An Analysis of Climate Events in the Monterey Bay Based on the Extratropical Northern Oscillation Index (NOIx)

Abstract

The Monterey Bay National Marine Sanctuary (MBNMS) in the northeast Pacific (NEP) is linked to distant regions via the atmospheric Hadley-Walker (HW) circulation (Figure 1). Through these connections, the NEP is involved in a wide range of large-scale climate changes (e.g., El Nino and La Nina). These changes show up in the MBNMS as changes in sea level pressure (SLP), surface wind stress, precipitation, ocean temperature, upwelling, and other atmospheric and oceanic factors. The North Pacific High (NPH) is a major center in the atmospheric circulation. Variations in the NPH are a good indicator of the impacts of large scale climate change and the regional processes responsible for ocean anomalies in the MBNMS, since they are linked closely to the winds that drive the oceans. The Northern Oscillation Index (NOIx), based on the difference in SLP anomalies in the NPH and at Darwin, Australia, is well correlated with remote and local climate change events, including a wide range of upper ocean changes, in the MBNMS.