Comparison of ship-based CTD measurement of Circumpolar Deep Water in the Amundsen Sea based on World Ocean Database

We compare the characteristics of Circumpolar Deep Water (CDW) in the Amundsen Sea based on Conductivity-Temperature-Depth (CTD) records in the World Ocean Database. There are considerable numbers of ship-based CTD casts in the year 1994, 2000, 2007 and 2009. After confining temporal- and spatial- windows, several stations are emerged as having at-least two casts in different years. The comparisons show that the CDWs turn warmer and salter on shelf and near ice shelf. The results therefore describe the geographic differences of CDW changes, and exhibit rareness of ship-based CTD survey in the Amundsen Sea

Interannual variation of summer sea surface temperature in the Amundsen Sea, Antarctica

This paper investigates the interannual variability of January sea surface temperature (SST) in the Amundsen Sea (AS) during the period 1982–2022. SST in the Pine Island Bay (PIB) is found to exhibit the most significant interannual variation, with a standard deviation up to 0.6°. Composite analysis indicates that, in warmer years, the January SST at PIB is approximately 1° higher on average than that in cooler years, and its variation in warmer (cooler) years corresponds to lower (higher) sea ice concentration (SIC) and more (less) surface heat flux; the latter factor is primarily influenced by the albedo of SIC. Further analysis suggests that variability in January SIC is largely dominated by northward sea ice motion during the previous November (r = −0.82), which is consistent with the presence of a contemporaneous northerly 10 m wind anomaly trigged by the Amundsen Sea Low (ASL). The ASL-associated northerly wind anomaly drives northward sea ice motion, reduces SIC, and thus increases the downward heat flux that ultimately results in warmer SST, and vice versa. This study identifies the possible mechanism of anomalous January SST in the PIB, which could provide an important clue for seasonal forecasts of summer SST in the AS

LMS-SM3 and HSS-SM3: Instantiating Hash-based Post-Quantum Signature Schemes with SM3

We instantiate the hash-based post-quantum stateful signature schemes LMS and HSS described in RFC 8554 and NIST SP 800-208 with SM3, and report on the results of the preliminary performance test

XMSS-SM3 and MT-XMSS-SM3: Instantiating Extended Merkle Signature Schemes with SM3

We instantiate the hash-based post-quantum stateful signature schemes XMSS and its multi-tree version described in RFC 8391 and NIST SP 800-208 with SM3, and report on the results of the preliminary performance test

The change in blood glucose levels in tuberculosis patients before and during anti-tuberculosis treatment in China.

OBJECTIVE: We aimed to observe (i) changes in fasting blood glucose (FBG) in tuberculosis (TB) patients before and during anti-TB treatment, (ii) whether FBG levels were stable or unstable and (iii) baseline characteristics associated with an unstable FBG. METHOD: TB patients consecutively attended six clinics or hospitals. FBG measurements were made at months 0, 2 and 6. Data analysis was performed using the chi-square test and multivariate logistic regression. RESULTS: Of 232 patients without diabetes mellitus (DM) whose initial FBG < 6.1 mmol/L, over 90% maintained FBG < 6.1 mmol/L during treatment and no patient developed DM. Of 17 patients without DM and initial FBG between 6.1 and 6.9 mmol/L, over half had FBG < 6.1 mmol/L during treatment and no patient had DM at the end of treatment. Eight DM patients with already known DM had their FBG controlled at < 7.0 mmol/L during treatment. There were 13 DM patients newly diagnosed with FBG ≥ 7.0 mmol/L, and 69% continued to have FBG ≥ 7.0 mmol/L. After adjustment for confounding, the odds for an unstable FBG were higher for HIV-positive status, already having DM, smoking and coming to hospitals rather than clinics. CONCLUSION: TB patients who do not have DM based on FBG measurements do not develop DM during anti-TB treatment. Those newly diagnosed with DM on screening in general maintain their DM status with high FBG and need to be better managed

