Planned Weather Modification Research Articles

Sunset and Sunrise of the Illinois Weather Modification Act

Illinois, which had enacted a regulatory and monitoring act for planned weather modification activities in 1973, recently saw its model act sunset (repealed), as a part of a State’s sunsetting act for all lllinois regulatory activities. This paper describes the original Illinois Control Act, the process of sunsetting, and the subsequent reformulation of a new control act in lllinois. A review of the history of these sunsetting and then sunrise activities, as represented by the new 1981 Weather Modification Act in ~llinois, may help others facing similar sunsetting of regulatory activities, specifically those relating to weather modification, why the 1973 Weather Modification Control Act in lllinois, considered by many to be a model statute (Weather Modification Advisory Board, 1978) was revised, with parts eliminated, during the sunsetting and sunrising is discussed.

Atmospheric Sciences at the Illinois State Water Survey: Five Decades of Diverse Activities and Achievements

During a 50-yr history of diverse scientific endeavors, the Illinois State Water Survey's weather group has constantly shifted to meet new challenges as the nation's only sizable atmospheric research and services group housed in a state agency. The hundreds of projects encompass basic and applied research; data collection, evaluation, and storage; field projects; instrument design, development, and testing; and a services program in response to the needs of the public and specialized users of weather and climate information. Areas of major achievements include development of numerous meteorological instruments and data systems including the CHILL radar; participation in several national field projects, including the Metropolitan Meteorological Experiment (METROMEX); and pioneering research in radar meteorology, weather impacts, planned weather modification, inadvertent urban weather and climate change, applied climatology, and hydrometeorology.

Progress in planned weather modification research: 1991–1994

This quadrennial marked progress in understanding basic cloud processes under natural and seeded conditions, development of conceptual models, and application of advanced computer cloud models and instrumentation. Conceptual models were revised so that effects on the scale of cloud particles, precipitation processes, and cloud development no longer are artificially distinguished from one another; for example hail suppression and precipitation enhancements are now viewed as possible concurrent effects from seeding. Transport and dispersion studies using tracers have begun to show the path of seeding material and have allowed documentation of physical effects. Application of two‐ and three‐dimensional computer cloud models have helped to explain some results, to guide field operations, and to suggest further work. Instrumentation such as microwave radiometers and lidars have been used to document the spatial and temporal structure of supercooled liquid water.

Society's involvement in planned weather modification

Study of the societal and environmental aspects of planned weather modification have helped point to the issues and concerns that weather modification practitioners, state and federal officials, and supporters of weather modification programs must consider if the utilization of the precipitation modification technologies is to proceed in a meaningful way within our society. The understanding of these issues and how to address them is of particular importance in implementing and operating a state program. Social, economic, and legal impacts call for state involvement in project development, project funding, regulation and monitoring, research, and in public relations. The degree of state involvement varies according to the length of a project and the degree of certainty of the capability to enhance precipitation.

PURPOSEFUL AND ACCIDENTAL WEATHER MODIFICATION: OUR CURRENT UNDERSTANDING

The fields of planned and inadvertent weather are reviewed. The history, major problems, current scientific status, and research needs are assessed. Planned weather modification has been plagued by groups with conflicting interests and views, and most of the major U.S. experiments have failed owing to various problems. Basic research in cloud physics and dynamics is needed but the field now has the expertise and instrumentation to make major advances. Inadvertent weather modification studies have defined many of the urban influences but studies of regional-scale effects from irrigation and aircraft contrails need to be pursued. Studies are recommended to define better the social and environmental impacts from altered weather.

Atmospheric Issues Identified in State Water Resource Planning

Abstract Illinois is completing a comprehensive statewide water plan. The plan selects three atmospheric issues, among the 11 identified as key issues facing the state's water resources. The issues selected include climate change and prediction, inadvertent weather and climate modification, and planned weather modification. Each atmospheric issue presents major resource or policy problems, with capabilities needed to enhance the quality and/or quantity of the state's waters. The identification of these atmospheric issues reveals awareness at the policy level of their importance. Policy and programmatic needs found to be common to each issue include 1) collection of more data and continued research (with an increasing state role; 2) coordinated policy development around atmospheric expertise from several agencies and universities; and 3) an expanded public information program. A Climate Detection and Assistance Board is to be established in Illinois to provide the planning, coordination, and assistance nee...

