Editing Wildfire (section)

=== Carbon dioxide and other emissions from fires ===
The carbon released from wildfires can add to greenhouse gas concentrations. [[Climate model]]s do not yet fully reflect this [[Climate change feedbacks|feedback]].<ref name="IPCC-2021">IPCC, 2021: [https://www.ipcc.ch/report/ar6/wg1/downloads/report/IPCC_AR6_WGI_SPM.pdf Summary for Policymakers] {{Webarchive|url=https://web.archive.org/web/20210811205522/https://www.ipcc.ch/report/ar6/wg1/downloads/report/IPCC_AR6_WGI_SPM.pdf |date=11 August 2021 }}. In: [https://www.ipcc.ch/report/ar6/wg1/ Climate Change 2021: The Physical Science Basis. Contribution of Working Group I to the Sixth Assessment Report of the Intergovernmental Panel on Climate Change] {{Webarchive|url=https://web.archive.org/web/20230526182346/https://www.ipcc.ch/report/ar6/wg1/downloads/report/IPCC_AR6_WGI_Chapter09.pdf |date=26 May 2023 }} {{cite book |doi=10.1017/9781009157896.001 |chapter=Summary for Policymakers |title=Climate Change 2021 – the Physical Science Basis |date=2023 |pages=3–32 |isbn=978-1-009-15789-6 }}</ref>{{rp|20}}

Wildfires release large amounts of carbon dioxide, black and brown carbon particles, and ozone precursors such as [[volatile organic compound]]s and [[NOx|nitrogen oxides (NOx)]] into the atmosphere.<ref>{{Cite journal|last1=Spracklen|first1=Dominick V.|last2=Logan|first2=Jennifer A.|author-link2=Jennifer Logan|last3=Mickley|first3=Loretta J.|last4=Park|first4=Rokjin J.|last5=Yevich|first5=Rosemarie|last6=Westerling|first6=Anthony L.|last7=Jaffe|first7=Dan A.|date=2007|title=Wildfires drive interannual variability of organic carbon aerosol in the western U.S. in summer|journal=Geophysical Research Letters|language=en|volume=34|issue=16|doi=10.1029/2007GL030037|bibcode=2007GeoRL..3416816S|s2cid=5642896|issn=1944-8007|doi-access=free}}</ref><ref>{{cite journal |last1=Wofsy |first1=S. C. |last2=Sachse |first2=G. W. |last3=Gregory |first3=G. L. |last4=Blake |first4=D. R. |last5=Bradshaw |first5=J. D. |last6=Sandholm |first6=S. T. |last7=Singh |first7=H. B. |last8=Barrick |first8=J. A. |last9=Harriss |first9=R. C. |last10=Talbot |first10=R. W. |last11=Shipham |first11=M. A. |last12=Browell |first12=E. V. |last13=Jacob |first13=D. J. |last14=Logan |first14=J. A. |title=Atmospheric chemistry in the Arctic and subarctic: Influence of natural fires, industrial emissions, and stratospheric inputs |journal=Journal of Geophysical Research: Atmospheres |date=30 October 1992 |volume=97 |issue=D15 |pages=16731–16746 |doi=10.1029/92JD00622 |bibcode=1992JGR....9716731W |url=https://escholarship.org/uc/item/500382zz }}</ref> These emissions affect radiation, clouds, and climate on regional and even global scales.<ref name=dangelo2022 /> Wildfires also emit substantial amounts of semi-volatile organic species that can partition from the gas phase to form [[secondary organic aerosol]] (SOA) over hours to days after emission. In addition, the formation of the other pollutants as the air is transported can lead to harmful exposures for populations in regions far away from the wildfires.<ref>{{Cite web|url=https://www.esrl.noaa.gov/csd/factsheets/csdWildfiresFIREX.pdf|title=The Impact of Wildfires on Climate and Air Quality|website=National Oceanic and Atmospheric Administration|access-date=21 February 2020|archive-date=2 June 2019|archive-url=https://web.archive.org/web/20190602215528/https://www.esrl.noaa.gov/csd/factsheets/csdWildfiresFIREX.pdf|url-status=live}}</ref><ref name=dangelo2022 /> While direct emissions of harmful pollutants can affect first responders and residents, wildfire smoke can also be transported over long distances and impact air quality across local, regional, and global scales.<ref>{{Cite web|last=US EPA|first=ORD|date=30 March 2017|title=Wildland Fire Research: Health Effects Research|url=https://www.epa.gov/air-research/wildland-fire-research-health-effects-research|access-date=28 November 2020|website=US EPA|language=en|archive-date=2 May 2023|archive-url=https://web.archive.org/web/20230502201707/https://www.epa.gov/air-research/wildland-fire-research-health-effects-research|url-status=live}}</ref>[[File:The_Rim_Fire_in_the_Stanislaus_National_Forest_near_in_California_began_on_Aug._17,_2013-0004.jpg|thumb|Wildfire near [[Yosemite National Park]], United States, in 2013. The [[Rim Fire]] burned more than {{convert|250,000|acres|km2}} of forest.]]The health effects of wildfire smoke, such as worsening [[Circulatory system|cardiovascular]] and respiratory conditions, extend beyond immediate exposure, contributing to nearly 16,000 annual deaths, a number expected to rise to 30,000 by 2050. The economic impact is also significant, with projected costs reaching $240 billion annually by 2050, surpassing other climate-related damages.<ref>{{Cite web |last=Borunda |first=Alejandra |date=18 April 2024 |title=Wildfire smoke contributes to thousands of deaths each year in the U.S. |url=https://www.npr.org/2024/04/18/1245068810/wildfire-smoke-contributes-to-thousands-of-deaths-each-year-in-the-u-s |access-date=27 April 2024 |website=www.npr.org |archive-date=23 April 2024 |archive-url=https://web.archive.org/web/20240423235910/https://www.npr.org/2024/04/18/1245068810/wildfire-smoke-contributes-to-thousands-of-deaths-each-year-in-the-u-s |url-status=live }}</ref>