Overview of the MOSAiC expedition: Physical oceanography

Arctic Ocean properties and processes are highly relevant to the regional and global coupled climate system, yet still scarcely observed, especially in winter. Team OCEAN conducted a full year of physical oceanography observations as part of the Multidisciplinary drifting Observatory for the Study of the Arctic Climate (MOSAiC), a drift with the Arctic sea ice from October 2019 to September 2020. An international team designed and implemented the program to characterize the Arctic Ocean system in unprecedented detail, from the seafloor to the air-sea ice-ocean interface, from sub-mesoscales to pan-Arctic. The oceanographic measurements were coordinated with the other teams to explore the ocean physics and linkages to the climate and ecosystem. This paper introduces the major components of the physical oceanography program and complements the other team overviews of the MOSAiC observational program. Team OCEAN’s sampling strategy was designed around hydrographic ship-, ice- and autonomous platform-based measurements to improve the understanding of regional circulation and mixing processes. Measurements were carried out both routinely, with a regular schedule, and in response to storms or opening leads. Here we present alongdrift time series of hydrographic properties, allowing insights into the seasonal and regional evolution of the water column from winter in the Laptev Sea to early summer in Fram Strait: freshening of the surface, deepening of the mixed layer, increase in temperature and salinity of the Atlantic Water. We also highlight the presence of Canada Basin deep water intrusions and a surface meltwater layer in leads. MOSAiC most likely was the most comprehensive program ever conducted over the ice-covered Arctic Ocean. While data analysis and interpretation are ongoing, the acquired datasets will support a wide range of physical oceanography and multi-disciplinary research. They will provide a significant foundation for assessing and advancing modeling capabilities in the Arctic Ocean

Impact of Ross Gyre on surface circulation in the Amundsen Sea, Antarctica

The east limb of the Ross Gyre approaches the western Amundsen Sea, thereby exerting an influence on the surface circulation dynamics. This study investigates the impact of the zonal movement of the eastern boundary of the Ross Gyre on the surrounding surface geostrophic circulation in January. Specifically, a zonal shift of the eastern boundary of the Ross Gyre induces a substantial shelf-basin circulation within the Amundsen Sea. The findings of this study provide valuable insights into the influence of the Ross Gyre on the exchange processes between the Amundsen Sea shelf and basin

_{Data support for "Impact of Ross Gyre on surface circulation in the Amundsen Sea, Antarctica"}

time_series_rg_eb.txt: Time series of longitude of Ross Gyre Eastern Boundary in January during 1993--2020.postproc_timser_rossgyre_center.nc: Time series of Ross Gyre Centre, and low-pass sea surface height and geostrophic current.See more in https://iopscience.iop.org/article/10.1088/2515-7620/ad37f2.</p

Decadal variance of summer near-surface temperature maximum in Canada Basin of Arctic Ocean

In the summer Arctic, bump-like vertical temperature profiles of the upper layer in the Canada Basin suggest a near-surface temperature maximum (NSTM) beneath the mixed layer. This paper concentrates on describing the decadal variance of these NSTMs. Essentially, the temporal evolution of the summer NSTM revealed three decadal phases. The first period is before 2003, when the summer NSTM could rarely be observed except around the marginal of the Canada Basin. The second period is between 2003 and 2015, when the summer NSTM nearly occurred over the whole basin as accelerated decline of summer sea ice. The third period is from 2016 to 2017, when the summer NSTM almost disappeared due to prevailing warm surface water. Furthermore, for the background behind the decadal variance of summer NSTM, linear trends of the September minimum sea ice extent and surface water heat content in the Canada Basin from 2003 to 2017 were –2.75 ± 1.08 × 104 km2yr−1 and 2.29 ± 1.36 MJ m−2yr−1, respectively. According to a previous theory, if we assume that the trend of the summer surface water heat content was only contributed by NSTM, it would cause a decrease in sea ice thickness of approximately 13 cm. The analysis partially explains the reason for sea ice decline in recent years