Sea surface temperature variability in southern Okinawa Trough during last 2700 years

Abstract

Most of the temperature reconstructions for the past two millennia are based on proxy data from various sites on land. Here we present a bidecadal resolution record of sea surface temperature (SST) in Southern Okinawa Trough for the past ca. 2700 years by analyzing tetraether lipids of planktonic archaea in the ODP Hole 1202B, a site under the strong influence of Kuroshio Current and East Asian monsoon. The reconstructed SST anomalies generally coincided with previously reported late Holocene climate events, including the Roman Warm Period, Sui‐Tang dynasty Warm Period, Medieval Warm Period, Current Warm Period, Dark Age Cold Period and Little Ice Age. However, the Medieval Warm Period usually thought to be a historical analogue for the Current Warm Period has a mean SST of 0.6–0.8°C lower than that of the Roman Warm Period and Sui‐Tang dynasty Warm Period. Despite an increase since 1850 AD, the mean SST in the 20th century is still within the range of natural variability during the past 2700 years. A close correlation of SST in Southern Okinawa Trough with air temperature in East China, intensity of East Asian monsoon and the El‐Niño Southern Oscillation index has been attributed to the fluctuations in solar output and oceanic‐atmospheric circulation.

Coral‐Derived Western Pacific Tropical Sea Surface Temperatures During the Last Millennium

“…Our finding of warmer SSTs in the 20th/21st centuries and MCA period and cooler SSTs during the LIA is broadly consistent with other records from the western Pacific region. For example, SST during the MCA in the Southern Okinawa Trough (East China Sea) was 25.7°C, 0.4°C lower than that in the 20th century (Wu et al, ). Similarly, planktonic foraminiferal Mg/Ca‐SST records from the Makassar Strait (Indonesia) showed warm temperatures and high salinities occurred during the MCA, while the SSTs during the LIA were ~1.5°C cooler than present (Newton et al, ).…”

A comparison of the climates of the Medieval Climate Anomaly, Little Ice Age, and Current Warm Period reconstructed using coral records from the northern South China Sea

“…To better understand the present-day climate conditions and the potential trends of future climate change, it is necessary to extend the temporal scale of investigation into the last millennium [Jones et al, 1998;McGregor et al, 2015]. The last millennium includes three distinct climate intervals: the Medieval Climate Anomaly (MCA, AD 900-1300) [Lamb, 1965;Crowley and Lowery, 2000], the Little Ice Age (LIA, AD 1550-1850 [Robock, 1979;Bradley and Jones, 1993], and the Current Warm Period (CWP, AD 1850-present) [Wu et al, 2012;Fleury et al, 2015]. The MCA and LIA are climate anomalies that were caused by natural forcing (e.g., solar variability and volcanic emissions), but the CWP is linked to anthropogenic factors (e.g., industrialization and land-use changes) [Masson-Delmotte et al, 2013].…”

Sea surface temperature variation during the last deglaciation in the southern Okinawa Trough: Modulation of high latitude teleconnections and the Kuroshio Current

“…Over the last two decades, many studies have investigated SST in the OT using various proxies (e.g., Zhao et al, 2005;Ijiri et al, 2005;Zhou et al, 2007;Yu et al, 2009;Chen et al, 2010;Kubota et al, 2010;Wu et al, 2012). Records of SST based on U K' 37 from the southern OT revealed that warming during the last deglaciation was synchronous with ice volume changes, but lagged the warming in Greenland's ice core record and the terrestrial monsoon record (Zhao et al, 2005).…”

“…The southern OT is less sensitive to the influence of cold water than the northern OT and is more suitable for the use of multiple proxies for paleotemperature studies. So far, however, only a few reconstructions of SST exist in the southern OT (Zhao et al, 2005;Wu et al, 2012). This paper aims to use three temperature proxies (foraminiferal Mg/Ca, U K' 37 and ) to determine SST variations in the southern OT since the last deglaciation and to examine the response of regional SST to both Northern and Southern Hemisphere climate and local KC modulation.…”