The Northeast Pacific coastal ocean, as a typical river-influenced coastal upwelling system, is characterized by significant variability of sea surface partial pressure of carbon dioxide (</span><i><spa...The Northeast Pacific coastal ocean, as a typical river-influenced coastal upwelling system, is characterized by significant variability of sea surface partial pressure of carbon dioxide (</span><i><span style="font-family:Verdana;">p</span></i><span style="font-family:Verdana;">CO</span><sub><span style="font-family:Verdana;">2</span></sub><span style="font-family:Verdana;">, <200 to >1000</span></span><span style="font-family:""> </span><span style="font-family:""><span style="font-family:Verdana;">μ</span><span><span style="font-family:Verdana;">atm). This study reviewed the </span><a name="_Hlk76571454"></a><i><span style="font-family:Verdana;">p</span></i><span style="font-family:Verdana;">CO</span><sub><span style="font-family:Verdana;">2</span></sub><span style="font-family:Verdana;"> variability and its underlying controlling mechanism in this highly dynamic region by bringing together previous scientific findings and historical data. The large </span><i><span style="font-family:Verdana;">p</span></i><span style="font-family:Verdana;">CO</span><sub><span style="font-family:Verdana;">2</span></sub><span style="font-family:Verdana;"> variability reflects the complex interactions between physical processes (riverine input and coastal upwelling) and the biological </span><span style="font-family:Verdana;">responses to the nutrient transportation associated with these physical</span><span style="font-family:Verdana;"> processes, while temperature and air-sea gas exchange play a minor role in affecting </span><i><span style="font-family:Verdana;">p</span></i><span style="font-family:Verdana;">CO</span><sub><span style="font-family:Verdana;">2</span></sub><span style="font-family:Verdana;">. Both the river water and upwelled subsurface water are characterized by higher concentrations of </span><i><span style="font-family:Verdana;">p</span></i><span style="font-family:Verdana;">CO</span><sub><span style="font-family:Verdana;">2</span></sub><span style="font-family:Verdana;"> and nutrients when compared to the coastal surface water. The presence of high chlorophyll-a and low </span><i><span style="font-family:Verdana;">p</span></i><span style="font-family:Verdana;">CO</span><sub><span style="font-family:Verdana;">2</span></sub><span style="font-family:Verdana;"> in river plumes and areas adjacent to upwelling locations showed the intense biological CO</span><sub><span style="font-family:Verdana;">2</span></sub><span style="font-family:Verdana;"> uptake. The influences of riverine input and coastal upwelling thus mainly depend on the competing effect of high background </span><i><span style="font-family:Verdana;">p</span></i><span style="font-family:Verdana;">CO</span><sub><span style="font-family:Verdana;">2</span></sub><span style="font-family:Verdana;"> of river water and upwelled subsurface water vs. the biological dropdown of </span><i><span style="font-family:Verdana;">p</span></i><span style="font-family:Verdana;">CO</span><sub><span style="font-family:Verdana;">2</span></sub><span style="font-family:Verdana;"> resulting from the riverine- and upwelling-associated nutrient supplies. The strength of upwelling-favorable wind plays an important role in the </span><i><span style="font-family:Verdana;">p</span></i><span style="font-family:Verdana;">CO</span><sub><span style="font-family:Verdana;">2</span></sub><span style="font-family:Verdana;"> variability by affecting the intensity of coastal upwelling, with stronger wind speed causing more intense upwelling. The long-term </span><i><span style="font-family:Verdana;">p</span></i><span style="font-family:Verdana;">CO</span><sub><span style="font-family:Verdana;">2</span></sub><span style="font-family:Verdana;"> increasing rate in the Northeast Pacific coast is observed to be lower than that in the North Pacific open ocean.展开更多
文摘The Northeast Pacific coastal ocean, as a typical river-influenced coastal upwelling system, is characterized by significant variability of sea surface partial pressure of carbon dioxide (</span><i><span style="font-family:Verdana;">p</span></i><span style="font-family:Verdana;">CO</span><sub><span style="font-family:Verdana;">2</span></sub><span style="font-family:Verdana;">, <200 to >1000</span></span><span style="font-family:""> </span><span style="font-family:""><span style="font-family:Verdana;">μ</span><span><span style="font-family:Verdana;">atm). This study reviewed the </span><a name="_Hlk76571454"></a><i><span style="font-family:Verdana;">p</span></i><span style="font-family:Verdana;">CO</span><sub><span style="font-family:Verdana;">2</span></sub><span style="font-family:Verdana;"> variability and its underlying controlling mechanism in this highly dynamic region by bringing together previous scientific findings and historical data. The large </span><i><span style="font-family:Verdana;">p</span></i><span style="font-family:Verdana;">CO</span><sub><span style="font-family:Verdana;">2</span></sub><span style="font-family:Verdana;"> variability reflects the complex interactions between physical processes (riverine input and coastal upwelling) and the biological </span><span style="font-family:Verdana;">responses to the nutrient transportation associated with these physical</span><span style="font-family:Verdana;"> processes, while temperature and air-sea gas exchange play a minor role in affecting </span><i><span style="font-family:Verdana;">p</span></i><span style="font-family:Verdana;">CO</span><sub><span style="font-family:Verdana;">2</span></sub><span style="font-family:Verdana;">. Both the river water and upwelled subsurface water are characterized by higher concentrations of </span><i><span style="font-family:Verdana;">p</span></i><span style="font-family:Verdana;">CO</span><sub><span style="font-family:Verdana;">2</span></sub><span style="font-family:Verdana;"> and nutrients when compared to the coastal surface water. The presence of high chlorophyll-a and low </span><i><span style="font-family:Verdana;">p</span></i><span style="font-family:Verdana;">CO</span><sub><span style="font-family:Verdana;">2</span></sub><span style="font-family:Verdana;"> in river plumes and areas adjacent to upwelling locations showed the intense biological CO</span><sub><span style="font-family:Verdana;">2</span></sub><span style="font-family:Verdana;"> uptake. The influences of riverine input and coastal upwelling thus mainly depend on the competing effect of high background </span><i><span style="font-family:Verdana;">p</span></i><span style="font-family:Verdana;">CO</span><sub><span style="font-family:Verdana;">2</span></sub><span style="font-family:Verdana;"> of river water and upwelled subsurface water vs. the biological dropdown of </span><i><span style="font-family:Verdana;">p</span></i><span style="font-family:Verdana;">CO</span><sub><span style="font-family:Verdana;">2</span></sub><span style="font-family:Verdana;"> resulting from the riverine- and upwelling-associated nutrient supplies. The strength of upwelling-favorable wind plays an important role in the </span><i><span style="font-family:Verdana;">p</span></i><span style="font-family:Verdana;">CO</span><sub><span style="font-family:Verdana;">2</span></sub><span style="font-family:Verdana;"> variability by affecting the intensity of coastal upwelling, with stronger wind speed causing more intense upwelling. The long-term </span><i><span style="font-family:Verdana;">p</span></i><span style="font-family:Verdana;">CO</span><sub><span style="font-family:Verdana;">2</span></sub><span style="font-family:Verdana;"> increasing rate in the Northeast Pacific coast is observed to be lower than that in the North Pacific open ocean.