Konsensus ilmiah tentang perubahan iklim adalah konsensus para ilmuwan iklim mengenai sejauh mana pemanasan global terjadi, kemungkinan penyebabnya, dan kemungkinan konsekuensinya. Saat ini, ada konsensus ilmiah yang kuat bahwa bumi sedang memanas dan bahwa pemanasan ini terutama disebabkan oleh aktivitas manusia. Konsensus ini didukung oleh berbagai studi tentang opini ilmuwan dan oleh pernyataan posisi organisasi ilmiah, yang banyak di antaranya secara eksplisit setuju dengan laporan sintesis Panel Antarpemerintah tentang Perubahan Iklim (IPCC).
Konsensus ilmiah tentang perubahan iklim adalah konsensus para ilmuwan iklim mengenai sejauh mana pemanasan global terjadi, kemungkinan penyebabnya, dan kemungkinan konsekuensinya. Saat ini, ada konsensus ilmiah yang kuat bahwa bumi sedang memanas dan bahwa pemanasan ini terutama disebabkan oleh aktivitas manusia. Konsensus ini didukung oleh berbagai studi tentang opini ilmuwan dan oleh pernyataan posisi organisasi ilmiah, yang banyak di antaranya secara eksplisit setuju dengan laporan sintesis Panel Antarpemerintah tentang Perubahan Iklim (IPCC).
Poin konsensus
Konsensus ilmiah saat ini adalah:
Iklim bumi telah menghangat secara signifikan sejak akhir 1800-an.
Beberapa studi tentang konsensus telah dilakukan.[1] Di antara yang paling banyak dikutip adalah studi 2013 terhadap hampir 12.000 abstrak dari makalah yang ditelaah sejawat tentang ilmu iklim yang diterbitkan sejak 1990, di mana lebih dari 4.000 makalah menyatakan pendapat tentang penyebab pemanasan global baru-baru ini. Dari jumlah tersebut, 97% setuju, secara eksplisit atau implisit, bahwa pemanasan global sedang terjadi dan disebabkan oleh manusia.[2][3] "Sangat mungkin"[4] bahwa pemanasan global disebabkan oleh "aktivitas manusia, terutama emisi gas rumah kaca"[4] di atmosfer.[5] Perubahan alami saja akan memiliki sedikit efek pendinginan, bukan efek pemanasan.[6][7][8][9]
Opini ilmiah ini diungkapkan dalam laporan sintesis, oleh badan-badan ilmiah berstandar nasional atau internasional, dan oleh survei pendapat di antara para ilmuwan iklim. Masing-masing ilmuwan, universitas, dan laboratorium berkontribusi terhadap opini ilmiah secara keseluruhan melalui publikasi yang ditinjau oleh rekan sejawatnya, dan bagian-bagian yang disepakati bersama dan relatif pasti dirangkum dalam laporan dan survei yang dihormati ini.[10] Laporan Penilaian Kelima (AR5) IPCC diselesaikan pada 2014.[11] Kesimpulannya dirangkum di bawah ini:
"Pemanasan sistem iklim sangat jelas, dan sejak 1950-an, banyak perubahan yang diamati belum pernah terjadi selama beberapa dekade hingga ribuan tahun."[12]
"Konsentrasi karbon dioksida, metana, dan dinitrogen oksida di atmosfer telah meningkat ke tingkat yang belum pernah terjadi sebelumnya dalam setidaknya 800.000 tahun terakhir."[13]
Pengaruh manusia terhadap sistem iklim jelas.[14] Sangat mungkin (probabilitas 95-100%)[15] bahwa pengaruh manusia adalah penyebab dominan pemanasan global antara 1951-2010.[14]
"Semakin besar pemanasan [global] meningkatkan kemungkinan dampak yang parah, pervasif, dan tidak dapat balik."[16]
"Langkah pertama menuju adaptasi terhadap perubahan iklim pada masa depan adalah mengurangi kerentanan dan paparan terhadap variabilitas iklim saat ini."[17]
"Risiko keseluruhan dari dampak perubahan iklim dapat dikurangi dengan membatasi laju dan besarnya perubahan iklim"[16]
Peningkatan emisi gas rumah kaca global saat ini tidak konsisten dengan membatasi pemanasan global di bawah 1,5 atau 2°C, relatif terhadap tingkat pra-industri.[19] Janji yang dibuat sebagai bagian dari Perjanjian Cancún secara luas konsisten dengan skenario hemat biaya yang memberikan peluang "mungkin" (peluang 66-100%) untuk membatasi pemanasan global (pada tahun 2100) hingga di bawah 3°C, relatif terhadap tingkat pra-industri.[20]
Pengaruh pemanasan gas rumah kaca di atmosfer telah meningkat secara substansial selama beberapa dekade terakhir. Pada 2017, annual greenhouse gas index (AGGI) adalah 1,42, yang merupakan peningkatan lebih dari 40% sejak 1990.