Over the past century, wildfires have accounted for 20–25% of global carbon emissions, the remainder from human activities.<ref>{{cite news |url=https://www.bloomberg.com/graphics/2020-fire-emissions/ |publisher=[[Bloomberg L.P.|Bloomberg]] |title=Measuring the Carbon-Dioxide Cost of Last Year's Worldwide Wildfires |author1=Laura Millan Lombrana |author2=Hayley Warren |author3=Akshat Rathi |date=10 February 2020 |access-date=1 January 2021 |archive-date=28 January 2023 |archive-url=https://web.archive.org/web/20230128174413/https://www.bloomberg.com/graphics/2020-fire-emissions/ |url-status=live }}</ref> Global carbon emissions from wildfires through August 2020 equaled the average annual emissions of the [[European Union]].<ref name="global-carbon-fire-2019">{{cite news |last1=Boyle |first1=Louise |date=27 August 2020 |title=Global fires are up 13% from 2019's record-breaking numbers |agency=The Independent |url=https://www.independent.co.uk/environment/climate-crisis-fires-global-heating-amazon-california-eu-a9690146.html |access-date=8 September 2020 |archive-date=14 January 2021 |archive-url=https://web.archive.org/web/20210114222322/https://www.independent.co.uk/environment/climate-crisis-fires-global-heating-amazon-california-eu-a9690146.html |url-status=live }}</ref> In 2020, the carbon released by California's wildfires was significantly larger than the state's other carbon emissions.<ref>{{cite news |url=https://news.mongabay.com/2020/09/off-the-chart-co2-from-california-fires-dwarf-states-fossil-fuel-emissions/ |publisher=Mongabay |title='Off the chart': CO2 from California fires dwarf state's fossil fuel emissions |first=Elizabeth Claire |last=Alberts |date=18 September 2020 |access-date=1 January 2021 |archive-date=30 June 2023 |archive-url=https://web.archive.org/web/20230630232806/https://news.mongabay.com/2020/09/off-the-chart-co2-from-california-fires-dwarf-states-fossil-fuel-emissions/ |url-status=live }}</ref>

