热液系统输向大洋的热通量估算

从四个方面对现代海底热液活动输向大洋的热通量进行了初步估算.热液系统通过集中、高温的热液烟囱和低温、大面积漫溢热水的形式向海洋输送的热通量为357GW;由底热异常边界层计算出的热通量为32GW;根据Baker提出的扩张洋脊的扩张速率和扩张洋脊热液柱覆盖率之间的线性关系,推算的热液通量为1086GW;根据扩张洋脊岩墙冷却和扩张推算的热通量为592GW.不同的方法给出的结果有较大的差异.一方面这些结果反映了热液系统向大洋的供热水平,另一方面反映了目前对现代海底热液活动的认识水平.虽然热液系统向大洋的热输出比太阳的热辐射小,但由于其特殊的供热方式,这部分热能仍有可能对全球气候带来影响,应在今后的研究中给予重视.

Heat flux estimates from hydrothermal system to the ocean

Four methods are used to estimate the heat flux from the hydrothermal system to the ocean.The heat flux from high temperature vents and low temperature warm water diffusion fields is about 357 GW.The heat flux from bottom thermal boundary layer is 32 GW.Based on Baker's linear relationship between spreading rate and plume incidence,the possibly total hydrothermal fields on the whole world ocean are calculated and then their heat flux estimate is about 1 086 GW.Based on the spreading axiscrust cooling model the result is about 592 GW.From the results it can be seen that the heat flux from the hydrot hermal system to the world ocean may be tens to thousands giga-watt on one hand,and on the other hand it is well known that it is not easy to estimate it actually now.The great differ ence comes mainly from limited knowledge about the distribution of the hydrothermal fields on the world ocean.The abovementioned analysis is shown that though the heat flux from the hydrothermal system to the ocean is much smaller than the heat flux from the solar radiation to the ocean,but concerning the different ways of supplying the world ocean with heat,much attention should be paid to the effects of the hydrothermal activity on the world ocean current and world climate.