Tsunami from asteroid impact
Dec. 27th, 2004 03:29 pm![[personal profile]](https://www.dreamwidth.org/img/silk/identity/user.png){kind=small}
mmcirvinGiven yesterday's horrific tsunamis and the concurrent interest in the possible impact of asteroid 2004 MN4 in 2029 (one chance in 37), this subject is going to get a lot of attention.
2004 MN4 is too small to destroy civilization, though it would be a pretty significant bang: an energy yield 30 times as large as the biggest bomb ever exploded, considerably bigger than Krakatoa, and about as big as the Tambora eruption of 1815 that caused "the year without a summer" of 1816 (and terrible tsunamis). Any populated area that 2004 MN4 hit would be pretty effectively erased (but there would be decades' worth of advance warning); aside from the possibility of global climatic effects, one question is whether it would be capable of doing more widespread damage through tsunamis.
Surprisingly to me, according to this interesting Australian Spaceguard page, some scientists think that it would not, except locally; the tsunamis might not be as powerful as yesterday's, because of the lower efficiency of energy conversion to coherent ocean waves. There would still be some serious trouble if it hit a hundred kilometers from a populated coast. 2004 MN4 is estimated to be somewhere in between this paper's "200m" and "500m" scenarios. Others estimate worse waves, and the issue seems to be somewhat contentious.
The page also has links to a lot of other interesting stuff, including information on the apparently obscenely overhyped threat of "mega-tsunami" from a volcano collapse in the Canary Islands.
2004 MN4 is too small to destroy civilization, though it would be a pretty significant bang: an energy yield 30 times as large as the biggest bomb ever exploded, considerably bigger than Krakatoa, and about as big as the Tambora eruption of 1815 that caused "the year without a summer" of 1816 (and terrible tsunamis). Any populated area that 2004 MN4 hit would be pretty effectively erased (but there would be decades' worth of advance warning); aside from the possibility of global climatic effects, one question is whether it would be capable of doing more widespread damage through tsunamis.
Surprisingly to me, according to this interesting Australian Spaceguard page, some scientists think that it would not, except locally; the tsunamis might not be as powerful as yesterday's, because of the lower efficiency of energy conversion to coherent ocean waves. There would still be some serious trouble if it hit a hundred kilometers from a populated coast. 2004 MN4 is estimated to be somewhere in between this paper's "200m" and "500m" scenarios. Others estimate worse waves, and the issue seems to be somewhat contentious.
The page also has links to a lot of other interesting stuff, including information on the apparently obscenely overhyped threat of "mega-tsunami" from a volcano collapse in the Canary Islands.