Cloud Microphysical Observations of Relevance to the Texas Cold-Cloud Conceptual Seeding Model
AbstractThree pairs of seeded and non-seeded supercoled convective clouds, obtained in west Texas during August 1995, are studied because of their relevance to the cold-cloud conceptual seeding model that is guiding randomized seeding experimentation in this region. In comparing seeded and non-seeded clouds without supercooled rain drops on the initial pass, seeding appeared to result in: 1) graupel growth that was too slow to convert cloud water into precipitable size particles during the lifetime of the updraft, except for the most vigorous and vertically developed clouds, 2) a glaciation rate that was too slow for enhancement of the updraft and 3) glaciation during the collapse of the cloud which accelerated its dissipation, leaving holes in the cloud field. In contrast, in clouds with supecooled rain drops on the initial pass, seeding appeared to result in: 1) fast freezing of the supercooled rain drops and their continued growth as graupel, 2) enhanced growth of the grapuel as comared to supercooled rain drops in accordance with theoretical considerations and 3) rapid glaciation within the updraft, which increased cloud buoyancy and invigorated the updraft, providing a mechanism for the support of the growing graupel particles. Considering the small sample, these results are tentative. This research effort is continuing.
Authors that submit papers for publication agree to the Journal’s copyright and publication terms. Authors retain copyright and grant the journal right of first publication with the work simultaneously licensed under a Creative Commons Attribution License that allows others to share the work with an acknowledgement of the manuscript’s authorship and initial publication in Journal of Weather Modification. Authors are able to enter into separate, additional contractual arrangements for the non-exclusive distribution of the journal’s published version of the work (e.g., post it to an institutional repository or publish it in a book), with an acknowledgement of its initial publication in the Journal of Weather Modification. Authors are permitted to post their work online (e.g., in institutional repositories or on their website) prior to and during the submission process to encourage productive exchanges and greater citation of the published article.
Articles are published online using restricted access for the first year. After the first year, articles are made freely available online. Immediate open access for an article may be obtained by the author paying an open access fee which is in addition to the normal page changes. Authors are expected to honor a page charge in order to support publication and distribution of the journal. After the author approves the gallery formatted version for publication, the Weather Modification Association’s Secretary will invoice the corresponding author for the page charges and payment is due within 30 days.