| Budget Amount *help |
¥4,810,000 (Direct Cost: ¥3,700,000、Indirect Cost: ¥1,110,000)
Fiscal Year 2017: ¥1,170,000 (Direct Cost: ¥900,000、Indirect Cost: ¥270,000)
Fiscal Year 2016: ¥1,560,000 (Direct Cost: ¥1,200,000、Indirect Cost: ¥360,000)
Fiscal Year 2015: ¥2,080,000 (Direct Cost: ¥1,600,000、Indirect Cost: ¥480,000)
|
|---|
| Outline of Final Research Achievements |
We have studied long-term/short-term geomagnetic secular variation using numerical models of MHD dynamo. Concerning thickness of a stably stratified layer beneath the core-mantle boundary, a thinner stably stratified layer is preferred to that with seismically inferred thickness, because strong attenuation of the magnetic field intensity and its secular variation through the layer is observed in numerical models. Parameter values of a paleosecular variation model derived from dynamo models show a trend similar to paleomagnetic data in spite of difference in its absolute values. The results suggest a common core dynamics in both numerical dynamos and the geodynamo determining a long-term trend such as polarity reversal frequency.
|
