Details

Autor(en) / Beteiligte

• Dolan, Brenda
• Kollias, Pavlos
• Heever, Susan C.
• Rasmussen, Kristen L.
• Oue, Mariko
• Luke, Edward
• Lamer, Katia
• Treserras, Bernat P.
• Haddad, Ziad
• Stephens, Graeme
• Chandrasekar, V.

Titel

Time Resolved Reflectivity Measurements of Convective Clouds

Ist Teil von

• Geophysical research letters, 2023-11, Vol.50 (22), p.n/a

Ort / Verlag

Washington: John Wiley & Sons, Inc

Erscheinungsjahr

2023

Quelle

Wiley Online Library Journals Frontfile Complete

Beschreibungen/Notizen

• National Aeronautics and Space Administration's Investigations of Convective Updrafts (INCUS) mission aims to document convective mass flux through changes in the radar reflectivity (ΔZ) in convective cores captured by a constellation of three Ka‐band radars sampling the same convective cells over intervals of 30, 90, and 120 s. Here, high spatiotemporal resolution observations of convective cores from surface‐based radars that use agile sampling techniques are used to evaluate aspects of the INCUS measurement approach using real observations. Analysis of several convective cells confirms that large coherent ΔZ structure with measurable signal (>5 dB) can occur in less than 30 s and are correlated with underlying convective motions. The analysis indicates that the INCUS mission radar footprint and along track sampling are adequate to capture most of the desirable ΔZ signals. This unique demonstration of reflectivity time‐lapse provides the framework for estimating convective mass flux independent from Doppler techniques with future radar observations. Plain Language Summary The vertical transport of water between Earth's surface and the upper troposphere afforded by convective storms is a driving factor of weather and climate. However, observing dynamic processes at the scales of convection has been a challenge due to the transient and rapidly evolving nature of convection, as well as sensor and resource limitations. High‐resolution time‐lapses of radar reflectivity are used to investigate the movement of air and water within deep, intense storms. This is a unique approach to understanding how water and air move throughout the atmosphere in strong storms. It is shown that large changes in reflectivity are apparent even over time scales less than 30 s, which are inferred to be due to strong vertical motions. A new National Aeronautics and Space Administration satellite mission called Investigations of Convective Updrafts seeks to use the same methods to estimate the movement of air and water globally across the tropics. Key Points Convective motions can cause measurable ΔZ changes in time intervals as short as 30 s The reflectivity time‐lapse rate technique relates to spatially and temporally coherent structures and the underlying convective motions The Investigations of Convective Updrafts mission radar sampling characteristics are adequate for capturing most of the ΔZ changes caused by convective motions