any insights as I've been going over this for two days and don't seem to be getting anywhere! Please let me know if there's any other info I could provide to support.
In order to validate my understanding of how to set up and use HYSPLIT for deposition modelling, I have been trying to run a test case for Fukushima just for deposited Cs-137.
However, I am experiencing an issue where my deposited Cs-137 seems magnitudes too low.
I have been using GDAS 0.5-deg in 3 hr intervals and used the emissions data from Tereda et al. (2012) using the EMITIMES file. It all seems to be working okay, from the period 11th - 22nd March the fallout pattern seems not inappropriate. (see files: FukushimaQGIS for GIS picture, FukushimaHYSPLIT for the contours produced by HYSPLIT directly) However, my maximum Bq/m^2 is 9.7E4 which is two orders of magnitude lower than the UNSCEAR maximum activity (see Fukushima UNSCEAR) at this time which is 2.8E6 Bq/m^2.
I'm not expecting it to be dead on the same, but I've tried to replicate everything I can and I'm at a loss as to why it's so different.
I'd really appreciate any insights as I've been going over this for two days and don't seem to be getting anywhere! Please let me know if there's any other info I could provide to support.