The meridional overturning circulation (MOC) is my main research topic. Due to its enormous northward heat transport it is a key element for understanding the past, present and future climate evolution. Palaeodata indicate that the MOC may have undergone major changes in the past (e.g., last glacial period, transition from the last glacial period to the following warm period (Holocene)). Furthermore, many studies indicate that changes are likely to occur as a result of increasing greenhouse forcing.
I am particularly interested in the variability of the meridional overturning circulation (MOC) on subannual to interannual timescales. Since April 2004 the RAPID-MOCHA observing system has provided a continuous timeseries of the Atlantic MOC at 26N. The observations show that the MOC can exhibit large fluctuations on timescales as short as weeks to months ( see RAPID-MOC webpage). The nature of this variability and to what extent it reflects local or remote processes is far from fully understood yet. As a numerical modeller I'm using using ocean general circulation models (e.g. OCCAM an eddy-permitting ocean general circulation model) in order to highlight processes that may explain the observed MOC variability.
The vast number of observations available today mean that current changes in the climate can be observed in almost real time. My main interest here is concerned with the impact the increase in global temperatures by about 0.7C since the 1960s has had on a regional scale and how good/bad numerical models are at reproducing the observed changes. I am also studying the atmospheric circulation patterns that coincided with prolonged postive and negative temperature anomalies.