Record Details
Is Advection Important? An Examination of the Advective Dynamics of Sensible Heat and Their Influence on Subcanopy Carbon Fluxes in Heterogeneous Terrain
ScholarsArchive at Oregon State University
| Field | Value |
|---|---|
| Title | Is Advection Important? An Examination of the Advective Dynamics of Sensible Heat and Their Influence on Subcanopy Carbon Fluxes in Heterogeneous Terrain |
| Names |
Carrigg, Sean Stephen
(creator) Thomas, Christoph (advisor) |
| Date Issued | 2013-08-27 (iso8601) |
| Note | Bachelor of Science (BS) |
| Abstract | Abstract Understanding small-scale bio-atmospheric interactions is becoming increasingly important as the global climate continues to change at breakneck speed. A theoretical model of the sensible heat budget of a forest is developed combining conservation equations and concepts from fluid dynamics. Budget components are computationally evaluated using micrometeorological data taken during the period 27 August 2008 - 31 December 2009 within a mature Douglas fir (Pseudotsuga menziesii) forest site in the Coast Range of western Oregon, USA. The role of advection in the transfer of sensible heat is explored in the context of the surface energy balance and under conditions of varying turbulence strength. Horizontal variability of wind and temperature is analyzed following methods of Thomas (2011) to re-evaluate the common physical assumptions horizontal homogeneity, uniform gradients, and zero advection. Scalar similarity between sensible heat advection and advective carbon loss in the subcanopy due to vertical decoupling is explored under strong and weak advection conditions using concepts from Thomas et al (2013) and Thomas et al (2008). It was concluded that (1) advection plays a significant role in energy balance closure at nighttime when turbulent fluxes are small; (2) in general, total advection is non-zero (advective fluxes do not balance out); (3) it is invalid to assume horizontal homogeneity and uniform gradients in heterogeneous terrain; (4) advection tends to be greatest at intermediate values of turbulence strength (TKE or σw); and (5) there is a potential nonlinear relationship between advective carbon loss and sensible heat advection, particularly strong, horizontal advection. Approximate boundaries of tur28 bulence strength corresponding to regions of strong advection are shown in Table 1. Conclusion (5) provides the potential for analyzing biological carbon fluxes us30 ing purely physical variables and will be an interesting and necessary topic of future studies. |
| Genre | Thesis |
| Topic | Scalar similarity |
| Identifier | http://hdl.handle.net/1957/50654 |