Beberapa badan ilmiah telah merekomendasikan kebijakan khusus kepada pemerintah, dan sains dapat berperan dalam menginformasikan respons yang efektif terhadap perubahan iklim. Namun, keputusan kebijakan mungkin membutuhkan penilaian nilai dan karenanya tidak dimasukkan dalam pendapat ilmiah.[21][22]
Tidak ada badan ilmiah yang memiliki kedudukan nasional atau internasional yang memiliki pendapat resmi yang berbeda dari poin-poin utama ini. Badan ilmiah nasional atau internasional terakhir yang menyatakan perbedaan pendapat adalah American Association of Petroleum Geologists,[23] yang pada 2007[24] memperbarui pernyataannya ke posisi non-komitmen yang masih dipegang saat ini.[25] Beberapa organisasi lain, terutama yang berfokus pada geologi, juga memegang posisi non-komitmen.
↑"Scientific consensus: Earth's climate is warming". Climate Change: Vital Signs of the Planet. National Aeronautics and Space Administration (NASA). Diarsipkan dari asli tanggal June 17, 2019. Diakses tanggal 2018-08-18. Multiple studies published in peer-reviewed scientific journals1 show that 97 percent or more of actively publishing climate scientists agree: Climate-warming trends over the past century are extremely likely due to human activities. In addition, most of the leading scientific organizations worldwide have issued public statements endorsing this position.
↑IPCC, "Summary for Policymakers"(PDF), Detection and Attribution of Climate Change, «It is extremely likely that human influence has been the dominant cause of the observed warming since the mid-20th century» (page 17) and «In this Summary for Policymakers, the following terms have been used to indicate the assessed likelihood of an outcome or a result: (...) extremely likely: 95–100%» (page 2)., in IPCC AR5 WG1 2013.
↑[Notes-SciPanel] America's Climate Choices: Panel on Advancing the Science of Climate Change; National Research Council (2010). Advancing the Science of Climate Change. Washington, D.C.: The National Academies Press. ISBN0-309-14588-0. Diarsipkan dari asli tanggal 2014-05-29. (p1) ... there is a strong, credible body of evidence, based on multiple lines of research, documenting that climate is changing and that these changes are in large part caused by human activities. While much remains to be learned, the core phenomenon, scientific questions, and hypotheses have been examined thoroughly and have stood firm in the face of serious scientific debate and careful evaluation of alternative explanations. * * * (p21-22) Some scientific conclusions or theories have been so thoroughly examined and tested, and supported by so many independent observations and results, that their likelihood of subsequently being found to be wrong is vanishingly small. Such conclusions and theories are then regarded as settled facts. This is the case for the conclusions that the Earth system is warming and that much of this warming is very likely due to human activities.Pemeliharaan CS1: Banyak nama: authors list (link)
↑IPCC, 2014: Climate Change 2014: Synthesis Report. Contribution of Working Groups I, II and III to the Fifth Assessment Report of the Intergovernmental Panel on Climate Change [Core Writing Team, R. K. Pachauri and L. A. Meyer (eds.)]. IPCC, Geneva, Switzerland, 151 pp.
