Mesoscale evaluation of AMPS using AWARE radar observations of a wind and precipitation event over the Ross Island region of Antarctica. (24th June 2022)

• Record Type: Journal Article
• Authors: Kingsmill, David E.; Seefeldt, Mark W.; Cassano, John J.
• Is Part Of: Quarterly journal of the Royal Meteorological Society. Volume 148:Number 747(2022)
• Page Start: 2607
• Page End: 2630
• Publication Date: 2022-06-24
• Subjects: AMPS -- Antarctica -- McMurdo Station -- mesoscale -- precipitation -- radar -- Ross Island -- wind; Meteorology -- Periodicals; 551.5
• DOI: 10.1002/qj.4327
• Languages: English
• ISSNs: 0035-9009

Abstract

Abstract: Surface, upper‐air, and radar observations are used to assess the performance of the Antarctic Mesoscale Prediction System (AMPS) in simulating the mesoscale aspects of a wind and precipitation event over the Ross Island region of Antarctica that spanned January 16–20, 2016. The observations, collected during the Atmospheric Radiation Measurement (ARM) West Antarctic Radiation Experiment (AWARE), provide a unique dataset for evaluating AMPS, especially the radar observations that facilitate a three‐dimensional depiction of winds and precipitation. Comparisons of AMPS forecast data with surface meteorology, balloon‐sounding, and profiling radar observations at and above sites near McMurdo Station reveal a mixture of similarities and differences. A generally southerly flow is evident at low levels in both the AMPS simulations and observed Doppler radial velocities. AMPS winds are comparable to those observed at the surface and aloft in terms of magnitude, direction, and timing but the strongest simulated southerly flow is displaced eastward relative to the observations. AMPS‐simulated reflectivity over the broader Ross Island region is more limited in areal extent and smaller in magnitude than observed by a scanning Doppler radar. Three episodes of surface precipitation are observed near McMurdo Station over the five‐day event with peak rates of ∼3 mm h −1 and a total accumulation of ∼22 mm. However, AMPS produces no surface precipitation at that location over the five‐day event due to a low‐level dry bias in the forecasts. The results show the first observationally based three‐dimensional understanding of meteorology in the Ross Island region. Abstract : Surface, upper‐air, and radar observations are used to assess the ability of the Antarctic Mesoscale Prediction System (AMPS) to simulate the mesoscale aspects of a wind and precipitation event over the Ross Island region of Antarctica in the period January 16–20, 2016. The observations, collected during the Atmospheric Radiation Measurement (ARM) West Antarctic Radiation Experiment (AWARE), provide a unique dataset for the evaluation of AMPS, especially the radar observations, which facilitate the three‐dimensional analysis of wind and precipitation.