About HPAC

Dennis Garrity is a systems agronomist and research leader whose career has focused on improving small-scale farming systems in the tropics. He has been serving as Drylands Ambassador for the UN Convention to Combat Desertification, emphasizing the role of agroforestry, evergreen agriculture and landcare for sustainable land management. From 2001 to 2011, he served as Director General of the World Agroforestry Centre. He is currently Chair of the Board of the Global EverGreening Alliance, a partnership of nearly all of the major development and conservation organizations around the world, working together to restore hundreds of millions of hectares of degraded land and enhance the livelihoods of millions of the least-favored smallholder farm families in the tropics. He also chaired Landcare International from 2005 to 2020, a worldwide effort to support grassroots community-based natural resource management, and currently is a member of the Board of Global Landcare. Dennis is HPAC Outreach Coordinator. 

Herb Simmens has been a city manager, county administrator, chief planner for the state of New Jersey, and on the faculty of two universities. He is the author of A Climate Vocabulary of the Future. He holds degrees from the Wharton School of the University of Pennsylvania and the School of Public and International Affairs of Princeton University, and also studied at the London School of Economics. He lives in Silver Spring, Maryland. Herb is HPAC Co-Founder and Organizational Coordinator. 

Rebecca has extensive experience in agency performance management, financial advice, governance and relationship management.  She advised on the resourcing of two major system reforms in a 10 year period, in the child protection and family services portfolio.  In her community work, she has worked with small organizations including supporting the establishment of two housing cooperatives, with multicultural membership. Rebecca has three degrees from the University of New South Wales: BComm (Hons), major in Economics, an MA in Women’s Studies and an MBA. Rebecca has been a member of HPAC for two years and was introduced by Robert Tulip, a university friend.  She is also an active member of Rebrighten.org, which highlights nature-based approaches to increasing planetary brightness and thereby cooling the planet, alongside emissions reduction and removal of excess greenhouse gases from the atmosphere. 

Ron Baiman is a retired Associate Professor of Economics at Benedictine University in Lisle, IL. He a founding member of the Chicago Political Economy Group (CPEG) where preprints of his latest papers (published in the Review of Radical Political Economy) including: “Our Two Climate Crises Challenge” (2022), “In Support of a Renewable Energy and Materials Economy” (2021) “Financial Bailout Spending Would Have Almost Paid for Thirty Years of Global Green New Deal Climate: Triage, Regeneration, and Mitigation” (2020), can be found. Ron Baiman holds a Ph.D., and an M.A. with Honors, both in Economics from the New School for Social Research in New York City, did graduate work in Mathematics at the U.C. Berkeley, and graduated Magna Cum Laude with a B.Sc. in Mathematics and Physics from Hebrew University, Israel. Ron is HPAC Co-Founder and Convening Coordinator. 

Michael MacCracken has been serving on a pro bono basis as Chief Scientist for Climate Change Programs with the Climate Institute since his retirement in 2002. An alum of Princeton (B.S.E., 1964) and the University of California Davis (Ph.D., 1968), he led climate change studies at the Department of Energy's Lawrence Livermore National Laboratory from 1968-93 and then served as senior scientist with the interagency Office of the U.S. Global Change Research Program from 1993-2002 and successively as the executive director of the Office from 1993-97 and executive director of the first US national assessment coordination office from 1997-2001. From 2003-07, he served as president of the International Association of Meteorology and Atmospheric Sciences. 

Bruce Melton PE is a professional engineer, environmental researcher, filmmaker, climate science education specialist, author, and director of the Climate Change Now Initiative founded in 2005. He has written over 600 reviews of academic climate science, and has recently been involved in ground breaking climate policy development where he was awarded a special achievement award by Sierra Club for helping in the establishment of new climate restoration policy and a safer limit to warming of "less than 1.0 degrees C above normal," that reverses or stabilizes already initiated ecological collapse and climate tipping activation, and restores extreme weather mayhem back to its former rare levels. He travels North America seeking climate change impacts and his recent award-winning film project, Climate Change Across America, can be seen at ClimateDiscovery.org, (https://www.climatediscovery.org/) along with his counterintuitively beautiful climate change photography at ClimateChangePhoto.org (https://climatechangephoto.org).

Dr. Brian von Herzen is the founder and Executive Director of the Climate Foundation, an organization focused on developing nature-based global food security solutions and associated regeneration of ecosystem services and measuring carbon export of these regenerative processes in seas and soils.  Over the past few years, the Climate Foundation has pioneered the development of XPRIZE-winning Marine Permaculture deepwater irrigation systems to restore natural upwelling, kelp forests, coral reefs and seaweed forests, regenerating fisheries and the ocean’s ability to fix carbon scalably. Brian has a PhD from Caltech in planetary sciences and engineering, and a Physics degree, magna cum laude, from Princeton University. An inventor with over 30 patents issued, he is applying three decades experience designing systems to develop a chip in Silicon Valley to be used with regenerative Marine Permaculture vessels. 

Robert Tulip has a Master of Arts Honours Degree from Macquarie University in ontology and ethics and a Graduate Diploma in Foreign Affairs and Trade from Monash University.  He worked for thirty years in the Australian Public Service in international development, including policy and program management across a number of different sectors and countries, especially in Papua New Guinea.  He has been working in climate engineering since 2007, when his work on forests and climate led him to see large scale ocean-based algae production as a decisive technology for climate stability.