Climate Research
Arctic Sea Ice Melt
One of the surest signs that our climate is rapidly changing.
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Current Research
The Influence of High Frequency Forcing on Ocean Processes
Short time-scale perturbations of the wind and temperature fields due to storms, cold air outbreaks, polar lows and topographically induced flows are known to enhance air-sea heat fluxes, but their relative contribution to ocean mixing and circulation is not well understood. To understand better how these high frequency forcings influence climate, I filtered short time-scale perturbations from the wind and temperature fields and showed that they generated episodic fluctuations in the Atlantic Meridional Overturning Circulation and in the strength of the sub-polar gyre (Holdsworth and Myers 2015).
Weather patterns are shifting in the rapidly changing Arctic climate system. Wind bursts and storms influence
oceanic conditions through upwelling and entrainment as well as altering the fluxes of heat and gases at the air-sea-ice interface. By examining the transports through all of the Arctic and sub-arctic straits I showed that these winds can influence the volume and freshwater transport out of the Arctic which may have an impact on the large scale North Atlantic overturning system.
Weather patterns are shifting in the rapidly changing Arctic climate system. Wind bursts and storms influence
oceanic conditions through upwelling and entrainment as well as altering the fluxes of heat and gases at the air-sea-ice interface. By examining the transports through all of the Arctic and sub-arctic straits I showed that these winds can influence the volume and freshwater transport out of the Arctic which may have an impact on the large scale North Atlantic overturning system.
Understanding and predicting the stable atmospheric boundary layer
Most parameterizations of turbulence in the stable boundary layer are based on empirical fits to atmospheric data
and do not accurately represent the physical processes that influence the strength of the near surface temperature
inversion. As a result, numerical weather prediction and climate models can exhibit unrealistic runaway cooling in
very stable conditions. To systematically evaluate the relative influence of the physical controls on the near surface
temperature inversion and winds, I developed idealized models of the stable boundary layer. Although the basic
equations are non-linear, they are simple enough that they can be linearized and examined with a dynamical systems
approach (Holdsworth, Rees and Monahan 2016). I have since extended the model to include a horizontal pressure
gradient, Coriolis effects and a simple surface radiative scheme.
and do not accurately represent the physical processes that influence the strength of the near surface temperature
inversion. As a result, numerical weather prediction and climate models can exhibit unrealistic runaway cooling in
very stable conditions. To systematically evaluate the relative influence of the physical controls on the near surface
temperature inversion and winds, I developed idealized models of the stable boundary layer. Although the basic
equations are non-linear, they are simple enough that they can be linearized and examined with a dynamical systems
approach (Holdsworth, Rees and Monahan 2016). I have since extended the model to include a horizontal pressure
gradient, Coriolis effects and a simple surface radiative scheme.
Projecting Oceanic Conditions Under Future Climate Warming Scenarios
I am currently developing high resolution models of the Arctic and Northern Pacific oceans that includes ice and biogeochemical cycling. These models will be used to make projections of habitat change under future climate warming scenarios and this information will be used by collaborators to make projections for higher trophic level species.
