Phys.org August 29, 2023 A team of researchers in the US (Stevens Institute of Technology, NOAA) evaluated spatiotemporal variability of deterministic and probabilistic precipitation nowcasting models’ performance over the greater New York City area. They assessed five deterministic and two probabilistic nowcasting methods using Multi-Radar Multi-Sensor data from 2014 to 2022. Three lead times of 2, 4 and 6 h were considered. LINDA-P had the best average Pearson’s correlation of 0.87 at the first step and 0.47 at the last one and the longest 80 min average decorrelation times. Its Mean Absolute Error (MAE) was four times lower in winter […]
Tag Archives: Weather forecasting
Can rainbows monitor the environment?
Nanowerk July 31, 2023 Surface enhanced Raman scattering (SERS) is becoming a highly topical technique for identifying and fingerprinting molecules. Crucial for SERS is the need for substrates with strong and reproducible enhancements of the Raman signal over large areas and with a low fabrication cost. An international team of researchers (UK, Germany, the Netherlands, Belgium) found that dense arrays of plasmonic nanohelices have excellent SERS properties. As an illustration, they presented two new ways to probe near-field enhancement generated with circular polarization at chiral metasurfaces, first using the Raman spectra of achiral molecules (crystal violet) and second using a […]
Extended-range forecasts to be recast in next model upgrade
Phys.org May 18, 2023 In the next upgrade of European Centre for ECMWF’s (Medium-Range Weather Forecasts) Integrated Forecasting System (IFS), extended-range forecasts will have 101 instead of 51 ensemble members and will run more frequently than before, at a consistent horizontal resolution of 36 km. The upgrade will lead to improvements in forecast performance across all parameters. The extended-range forecasts provide predictions up to 46 days ahead. The 51‑member ensemble in the current configuration cannot always properly capture small shifts in forecast probabilities. Doubling the ensemble size to 101 ensemble members will provide a more accurate representation of the forecast […]
Underused satellite, radar data may improve thunderstorm forecasts
Science Daily March 9, 2023 Many of the processes necessary for daytime convection initiation (CI) are rooted in the planetary boundary layer (PBL), which numerical models struggle to accurately predict. To improve ensemble forecasts of the PBL and subsequent CI forecasts in CAM ensembles, researchers at Pennsylvania State University explored the use of underused data from both the GOES-16 satellite and the national network of WSR-88D radars. The GOES-16 satellite provides observations of brightness temperature (BT) to better analyze cloud structures, while the WSR-88D radars provide PBL height estimates and clear-air radial wind velocity observations to better analyze PBL structures. […]
New weather prediction model produces more accurate typhoon intensity forecasts
Phys.org October 12, 2022 Researchers in China cycled and evaluated western North Pacific (WNP) typhoons of 2016 using Kalman filter (EnKF) combined with the Advanced Research Weather Research and Forecasting model (WRF). For all TC categories, the 6-h ensemble priors from the WRF/EnKF system had an appropriate amount of variance for TC tracks but had insufficient variance, they overestimated the intensity for weak storms but underestimated the intensity for strong storms. Comparison with the 5-d deterministic forecasts compared to the NCEP [US] and ECMWF [European] operational control forecasts showed that the WRF/EnKF forecasts generally had larger track errors than the […]
Scientists solve mystery of icy plumes that may foretell deadly supercell storms
Science Daily September 9, 2021 The strongest supercell thunderstorms typically feature an above-anvil cirrus plume (AACP), which is a plume of ice and water vapor in the lower stratosphere that occurs downwind of the ambient stratospheric flow in the lee of overshooting deep convection. AACP-origin hydration of the stratosphere has a poorly constrained role in ozone destruction and surface warming. A team of researchers in the US (Stanford University, University of Wisconsin) used large eddy simulations corroborated by radar observations to understand the physics of AACP generation. They showed that the overshooting top of a simulated supercell can act as […]
On calm days, sunlight warms the ocean surface and drives turbulence
Science Daily March 1, 2021 Over land, afternoon warming can lead to atmospheric convection and turbulence resulting in thunderstorms. Over the ocean, the afternoon convection also draws water vapor from the ocean surface to moisten the atmosphere and form clouds. The warming over the ocean is more subtle and gets stronger when the wind is weak. A team of researchers in the US (Oregon State University, NOAA Boulder Co) gathered lidar data around the clock for about two months. At one point, surface temperatures warmed each afternoon for four straight days with calm wind speeds, giving researchers the right conditions […]
5G wireless may lead to inaccurate weather forecasts
Rutgers University September 24, 2020 The signals from the 5G frequency bands potentially could leak into the band used by weather sensors on satellites that measure the amount of water vapor in the atmosphere and affect weather forecasting and predictions. Researchers at Rutgers University used computer modeling to examine the impact of 5G “leakage” on forecasting the deadly 2008 Super Tuesday Tornado Outbreak in the South and Midwest. Based on modeling, 5G leakage power of -15 to -20 decibel Watts affected the accuracy of forecasting of precipitation (by up to 0.9 millimeters) during the tornado outbreak and temperatures near ground […]
New lidar instruments peer skyward for clues on weather and climate
Phys.org May 21, 2019 There is a critical need for vertical measurement profiles of humidity, aerosols, and temperature in the lower troposphere to provide needed coverage for improved weather and climate forecasting across the U.S. There has been a gap in the instrumentation to meet this vision for research and monitoring without relying on aircraft-based devices. A team of researchers in the US (Montana State University, NCAR) has developed diode-based micro-pulse DIAL (MPD) technology as an economical route to a profiler that could make accurate measurements and fulfill desired specifications for continuous, unattended operation and eye safety. The technology will […]
Extreme rainfall events are connected around the world
Science Daily January 30, 2019 An international team of researchers (UK, Germany, Russia) developed a new method rooted in complex system theory to study high-resolution satellite data of rainfall. By breaking the globe into a grid, the team could see where events occurred and determine how ‘synchronous’ they were. The results from this ‘complex network’ model, analysed using their understanding of the motion of the atmosphere, revealed a possible mechanism for how the events were connected. The research could help better predict when and where extreme rainfall events will occur around the world. The insights can be used to test […]