Sensitivity of orographic precipitation enhancement to horizontal resolution in the operational Met Office Weather forecasts

Smith, Samantha; Vosper, Simon; Field, Paul R.

doi:10.1002/met.1352

Cited by 40 publications

(41 citation statements)

References 27 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…While a deficiency in the mascon product cannot be ruled out, given the important role played by orography in driving the precipitation over the peninsula (van de Berg & Medley, 2016) and the sensitivity of orographic precipitation to horizontal resolution (e.g., Genthon et al, 2009;Smith et al, 2015), a plausible explanation is that the limited ability of the relatively coarse-resolution models to resolve the features and dynamics of the Antarctic Peninsula leads them to underestimate the true accumulation during EN15. The estimates fail to agree even within their error bars.…”

Section: Concluding Discussionmentioning

confidence: 99%

The Impact of the Extreme 2015–2016 El Niño on the Mass Balance of the Antarctic Ice Sheet

Bodart

Bingham

2019

Geophysical Research Letters

View full text Add to dashboard Cite

Interannual variations associated with El Niño-Southern Oscillation can alter the surface-pressure distribution and moisture transport over Antarctica, potentially affecting the contribution of the Antarctic ice sheet to sea level. Here, we combine satellite gravimetry with auxiliary atmospheric data sets to investigate interannual ice-mass changes during the extreme 2015-2016 El Niño. Enhanced precipitation during this event contributed positively to the mass of the Antarctic Peninsula and West Antarctic ice sheets, with the mass gain on the peninsula being unprecedented within GRACE's observational record. Over the coastal basins of East Antarctica, the precipitation-driven mass loss observed in recent years was arrested, with pronounced accumulation over Terre Adélie dominating this response. Little change was observed over Central Antarctica where, after a brief pause, enhanced mass-loss due to weakened precipitation continued. Overall, precipitation changes over this period were sufficient to temporarily offset Antarctica's usual (approximately 0.4 mm yr −1 ) contribution to global mean sea level rise.Plain Language Summary Given that the Antarctic Ice Sheet has the potential to raise sea level by over 50 m if completely melted, it is crucial that we fully understand the factors controlling its stability. Presently, changes in rates of mass loss and mass gain over the ice sheet vary from short (seasonal/ interannual) to long (decadal) timescales. Previous research has shown that one potential factor influencing Antarctica on interannual timescales is the El Niño-Southern Oscillation, a large-scale interaction between the Pacific Ocean and the overlying atmosphere that fluctuates between warm (El Niño) and cold (La Niña) states every 2-7 years. Here, we show an unprecedented increase in accumulation over the Antarctic Peninsula and West Antarctic sectors during the extreme 2015-2016 El Niño, along with a brief stabilization in mass loss over East Antarctica. Overall, precipitation changes during this event were sufficient to temporarily offset Antarctica's usual (approximately 0.4 mm yr −1 ) contribution to global mean sea level rise.As the dominant and most far-reaching mode of interannual climate variability, the impact of ENSO on the AIS is of particular interest. El Niño's influence in the Southern Hemisphere's high latitudes has been associated with blocking events induced by Rossby wave trains that alter surface-pressure distribution and

show abstract

Section: Concluding Discussionmentioning

confidence: 99%

The Impact of the Extreme 2015–2016 El Niño on the Mass Balance of the Antarctic Ice Sheet

Bodart

Bingham

2019

Geophysical Research Letters

View full text Add to dashboard Cite

show abstract

“…Precipitation occurrence and amount are among the hardest to predict, especially in mountainous terrain and summer [67] [68]. Here precipitation data are also the hardest to interpolate as gauges are often at low elevation and precipitation increases with height [69].…”

Section: Precipitationsmentioning

confidence: 99%

“…Consequently, the orographically forced lifting was weaker in the model than real world. This well known model artifact leads to systematic errors in simulated precipitation [67].…”

Section: Precipitationsmentioning

confidence: 99%

Assessment of the 2006-2012 Climatological Fields and Mesoscale Features from Regional Downscaling of CESM Data by WRF-Chem over Southeast Alaska

