Publication Date:
2019-07-17
Description:
The vertical structure of the atmospheric boundary layer (ABL), simulated with the
mesoscale modelWeather Research and Forecasting (WRF) as well as with its polar
optimized version Polar WRF, was compared to tethered balloon soundings and
mast observations taken in March and April 2009 from two Arctic fjords in Svalbard.
From twelve short (48 h) simulations, the Quasi-Normal Scale Elimination scheme
for the ABL and the NOAH land surface scheme for the surface were found to
perform best and were selected for one long (16 day) simulation. The differences
in performance of the standard WRF and Polar WRF were marginal. A warm
bias, especially near the surface, was found in the modelled temperature profiles
related to underestimated temperature inversion strength and depth. The modelled
humidity inversions were generally deeper but weaker than the observed, and often
occurred independently of temperature inversions. The largest errors in temperature
and humidity occurred under high pressure conditions. Multiple temperature and
humidity inversions were usually not captured byWRF. Compared to the compact
sea ice east of Svalbard, the modelled temperature and humidity inversions were
weaker and less frequent over the fjords. The biases in modelled wind speed profiles
were closely related to low-level jets (LLJs); the modelled LLJs were stronger and
deeper, and typically located at higher altitudes than the observed LLJs. Errors in the
near-surface variables were notably reduced by applying post-processing equations
based on othermodelled variables.
Repository Name:
EPIC Alfred Wegener Institut
Type:
Article
,
isiRev
Format:
application/pdf
Permalink