Notes on the Adirondack Blowdown of July 15Th, 1995
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Notes on the Adirondack Blowdown of July 15th, 1995 Scientific Background, Observations, and Policy Issues BY J ERRY JENKINS WORKING PAPER NO. 5 DECEMBER 1995 W IL D L IF E C O N S E R V A T IO N S O C IE T Y F O U N D E D IN 1 8 9 5 A S T H E N E W Y O R K Z O O L O G IC A L S O C IE T Y COVER PHOTO Liza Graham/Area in Adirondack Park affected by 1995 blowdown This summary report and position paper was prepared for the Wildlife Conservation Society by Jerry Jenkins, White Creek Field School, White Creek, New York 12057, (518) 686-7208. Foreword The Adirondack Blowdown of 1995 was a natural event at an exceptional scale. Just before dawn on the morning of July 15th, the sky exploded with thousands of lightning flashes at a rate of more than one per second. This dazzling display was the prelude to a broad wave of thunderstorms that crashed into the northwestern slope of New York's Adirondack mountains. The system proved to be a rare derecho, or straight-line storm of highly concentrated windbursts, at times surpassing 100 miles per hour. Less than an hour later, the sunrise would reveal that as many as half of all the trees in a forested area of nearly 100,000 acres were blown down, most with their crowns pointing to the southeast. Flying over the area with Jerry Jenkins, the author of this document, I was deeply humbled by this reminder of Nature's raw power. I had witnessed the effects of tornadoes in the Midwest and volcanoes in central Africa, but these paled in comparison with the scale of this storm. Perhaps because my 14 year-old son had been camping in the area when the storm hit, I was also struck by the fact that we normally judge such natural events in human terms of structures destroyed and lives lost; some of which sadly happened in the Adirondacks, too. But the devastation was nothing like it would have been had the storm struck in an area of even moderate human settlement. Instead, the Blowdown of '95 unleashed its greatest force in the midst of one of the world's largest forest reserves. The Adirondack Park covers more than six million acres, or 10,000 miles², of mountainous terrain in northeastern New York State. In the Oswegatchie River basin, where the storm's fury was concentrat4 mixed northern forest communities predominate over a landscape dotted with extensive wetlands and cut by a dense network of waterways. The region is further characterized by the unique mix of land ownership and land use patterns that is typical of the Adirondacks: publicly-held old-growth and functional old- growth forests, juxtaposed with active commercial forestry lands in private hands. The result is an exceptional opportunity to understand the effects of large-scale natural disturbance at an ecosystem scale, as well as the implications of such disturbance for future forest management under different land use practices. The Wildlife Conservation Society supports more than 260 projects in 53 countries around the world. These projects combine field research to understand complex problems with active conservation efforts to protect key ecosystems and wildlife populations. The most difficult of these projects focus on last-ditch efforts to maintain small relict habitats and populations. Where possible, it is far more efficient to work at the scale of larger ecosystems. Advantages include not only the presence of intact natural communities, but more flexible options to combine preservation with systems of sustainable use, in which management is guided by regular monitoring. Such sites also represent the last "living laboratories" where natural ecological processes, including disturbance, can be studied effectively. For all of these reasons, WCS supports work at dozens of large-scale forest sites around the world, from the Congo Basin to Papua New Guinea and from the Amazon to the Adirondacks. Notes on the Adirondack Blowdown of July 15th, 1995 contains a wealth of information about the origins, impacts, and implications of a major natural event in an ecosystem of global importance, all presented in an extremely accessible style by long-time Adirondack researcher Jerry Jenkins. The Wildlife Conservation Society is proud to have supported this effort and we hope that it proves helpful to all those interested in better understanding, managing, and protecting our natural forest heritage. Bill Weber Director, North America Program WCS Working Paper Series The Wildlife Conservation Society (formerly the New York Zoological Society and its field division, Wildlife Conservation International) has been dedicated to understanding and protecting the earth's wildlife and ecosystems since 1895. The Wildlife Conservation Society (WCS) has the largest field-based research staff of