Four main lines of evidence support attribution of recent climate change to human activities: Firstly, a physical understanding of the climate system: greenhouse gas concentrations have increased and their warming properties are well-established. Secondly, there are historical estimates of past climate changes suggest that the recent changes in global surface temperature are unusual. Thirdly, computer-based climate models are unable to replicate the observed warming unless human greenhouse gas emissions are included. And finally, natural forces alone cannot explain the observed warming.
There is a strong scientific consensus that the Earth has been consistently warming since the start of the Industrial Revolution, and the rate of recent warming is largely unprecedented. This warming is mainly caused by the rapid increase in atmospheric carbon dioxide (CO2) since 1750 from human activities such as fossil fuel combustion, cement production, and land use changes such as deforestation, with a significant supporting role from the other greenhouse gases such as methane and nitrous oxide. This human role in climate change is now considered "unequivocal" and "incontrovertible".
The American Geophysical Union (AGU) is a 501(c)(3) nonprofit organization of Earth, atmospheric, ocean, hydrologic, space, and planetary scientists and enthusiasts that according to their website includes 130,000 people. AGU's activities are focused on the organization and dissemination of scientific information in the interdisciplinary and international fields within the Earth and space sciences. The geophysical sciences involve four fundamental areas: atmospheric and ocean sciences; solid-Earth sciences; hydrologic sciences; and space sciences. The organization's headquarters is located on Florida Avenue in Washington, D.C.
Paul Jozef Crutzen was a Dutch meteorologist and atmospheric chemist. He and Mario Molina and Frank Sherwood Rowland were awarded the Nobel Prize in Chemistry in 1995 for their work on atmospheric chemistry and specifically for his efforts in studying the formation and decomposition of atmospheric ozone. In addition to studying the ozone layer and climate change, he popularized the term Anthropocene to describe a proposed new epoch in the Quaternary period when human actions have a drastic effect on the Earth. He was also amongst the first few scientists to introduce the idea of a nuclear winter to describe the potential climatic effects stemming from large-scale atmospheric pollution including smoke from forest fires, industrial exhausts, and other sources like oil fires.
Roger A. Pielke Sr. is an American meteorologist with interests in climate variability and climate change, environmental vulnerability, numerical modeling, atmospheric dynamics, land/ocean – atmosphere interactions, and large eddy/turbulent boundary layer modeling. He particularly focuses on mesoscale weather and climate processes but also investigates on the global, regional, and microscale. Pielke is an ISI Highly Cited Researcher.
Charles David Keeling was an American scientist whose recording of carbon dioxide at the Mauna Loa Observatory confirmed Svante Arrhenius's proposition (1896) of the possibility of anthropogenic contribution to the greenhouse effect and global warming, by documenting the steadily rising carbon dioxide levels. The Keeling Curve measures the progressive buildup of carbon dioxide, a greenhouse gas, in the atmosphere.
Christopher William "Chris" Landsea is an American meteorologist, formerly a research meteorologist with the Hurricane Research Division of the Atlantic Oceanographic and Meteorological Laboratory at NOAA, and now the Science and Operations Officer at the National Hurricane Center. He is a member of the American Geophysical Union and the American Meteorological Society.
William F. Ruddiman is a palaeoclimatologist and Professor Emeritus at the University of Virginia. Ruddiman earned an undergraduate degree in geology in 1964 at Williams College, and a Ph.D. in marine geology from Columbia University in 1969. Ruddiman worked at the US Naval Oceanographic Office from 1969 to 1976, and at Columbia's Lamont–Doherty Earth Observatory from 1976 to 1991. He moved to Virginia in 1991, serving as a professor in Environmental Sciences. Ruddiman's research interests center on climate change over several time scales. He is a Fellow of both the Geological Society of America and the American Geophysical Union. Ruddiman has participated in 15 oceanographic cruises, and was co-chief of two deep-sea drilling cruises.
The Great Global Warming Swindle is a 2007 British polemical documentary film directed by Martin Durkin. The film denies the scientific consensus about the reality and causes of climate change, justifying this by suggesting that climatology is influenced by funding and political factors. The program was formally criticised by Ofcom, the UK broadcasting regulatory agency, which ruled the film failed to uphold due impartiality and upheld complaints of misrepresentation made by David King, who appeared in the film.
