This transect crosses the North Atlantic subpolar gyre near 60°N, in an area of large decadal change both for the gyre circulation and in temperature and salinity, which has increased since 1992 according to data from other observing systems in the region. During the same period, this region seems to have witnessed an increase of pCO2 larger than the atmospheric increase, suggesting a change in horizontal circulation, but also of vertical mixing. This is associated with large changes in the intermediate layer stratification that has increased through most of the period according to the XBTs and ARGO profiles. Surface fronts are prominent west of the Irminger Ridge, in the area of the Irminger Current, which feeds the western subpolar gyre where the Labrador (and occasional Irminger) intermediate waters are formed. The vertical structure of this current needs to be investigated to find whether it is changing as a result of the changes in vertical stratification and horizontal circulation that the region has encountered. ARGO floats will help shed some light on this, but their spatial coverage near the ridge is insufficient to resolve this variability. The missing observations are provided by XBTs.
For more information about the operation of this transect click here.
XBT deployments along AX02
AX02 Mean Temperature Section
The figure below shows the mean temperature section along AX02.
AX02 Temperature Standard Deviation
The figure below shows the standard deviation of the mean temperature section along AX02.
Temperature Space-Time Diagrams from AX02 XBT Profiles
The diagrams below show the temporal and spatial distribution of temperature along AX02 at selected depths.
*residuals are obtained by substracting the seasonal cycle