Forest fires in Indonesia in 1997 were estimated to have released between 0.81 and 2.57&nbsp;gigatonnes (0.89 and 2.83&nbsp;billion [[short ton]]s) of CO<sub>2</sub> into the atmosphere, which is between 13–40% of the annual global carbon dioxide emissions from burning fossil fuels.<ref>{{cite journal |last=Page |first=Susan E. |author2=Florian Siegert |author3=John O. Rieley |author4=Hans-Dieter V. Boehm |author5=Adi Jaya |author6=Suwido Limin |name-list-style=amp |date=11 July 2002 |title=The amount of carbon released from peat and forest fires in Indonesia during 1997 |journal=Nature |volume=420 |issue=6911 |pages=61–65 |bibcode=2002Natur.420...61P |doi=10.1038/nature01131 |pmid=12422213 }}</ref><ref>{{cite journal |last=Tacconi |first=Luca |date=February 2003 |title=Fires in Indonesia: Causes, Costs, and Policy Implications (CIFOR Occasional Paper No. 38) |url=http://www.cifor.cgiar.org/publications/pdf_files/OccPapers/OP-038.pdf |journal=Occasional Paper |publisher=Center for International Forestry Research |issn=0854-9818 |archive-url=https://web.archive.org/web/20090226080558/http://www.cifor.cgiar.org/publications/pdf_files/OccPapers/OP-038.pdf |archive-date=26 February 2009 |access-date=6 February 2009 |place=Bogor, Indonesia }}</ref>

In June and July 2019, fires in the Arctic emitted more than 140 megatons of carbon dioxide, according to an analysis by CAMS. To put that into perspective this amounts to the same amount of carbon emitted by 36 million cars in a year. The recent wildfires and their massive CO<sub>2</sub> emissions mean that it will be important to take them into consideration when implementing measures for reaching greenhouse gas reduction targets accorded with the [[Paris climate agreement]].<ref>{{Cite web |last=Bassetti |first=Francesco |date=31 August 2019 |title=The Effects of Wildfires on a Zero Carbon Future |url=https://www.climateforesight.eu/future-earth/the-effects-of-wildfires-on-a-zero-carbon-future/ |archive-url=https://web.archive.org/web/20201128165555/https://www.climateforesight.eu/future-earth/the-effects-of-wildfires-on-a-zero-carbon-future/ |archive-date=28 November 2020 |access-date=16 November 2020}}</ref> Due to the complex oxidative chemistry occurring during the transport of wildfire smoke in the atmosphere,<ref>{{Cite journal |last1=Rana |first1=Md. Sohel |last2=Guzman |first2=Marcelo I. |date=22 October 2020 |title=Oxidation of Phenolic Aldehydes by Ozone and Hydroxyl Radicals at the Air–Water Interface |journal=The Journal of Physical Chemistry A |volume=124 |issue=42 |pages=8822–8833 |bibcode=2020JPCA..124.8822R |doi=10.1021/acs.jpca.0c05944 |issn=1089-5639 |pmid=32931271 |doi-access=free}}</ref> the toxicity of emissions was indicated to increase over time.<ref>{{Cite web |date=15 October 2020 |title=Wildfire Smoke Toxicity Increases Over Time, Poses Public Health Risk, According to UK Chemist |url=https://uknow.uky.edu/research/wildfire-smoke-toxicity-increases-over-time-poses-public-health-risk-according-uk-chemist |access-date=31 October 2020 |website=UKNow |archive-date=4 April 2023 |archive-url=https://web.archive.org/web/20230404065812/https://uknow.uky.edu/research/wildfire-smoke-toxicity-increases-over-time-poses-public-health-risk-according-uk-chemist |url-status=live }}</ref><ref>{{Cite web |title=As smoke from forest fires ages in the atmosphere its toxicity increases |url=https://phys.org/news/2020-10-forest-ages-atmosphere-toxicity.html |access-date=31 October 2020 |website=phys.org |language=en |archive-date=4 April 2023 |archive-url=https://web.archive.org/web/20230404014637/https://phys.org/news/2020-10-forest-ages-atmosphere-toxicity.html |url-status=live }}</ref>

