First-ever daily time series of the strength of the abyssal MOC cell in the South Atlantic
Kersalé, Meinen, and coauthors investigate the MOC flows at the southern end of the South Atlantic Ocean to evaluate the variability of the oceanic circulation across 34.5°S in the South Atlantic at all depths and at a daily frequency. This research highlights the first-ever daily quantification of the time-varying strength of the abyssal cell at 34.5°S, for which prior studies had only produced once-a-decade "snapshot" ship section estimates.
US precipitation modulated by MJO-ENSO teleconnection interference
Subseasonal to seasonal climate forecasts in the US depends heavily on atmospheric and oceanic conditions in the tropical Indian and Pacific Ocean regions. While ENSO dominates seasonal predictability, the primary source of global predictability on subseasonal timescales is the MJO. To understand how ENSO and MJO interact, the authors isolated both MJO and ENSO signals and found that depending on the simultaneous location of the MJO convection and the background state of ENSO, the two signals can either enhance or mask each other.
Saildrone: Adaptively sampling the marine environment
To improve atmospheric and oceanographic monitoring, a new type of autonomous marine vehicle, the Saildrone, has been developed and deployed in over 40 cruises from which data are publicly available. Coupled with data from other sources such as satellites, Saildrone measurements could be useful for future algorithm and numerical model improvements, particularly at the fine spatial scale and in complex and previously data-sparse ocean regions.
Large Ensemble model simulations help to better quantify sources of uncertainty in climate projections
A new collection of single model initial-condition large ensembles (SMILEs) can test statistical assumptions with a cleaner separation between sources of uncertainty in climate projections. In particular, the potential bias at regional scales or for variables with a lot of internal variability can be greatly reduced.
Elevated storm surge differs in origin along the US East and Gulf Coasts
Yin and coauthors use the new GFDL CM4 and CM4HR models to consider a series of climate change experiments under the CMIP6 protocol to study characteristics of extreme sea level events and their future evolution in a fully coupled weather, climate, sea level, and storm surge modeling system. They found that even in the absence of global warming, the Gulf Coast is most vulnerable to hurricane-induced storm surge.
Density compensation minimizes the impact of the Labrador Sea convection to the AMOC
Zou and coauthors analyzed the transport and property fields across the Labrador Sea using OSNAP observations and an ocean reanalysis dataset GloSea5 to study why recent observations revealed minimal contribution of the Labrador Sea convection to the subpolar AMOC strength. They found that the density compensation has important consequences on the strength of the overturning circulation.
