| DOI: | 10.5194/cp-10-1183-2014
|
| Scopus记录号: | 2-s2.0-84903462830
|
| 论文题名: | Impact of geomagnetic excursions on atmospheric chemistry and dynamics |
| 作者: | Suter I.; Zech R.; Anet J.G.; Peter T.
|
| 刊名: | Climate of the Past
|
| ISSN: | 18149324
|
| 出版年: | 2014
|
| 卷: | 10, 期:3 | | 起始页码: | 1183
|
| 结束页码: | 1194
|
| 语种: | 英语
|
| Scopus关键词: | atmospheric chemistry
; atmospheric dynamics
; climate modeling
; concentration (composition)
; geomagnetic field
; global climate
; heating
; hydrogen peroxide
; paleoclimate
; Quaternary
; stratosphere
; surface wind
; tropopause
; vortex
; westerly
; Antarctica
; Arctic
|
| 英文摘要: | Geomagnetic excursions, i.e. short periods in time with much weaker geomagnetic fields and substantial changes in the position of the geomagnetic pole, occurred repeatedly in the Earth's history, e.g. the Laschamp event about 41 kyr ago. Although the next such excursion is certain to come, little is known about the timing and possible consequences for the state of the atmosphere and the ecosystems. Here we use the global chemistry climate model SOCOL-MPIOM to simulate the effects of geomagnetic excursions on atmospheric ionization, chemistry and dynamics. Our simulations show significantly increased concentrations of nitrogen oxides (NOx) in the entire stratosphere, especially over Antarctica (+15%), due to enhanced ionization by galactic cosmic rays. Hydrogen oxides (HOx) are also produced in greater amounts (up to +40%) in the tropical and subtropical lower stratosphere, while their destruction by reactions with enhanced NOx prevails over the poles and in high altitudes (by ĝ̂'5%). Stratospheric ozone concentrations decrease globally above 20 km by 1-2% and at the northern hemispheric tropopause by up to 5% owing to the accelerated NOx-induced destruction. A 5% increase is found in the southern lower stratosphere and troposphere. In response to these changes in ozone and the concomitant changes in atmospheric heating rates, the Arctic vortex intensifies in boreal winter, while the Antarctic vortex weakens in austral winter and spring. Surface wind anomalies show significant intensification of the southern westerlies at their poleward edge during austral winter and a pronounced northward shift in spring. Major impacts on the global climate seem unlikely. © 2014 Author(s). |
| 资助项目: | SNSF, Swiss National Science Foundation
; SNSF, Swiss National Science Foundation
|
| Citation statistics: |
|
| 资源类型: | 期刊论文
|
| 标识符: | http://119.78.100.158/handle/2HF3EXSE/49255
|
| Appears in Collections: | 气候变化与战略
|
|
There are no files associated with this item.
|
| Recommended Citation: | |
Suter I.,Zech R.,Anet J.G.,et al. Impact of geomagnetic excursions on atmospheric chemistry and dynamics[J]. Climate of the Past,2014-01-01,10(3)
|
|
|