Comments on “Planned Weather Modification and the Severe Weather Threat in the Central High Plains”

Comments on “Planned Weather Modification and the Severe Weather Threat in the Central High Plains”

Planned Weather Modification and the Severe Weather Threat in the Central High Plains

Operational and experimental convective cloud-seeding projects are often planned without regard to the number of seeding-opportunity days that can be lost because of the need to suspend operations during the threat of severe weather. June daily rainfall, severe storm and tornado watches, and observed tornadoes within a hypothetical (proposed) operational area over southwest Kansas were compared within the context of five procedures for severe weather related operations suspensions. These procedures varied in the restrictions placed on operations. The results show that anywhere from 45–87% of the June rain can fall when operations have been suspended. The length of a scientific seeding experiment could be increased anywhere from 45–426%. Finally, 46% of the tornadoes occurred when there were no concurrent tornado watches. This failure rate is so large that severe weather watches may not be useful for operations suspension procedures.

ACCIDENTAL AND PLANNED WEATHER MODIFICATION IN ILLINOIS1

ABSTRACT: Weather modification, both planned by man and that accidentally produced by man, has been under intensive study in Illinois for ten years. Most everyone in Illinois and the Midwest is living in a climate that now is modified inadvertently from its natural state. State atmospheric scientists have tackled weather modification through a series of interrelated studies beginning with climatic studies (to establish the background), experimental design studies, experimental field studies to verify changes and their causes, and finally socio‐economic and environmental studies to measure the impacts of weather modification. Studies at St. Louis show that the city acts as a trigger of summer clouds and rainfall leading to 4 to 6 summer days with 3 cm or more rain somewhere just east of the city. Power plants and jet aircraft also accidentally produce climatic changes. A focus on planned weather modification has been on the design of needed midwestern experiments in rainfall enhancement and hail suppression including the societal and environmental impacts.

The Public Decides about Weather Modification

Planned weather modification is a potentially significant phenomenon being introduced in many area of this and other countries. Evidence is beginning to accumulate suggesting that where organized resistance persists over a period of time, weather modification efforts are in fact halted. The paper briefly outlines the history of weather modification in the United States; research findings on the social aspects of weather modification (especially focused on acceptance/rejection processes); and decision processes, including legislative regulation and decision roles. Tentative social scientific evidence suggests that one condition of public acceptance of this technology is public involvement in the adoption decision process.

Urban effects on the distribution of heavy convective rainfall

Data from a network of 225 recording rain gages in 5500 km2, operated during the summers of 1971–1973 in the St. Louis area, were used to investigate potential urban effects upon the distribution of heavy rainfalls. The primary purpose was to determine quantitatively the effect of inadvertent weather modification upon the frequency and magnitude of short‐duration, intense rain rates that are pertinent to urban and suburban sewer design and of concern in applications of planned weather modification to alleviate agricultural and municipal water supply shortages. Emphasis was placed upon analysis of (1) rain cells, the basic convective unit responsible for the production of heavy short‐duration rates in thunderstorm‐dominated climates, such as the Midwest, and (2) the distribution of heavy rainstorms producing 25 mm or more of rainfall within the network. Comparison of urban‐affected and rural (nonaffected) rain cells was the primary evaluation tool in evaluating the urban effect. Results showed a substantially greater water yield from the urban‐affected cells compared with that from the rural (control) cells. The excess was greatest in moderate to heavy storms and apparently resulted most often from enhancement of the natural atmospheric rainfall processes in organized weather systems. The 25‐mm rainstorms showed a pronounced maximum of occurrence in a region that frequently lies downwind of two urban‐industrial areas, St. Louis and Alton‐Wood River. It was concluded that the frequency distribution of heavy rainfalls may vary significantly between urban, suburban, and rural areas in large urban‐industrial regions and that this may necessitate reevaluation of sewer design storm parameters in current use.