any international conservation organization, and currently operates more than 250 field projects in over 50 countries throughout Africa, Asia, Central America, South America, and North America. WCS scientists have conducted pioneering, long-term field studies; played direct roles in establishing over 100 national parks and reserves; trained conservation professionals in developing countries; helped to strengthen the local institutions in which they work; and contributed key ideas to on-going debates about resource management and conservation. The WCS Working Paper Series represents preliminary results of basic and applied field work supported by the Wildlife Conservation Society. The purpose of WCS Working Papers is to distribute project reports, benchmark data sets of historical significance, and other timely technical material in its entirety, and with as little delay as possible. Copyright: The contents of this paper are solely the property of the author, and cannot be reproduced without the permission of the author. WCS Working Papers Series Bleisch, William V. (1993) Management Recommendations for Fanjing Mountain Nature Reserve and Conservation of the Guizhou Golden Monkey & Biodiversity. WCS Working Paper No. 1 (38 pp.) Hart, John A. & Claude Sikubwabo (1994) Exploration of the Maiko National Park of Zaire, 1989-1994, History, Environment and the Distribution and Status of Large Mammals. WCS Working Paper No. 2 (88 pp.) Rumiz, Damian & Andrew Taber (1994) Un Relevamiento de Mamiferos y Algunas Aves Grandes de la Reserva de Vida Silvestre Rios Blanco y Negro, Bolivia: Situación Actual y Recomendaciones. WCS Working Paper No. 3 (40 pp.) (Spanish) Komar, Oliver & Nestor Herrera (1995) Avian Diversity at El Imposible National Park and San Marcelino Wildlife Refuge, El Salvador. WCS Working Paper No. 4 (76 pp.) (English and Spanish) Jenkins, Jerry (1995) Notes on the Adirondack Blowdown of July 15th, 1995: Scientific Background, Observations, and Policy Issues. WCS Working Paper No. 5 (93 pp.) Ferraro, Paul, Richard Tshombe, Robert Mwinyihali, and John A. Hart (1996) Projets Integres, de Conservation et de Developpement; Un Cadre pour Promouvoir la Conservation et la Gestion des Ressources Naturelles. WCS Working Paper No. 6 (105 pp.)(French) Harrison, Daniel J. & Chapin, Theodore G. (1997) An Assessment of Potential Habitat for Eastern Timber Wolves in the Northeastern United States and Connectivity with Occupied Habitat in Southeastern Canada. WCS Working Paper No. 7 (12 pp.) Hodgson, Angie (1997) Wolf Restoration in the Adirondacks? The Questions of Local Residents. WCS Working Paper No. 8 (85 pp.) Jenkins, Jerry (1997) Hardwood Regeneration Failure in the Adirondacks: Preliminary Studies of Incidence and Severity. WCS Working Paper No. 9 (59 pp.) Copies available from: Wildlife Conservation Society International Programs 2300 Southern Blvd. Bronx, NY 10460-1099 U.S.A. Tel: (718) 220-1442 Fax: (718) 364-4275 NOTES ON THE ADIRONDACK BLOWDOWN OF JULY 15TH, 1995: SCIENTIFIC BACKGROUND, OBSERVATIONS, AND POLICY ISSUES A summary report and position paper, prepared for the Wildlife Conservation Society by: Jerry Jenkins White Creek Field School White Creek, New York 12057 518 686 7208 December, 1995 Contents 1. Introduction ...............................................................................................................………. 1 2. Methods, Sources, Units .............................................................................................……… 5 3. Acknowledgements ...........................................................................................……………. 5 4. Maps....................................................................................………………………………… 7 1. General Areas of Moderate and Severe Damage 2. Swaths of Concentrated Damage 3. Public Lands in Main Damage Area 4. Blowdown in the Oswegatchie Basin - I 5. Blowdown in the Oswegatchie Basin - II 6. Areas Blown Down in 1950 and 1995 7. Blowdown Near Five Ponds 8. Northern Segment of Storm at 5:11 a.m. 9. Velocities in Radar Echo at 5:26 a.m. 10. Bow Echo at 5:46 a.m. 11. Two Maps of the 1950 Blowdown Near the Cold River 12. Current Blowdown and 1903, 1911 Fires 5. The Storm ......................................................................................................................…… 14 This storm has been variously called a derecho, a squall fine, a microburst, and a downburst. Which was it? What kinds of damage do derechos generate? What conditions led to the storm? How did the storm originate and what did it do? What was the structure of the storm? What was the storm like on the ground? What is known about the mechanism of such storms, and what is the source of the damaging winds? How well understood are such storms? Can derechos and microbursts be predicted? How strong