In a new study published in Nature Climate Change, Clem and colleagues reported that the South Pole has experienced a record-high warming of 1.81 ± 1.02°C during the last 30 years, three times larger than the global average. They used observational records to show that the recent warming of the South Pole, which started around 2000 following... Continue Reading →
The climate model simulations forced with increasing anthropogenic greenhouse gases consistently project a robust decline of the Atlantic Meridional Overturning Circulation (MOC) and a strengthening of the Southern Hemisphere westerly winds, which may in turn result in an increase in the Southern Ocean MOC. In a research article recently accepted in the Journal of Physical... Continue Reading →
Observations from Argo floats and satellite shows that the rate of global ocean warming during 2005-2015 is largely consistent with the climate simulations under the increasing greenhouse gas concentration. However, during that period, the southern hemisphere oceans have absorbed up to 98% of the net global ocean heat gain, while the warming of northern hemisphere... Continue Reading →
Under the high emission scenario for the future (RCP 8.5), a nearly ice-free Arctic Ocean (i.e., sea-ice extent less than 10-6 km2 for at least five consecutive years) in northern summer is likely before 2050. A decrease in Antarctic sea-ice extent is also expected during the 21st century, but at a slower rate with large uncertainty.... Continue Reading →
A study published in Nature Geoscience (Bronselaer et al., 2020) analyzed new observations from autonomous floats with ocean-biogeochemical sensors (Bio-Argo) along with historical shipboard ocean measurements to document changes in Southern Ocean physical and ocean-biogeochemical variables (i.e., temperature, salinity, pH, concentrations of nitrate, dissolved inorganic carbon and oxygen) during the last two decades. Due to... Continue Reading →
Atmospheric blocking over the high-latitude North Atlantic blocks the westerly jet stream, causing the eastward propagation of weather systems to stall for 7 days or so. An earlier study by Häkkinen et al. (2011) used the 20th century atmospheric reanalysis product of NOAA (20CR) to show that the wintertime blocking frequency over high latitude North Atlantic covaries... Continue Reading →
The lower limb of the Global Meridional Overturning Circulation (GMOC) is supplied by the sinking of the heavy water mass that forms around the Antarctica, known as the Antarctic Bottom Water (AABW). Repeat hydrographic data along the Atlantic, Pacific and Indian Ocean sections observed during the mid 1990s, 2000s and 2010s indicate that the volume... Continue Reading →
According to Redfield stoichiometry, marine organisms incorporate and release PO4 and Dissolved Inorganic Carbon (DIC) in a relatively fixed proportion. Additionally, PO4 in the ocean is not affected by air-sea exchange. Therefore, PO4 and DIC in the ocean can be used to estimate biology-driven versus air-sea flux-driven oceanic DIC redistributions. Applying this method to sediment core data, a new paper... Continue Reading →
The surface water in the South Atlantic (σ2 < 35.7) is known to originate largely from the Indian Ocean via the Agulhas leakage (e.g., Beal et al., 2011; Gordon, 1986). It is carried northward below the surface mixed layer and brought to the surface via the equatorial Atlantic upwelling. Antarctic Intermediate Water (AAIW) that forms... Continue Reading →
The Little Ice Age (LIA) is a period of cold global average surface temperatures from around 1600 to 1850, following the Medieval Warm Period (950 ~ 1250). A new study published in Science suggested that since the ocean adjusts to the surface thermal anomalies with the time scales of 100 ~ 1,000 years, some parts of the... Continue Reading →
Ocean to Climate 