The Paradox of Planned Weather Modification

A paradox has developed involving on one hand sizeable reductions during the last two years in federal support of weather modification, as opposed to major scientific-technical advances in the field plus strong recommendations for increased federal support from the scientific community. The major recent advances include the capability to operationally dissipate cold fogs, to enhance snow from orographic clouds, and to increase rain from tropical clouds, plus the discovery of sizeable urban-related increases in rainfall. Other advances include special weather radars, aircraft with new cloud sensors and the capability to penetrate thunderstorms, new seeding materials and delivery systems, and new techniques for evaluation of projects. These have been coupled with the spread of weather modification around the world and with the initiation of major seeding projects in Colorado (NHRE, HIPLEX, and San Juan Project), Florida, South Dakota, and Illinois-Missouri (METROMEX). Several groups (NACOA, NAS, ICAS, NWC, AMS) all made a series of positive recommendations for advancing the field through more federal support and reorganization. Yet, beginning in FY74, federal support for weather modification dropped 21% when other R&D increased 11%. Many possible causes for the paradox appear, including fear of weather changes, lack of scientific commitment, and a series of public, scientific, political, and military controversies. The three basic issues are that weather modification is still an immature technology; the socio-economic impacts are ill defined; and its management has been uncertain. Proper resolution of the paradox is more apt to occur either because of a dramatic scientific breakthrough or from growing concerns about weather and climate-related environmental changes.

Social Aspects of Weather Modification

Abstract A description of the social context and citizen response to three weather modification projects provides an introduction to the discussion of a variety of social and economic issues related to planned weather modification. Various interest groups have markedly different perspectives on weather modification. Most persons subject to the consequences of weather modification have no opportunity to participate in the associated decision process even though they believe they have a right to do so. Factors possibly associated with conflict over weather modification are considered.

ATMOSPHERIC CONTROLS OF WATER EXCHANGE IN GREAT LAKES BASIN1

ABSTRACT Existing meteorological controls of water exchange by precipitation and evaporation on the Great Lakes are almost entirely inadvertent and related to man's urban‐industrial complexes and their effect upon precipitation processes. These inadvertent effects have led to 10 to 40% increases in precipitation in localized areas within the basin. Envisioned growth of urban‐industrial complexes within the Great Lakes region should lead to more inadvertent weather modification in the Basin. The only existing planned weather modification efforts are those at Lake Erie which are attempting to eliminate by redistribution the concentration of lake‐derived heavy snowfall along the south shore. It appears reasonable to assume that practical increases of lake precipitation on the order of 5‐20% could be achieved on an operational basis over the Great Lakes in the next 10 years, but the time of accomplishment will depend on national priorities, international cooperation, and economic factors. These activities would certainly produce a sizeable increase in the water quantity of the Great Lakes and should result in an improvement in water quality. Operational methods of evaporation suppression applicable to the lakes are just not available. Meteorological controls to ameliorate certain undesirable lake‐effect snowstorms are a near reality.

Recent studies of urban effects on precipitation in the United States

A review of recent research in the United States concerning urban effects on precipitation has revealed that relatively few studies have been performed. The lack of densely spaced precipitation stations with good historical records, inadequate instruments for airborne measurements of the mechanisms that affect precipitation systems, and the difficulties associated with separating orographic, maritime, and gage-exposure effects are the primary reasons for so little research. However, certain climatological studies of four variously sized cities in the midwest and two large cities in the east have shown apparent urban-produced increases ranging from 5 to 16% in annual precipitation and rain days, with 7 to 20% increases in summer thunderstorm days. Substantially greater increases in precipitation, thunderstorms, and hailfalls, 31 to 246%, have been shown in a recent study of an area downwind from a major steel mill complex. The available results show little evidence of urban effects on the occurrence of excessive rainfall rates or on the amount of snowfall, although little study of these conditions has been performed. The recent development of airborne nuclei measuring instruments has led to selected measurements of condensation and freezing nuclei over several urban areas. These furnish evidence that urban-induced nuclei concentrations are high and probably sufficient to produce the observed changes in precipitation, whereas other American studies have indirectly shown the importance of the urban thermal effects. The study of inadvertent precipitation increases from urban areas has particular significance for planned weather modification since the amounts of the inadvertent increases approximate those confirmed for planned experiments. The results of the urban studies may indicate the effectiveness of ground-based seeding, the possibility of successful increases in all seasons, the likelihood of thunderstorm and hailstorm increases with rainfall increases, and the need for dense raingage networks to adequately determine the area and amount of increase.