David John Karoly is an Australian atmospheric scientist, currently based at CSIRO.
Matthew England is a physical oceanographer and climate scientist. He is currently Scientia Professor of Ocean & Climate Dynamics at the University of New South Wales, Sydney, Australia.
Polar meteorology is the study of the atmosphere of Earth's polar regions. Surface temperature inversion is typical of polar environments and leads to the katabatic wind phenomenon. The vertical temperature structure of polar environments tends to be more complex than in mid-latitude or tropical climates.
Climate change has been a critical issue in Australia since the beginning of the 21st century. Australia is becoming hotter and more prone to extreme heat, bushfires, droughts, floods, and longer fire seasons because of climate change. Climate issues include wildfires, heatwaves, cyclones, rising sea levels, and erosion.
Greenhouse gases are the gases in the atmosphere that raise the surface temperature of planets such as the Earth. What distinguishes them from other gases is that they absorb the wavelengths of radiation that a planet emits, resulting in the greenhouse effect. The Earth is warmed by sunlight, causing its surface to radiate heat, which is then mostly absorbed by greenhouse gases. The most abundant greenhouse gases in Earth's atmosphere, listed in decreasing order of average global mole fraction, are: Water vapor, Carbon dioxide, Methane, Nitrous oxide, Ozone, Chlorofluorocarbons, Hydrofluorocarbons (HFCs), Perfluorocarbons, SF
6, and NF
3. Without greenhouse gases in the atmosphere, the average temperature of Earth's surface would be about −18 °C (0 °F), rather than the present average of 15 °C (59 °F). Water vapor is a potent greenhouse gas but not one that humans are directly adding to. It is therefore not one of the drivers of climate change that the IPCC is concerned with, and therefore not included in the IPCC list of greenhouse gases.
David Stuart Wratt is a New Zealand climate scientist who specialises in meteorology and the science and impact of climate change. He is an adjunct research fellow at the New Zealand Climate Change Research Institute at Victoria University of Wellington, and has had many roles at the National Institute of Water and Atmospheric Research (NIWA), including six years as chief scientist (climate). His current position at NIWA is emeritus scientist (climate). Wratt is a Companion of the Royal Society of New Zealand and was the chair of the society's New Zealand Climate Committee. He has had advisory roles for the New Zealand Government, including science advisor at the Ministry for the Environment, and is currently a member of the Science Board for the Ministry of Business, Innovation and Employment. He has had input into assessments by the Intergovernmental Panel on Climate Change (IPCC), notably, contributing to its award of the 2007 Nobel Peace Prize through his contributions to the IPCC Fourth Assessment Report. Wratt has worked in the United States and Australia as well as New Zealand.
Julie Michelle Arblaster is an Australian scientist. She is a Professor in the School of Earth, Atmosphere and Environment at Monash University. She was a contributing author on reports for which the Intergovernmental Panel on Climate Change (IPCC) was a co-recipient of the 2007 Nobel Peace Prize. Arblaster was a lead author on Chapter 12 of the IPCC Working Group I contribution to the IPCC Fifth Assessment Report in 2013. She has received the 2014 Anton Hales Medal for research in earth sciences from the Australian Academy of Science, and the 2017 Priestley Medal from the Australian Meteorological and Oceanographic Society. She has been ranked as one of the Top Influential Earth Scientists of 2010-2020, based on citations and discussion of her work.
Susan Elizabeth Anne Wijffels is an Australian oceanographer employed by the Woods Hole Oceanographic Institution (WHOI); she formerly worked from the Commonwealth Scientific and Industrial Research Organisation (CSIRO) in Australia. Wijffels specialises in quantifying global ocean change over the past 50 years, including its anatomy and drivers. She is recognised for her international and national leadership of the Global Ocean Observing System. She is regarded as an expert in the Indonesian Throughflow and its role in global climate.
CSIRO Oceans and Atmosphere (O&A) (2014–2022) was one of the then 8 Business Units of the Commonwealth Scientific and Industrial Research Organisation (CSIRO), Australia's largest government-supported science research agency. In December 2022 it was merged with CSIRO Land and Water to form a single, larger Business Unit called simply, "CSIRO Environment".