Mölders¹,

Bruyère²,

Gende³

et al. 2014

ACS

View full text Add to dashboard Cite

This case study examined how well downscaling of Community Earth System Model (CESM) data can reproduce climatological conditions relevant for summer (JJA) air quality in Glacier Bay National Park. Climatology was determined from the meteorological results obtained by the Weather Research and Forecasting model inline coupled with chemistry (WRF-chem) when driven with CESM data of 2006-2012. The climatology of this experiment (EXP) was evaluated by climatology from gridded blended sea-wind speeds, CRU data, and 42 surface meteorology sites. The quality relative to known performance was assessed by comparison to climatology determined from WRF-chem control simulations driven with FNL analysis data (CON) in forecast mode. Compared to observations, the thermodynamic and dynamic performances of EXP showed similar shortcomings (dampened diurnal temperature range, overestimation of wind speed over land) as CON. Over water EXP wind-speed climatology JJA bias (simulated minus observed) was −0.7 m/s. With respect to the CRU data EXP biases in JJA 2m temperature, diurnal temperature range, relative humidity and accumulated precipitation were −1.1 K, −4.9 K, 13%, and 110 mm, respectively. The slightly warmer atmosphere in EXP compensated for deficiencies in the cloud schemes leading to better results for the number of wet days and accumulated precipitation than in CON. Downscaling captured known mesoscale responses important for regional climate in a similar way as CON. When using CESM forcing, lateral boundary effects expanded spatially farther into the domain N. Mölders et al. 590 than known for forcing by analysis data. Overall, climatologies obtained from downscaling for Southeast Alaska had similar skill than those derived from forecasts driven by analysis data.

show abstract

“…Further, a number of studies analyse the effect of domain size and horizontal resolution (which is related to convection and cloud microphysics parametrization) on precipitation forecast skill in different numerical atmospheric models (e.g. Zängl, , ; Colin et al ., ; Güttler et al ., ; Smith et al ., ). Convection parametrization plays an important role at coarse resolutions (e.g.…”

Section: Introductionmentioning

confidence: 99%

Forecasts of extreme precipitation in the western Balkans in May 2014: model skill and sensitivity to the vertical co‐ordinate

Marjanović

Veljovic

Zaric

2017

Meteorological Applications

View full text Add to dashboard Cite

This study examines the simulation of the catastrophic precipitating event that occurred on 14–16 May 2014 over the western Balkans, using two regional models, the Eta model and the Weather Research and Forecasting Non‐hydrostatic Mesoscale Model (WRF‐NMM). This case was an extreme precipitation event with very large precipitation totals exceeding 200 mm in 72 h. The Eta model was run in two variants, switched to use the eta co‐ordinate with sloping steps and switched to use the sigma co‐ordinate. The aim of this study was to analyse the ability of the regional model to forecast heavy precipitation successfully as well as the impact of the vertical co‐ordinate on the forecasting of extreme precipitation events based on realistic model simulation. Experiments show the ability of regional models to reproduce extreme accumulations for 2 days of heavy precipitation with bias adjusted equitable threat score ranging from 0.3 to 0.5 for precipitation greater than the analysed threshold values (25–55 mm day−1), whereby the Eta model exhibits a slight advantage over the WRF‐NMM and the run of the Eta model switched to the eta co‐ordinate has the smallest frequency bias. For larger observed accumulations exceeding 50 mm day−1 all forecasts tend to be more biased. The root mean square precipitation difference varies insignificantly between the three forecasts. The results of the experiment indicate that, in the case of the extreme precipitation considered in this study, scores of the forecasts of the Eta model for 10 m wind speed and 2 m temperature show a small dependence on the vertical co‐ordinate and in favour of the run with the eta co‐ordinate.

show abstract

Sensitivity of orographic precipitation enhancement to horizontal resolution in the operational Met Office Weather forecasts

Cited by 40 publications

References 27 publications

The Impact of the Extreme 2015–2016 El Niño on the Mass Balance of the Antarctic Ice Sheet

The Impact of the Extreme 2015–2016 El Niño on the Mass Balance of the Antarctic Ice Sheet

Assessment of the 2006-2012 Climatological Fields and Mesoscale Features from Regional Downscaling of CESM Data by WRF-Chem over Southeast Alaska

Forecasts of extreme precipitation in the western Balkans in May 2014: model skill and sensitivity to the vertical co‐ordinate

Contact Info

Product

Resources

About