Atmospheric models suggest that these concentrations of sooty particles could increase absorption of incoming [[solar radiation]] during winter months by as much as 15%.<ref>{{cite conference |author=Baumgardner, D. |display-authors=etal |date=2003 |title=Warming of the Arctic lower stratosphere by light absorbing particles |book-title=American Geophysical Union fall meeting |place=San Francisco, California}}</ref> The Amazon is estimated to hold around 90 billion tons of carbon. As of 2019, the earth's atmosphere has 415 parts per million of carbon, and the destruction of the Amazon would add about 38 parts per million.<ref>{{Cite news |last=Mufson |first=Steven |title=What you need to know about the Amazon rainforest fires |newspaper=Washington post |url=https://www.washingtonpost.com/climate-environment/what-you-need-to-know-about-the-amazon-rainforest-fires/2019/08/27/ac82b21e-c815-11e9-a4f3-c081a126de70_story.html |archive-url=https://web.archive.org/web/20190827182809/https://www.washingtonpost.com/climate-environment/what-you-need-to-know-about-the-amazon-rainforest-fires/2019/08/27/ac82b21e-c815-11e9-a4f3-c081a126de70_story.html |archive-date=27 August 2019}}</ref>

Some research has shown wildfire smoke can have a cooling effect.<ref>{{Cite journal |title=Wildfire smoke cools summer river and stream water temperatures |url=https://www.fs.usda.gov/research/treesearch/57160 |journal=Water Resources Research |date=2018 |doi=10.1029/2018WR022964 |last1=David |first1=Aaron T. |last2=Asarian |first2=J. Eli |last3=Lake |first3=Frank K. |volume=54 |issue=10 |pages=7273–7290 |bibcode=2018WRR....54.7273D |doi-access=free |access-date=26 July 2023 |archive-date=26 July 2023 |archive-url=https://web.archive.org/web/20230726231753/https://www.fs.usda.gov/research/treesearch/57160 |url-status=live }}</ref><ref>{{Cite web |title=How Extreme Weather can Cool the Planet |url=https://www.nationalgeographic.com/environment/article/how-extreme-fire-weather-can-cool-the-planet |archive-url=https://web.archive.org/web/20210806143520/https://www.nationalgeographic.com/environment/article/how-extreme-fire-weather-can-cool-the-planet |archive-date=6 August 2021 |website=National Geographic|date=6 August 2021 }}</ref><ref>{{Cite journal |title=Significant Effective Radiative Forcing of Stratospheric Wildfire Smoke |journal=Geophysical Research Letters|year=2022 |doi=10.1029/2022GL100175 |last1=Liu |first1=Cheng-Cheng |last2=Portmann |first2=Robert W. |last3=Liu |first3=Shang |last4=Rosenlof |first4=Karen H. |last5=Peng |first5=Yifeng |last6=Yu |first6=Pengfei |volume=49 |issue=17 |bibcode=2022GeoRL..4900175L |s2cid=252148515 |doi-access=free }}</ref>

Research in 2007 stated that black carbon in snow changed temperature three times more than atmospheric carbon dioxide. As much as 94 percent of Arctic warming may be caused by dark carbon on snow that initiates melting. The dark carbon comes from fossil fuels burning, wood and other biofuels, and forest fires. Melting can occur even at low concentrations of dark carbon (below five parts per billion).<ref name="Biello 2007 m566">{{cite web | last=Biello | first=David | title=Impure as the Driven Snow | website=Scientific American | date=8 June 2007 | url=https://www.scientificamerican.com/article/impure-as-the-driven-snow/ | access-date=7 November 2023 | archive-date=7 November 2023 | archive-url=https://web.archive.org/web/20231107222307/https://www.scientificamerican.com/article/impure-as-the-driven-snow/ | url-status=live }}</ref>