Mean monthly climatological mixed layer depth (MLD) combined with temperature, dissolved oxygen, and apparent oxygen utilization (AOU) are used to produce global estimates of the seasonal variability of ocean heat content anomaly (OHCA), O2 content anomaly (O2CA), and AOU content anomaly (ACA) in the surface mixed layer. Linear regression analyses show that the highest correlation occurs when O2CA lags OHCA by one month, whereas the highest correlation occurs when ACA lags OHCA by 2-3 months. The O2CA is negatively correlated, while the ACA is positively correlated with the OHCA in the mixed layer. The O2-heat ratio in the surface mixed layer is about -1.85 nmol/J in the subtropical and subpolar regions, which is on the same order of magnitude due to the O2 solubility effect alone. The solubility effect is the primary driver for the seasonal cycle of the O2 inventory in the mixed layer, and thus subject to changes in ocean warming. The 1-month lag between O2CA and OHCA suggests the O2 inventory quickly responds to heat content changes on seasonal time scales due to strong mixing in the mixed layer. The 2-3 month lag between ACA and OHCA suggests oxygen changes through biological activities take a longer time following OHC changes in relation to physical changes through O2 solubility. Our analysis indicates that the deoxygenation rate in the mixed layer, estimated from the regression analysis, is approximately -2.2 Tmol/year based on the O2-heat ratio in the mid-latitudes, accounting for 6±2% of the global deoxygenation for the time period 1955-2019.

Marine microplastics (< 5 mm) pollution is a growing problem affecting coastal communities, marine ecosystems, marine life and human health. Microplastics have been detected throughout the entire global ocean, and it is hard to escape news of microplastics debris in our oceans. Despite the growing awareness, the management of marine microplastics data, from large-scale surveys along the coast and open ocean, to effects of microplastics on planktonic communities, lags far behind the needs of the scientific, education, and decision maker communities. The lack of large-scale, long-term comprehensive data on microplastics makes it difficult to completely understand the sources, distribution and impacts of microplastics, as well as forecasting their trajectory and aggregation under current and future climates. The National Oceanic and Atmospheric Administration’s (NOAA) National Centers for Environmental Information (NCEI), which is regarded as the nation’s environmental data steward, is spearheading efforts to create a global database on microplastics. As a first step, we are currently collating microplastics data from across the world into a primary marine debris data warehouse. The ultimate goal is to develop a one-stop repository where data on all types of microplastics are aggregated, archived, and served to the community in a consistent and reliable manner. Together with other NCEI databases, such as the Global Ocean Current Database, World Ocean Database, and the Surface Underway Marine Database, stakeholders will be able to access and assess data for their needs, thereby enhancing our capacity to understand and manage the problem of microplastics pollution. The microplastics database will be freely accessible and maintained with newly received data from global stakeholders.