AAP Global Climate Change and Children's Health, 2007, diarsipkan dari asli tanggal 2009-07-22, diakses tanggal 2009-02-13 "There is broad scientific consensus that Earth's climate is warming rapidly and at an accelerating rate. Human activities, primarily the burning of fossil fuels, are very likely (>90% probability) to be the main cause of this warming. Climate-sensitive changes in ecosystems are already being observed, and fundamental, potentially irreversible, ecological changes may occur in the coming decades. Conservative environmental estimates of the impact of climate changes that are already in process indicate that they will result in numerous health effects to children. Anticipated direct health consequences of climate change include injury and death from extreme weather events and natural disasters, increases in climate-sensitive infectious diseases, increases in air pollution–related illness, and more heat-related, potentially fatal, illness. Within all of these categories, children have increased vulnerability compared with other groups."
AAWV Position Statement on Climate Change, Wildlife Diseases, and Wildlife Health "There is widespread scientific agreement that the world's climate is changing and that the weight of evidence demonstrates that anthropogenic factors have and will continue to contribute significantly to global warming and climate change. It is anticipated that continuing changes to the climate will have serious negative impacts on public, animal and ecosystem health due to extreme weather events, changing disease transmission dynamics, emerging and re-emerging diseases, and alterations to habitat and ecological systems that are essential to wildlife conservation. Furthermore, there is increasing recognition of the inter-relationships of human, domestic animal, wildlife, and ecosystem health as illustrated by the fact the majority of recent emerging diseases have a wildlife origin."
ACPM Policy Statement Abrupt Climate Change and Public Health Implications, 2006, diarsipkan dari asli tanggal 2007-11-07, diakses tanggal 2008-11-21 "The American College of Preventive Medicine (ACPM) accept the position that global warming and climate change is occurring, that there is potential for abrupt climate change, and that human practices that increase greenhouse gases exacerbate the problem, and that the public health consequences may be severe."
AIP science policy document.(PDF), 2005 "Policy: The AIP supports a reduction of the green house gas emissions that are leading to increased global temperatures, and encourages research that works towards this goal. Reason: Research in Australia and overseas shows that an increase in global temperature will adversely affect the Earth's climate patterns. The melting of the polar ice caps, combined with thermal expansion, will lead to rises in sea levels that may impact adversely on our coastal cities. The impact of these changes on biodiversity will fundamentally change the ecology of Earth."
AIBS Position Statements "Observations throughout the world make it clear that climate change is occurring, and rigorous scientific research demonstrates that the greenhouse gases emitted by human activities are the primary driver."
AMA Climate Change and Human Health — 2004, 2004[pranala nonaktif permanen] They recommend policies "to mitigate the possible consequential health effects of climate change through improved energy efficiency, clean energy production and other emission reduction steps."
"ACIA Display". Amap.no. Diarsipkan dari asli tanggal 2010-12-14. Diakses tanggal 2012-07-30.
AMA Climate Change and Human Health — 2004. Revised 2008., 2008, diarsipkan dari asli tanggal 2009-02-16 "The world's climate – our life-support system – is being altered in ways that are likely to pose significant direct and indirect challenges to health. While ‘climate change’ can be due to natural forces or human activity, there is now substantial evidence to indicate that human activity – and specifically increased greenhouse gas (GHGs) emissions – is a key factor in the pace and extent of global temperature increases. Health impacts of climate change include the direct impacts of extreme events such as storms, floods, heatwaves and fires and the indirect effects of longer-term changes, such as drought, changes to the food and water supply, resource conflicts and population shifts. Increases in average temperatures mean that alterations in the geographic range and seasonality of certain infections and diseases (including vector-borne diseases such as malaria, dengue fever, Ross River virus and food-borne infections such as Salmonellosis) may be among the first detectable impacts of climate change on human health. Human health is ultimately dependent on the health of the planet and its ecosystem. The AMA believes that measures which mitigate climate change will also benefit public health. Reducing GHGs should therefore be seen as a public health priority."
American Chemical Society Global Climate Change "Careful and comprehensive scientific assessments have clearly demonstrated that the Earth's climate system is changing rapidly in response to growing atmospheric burdens of greenhouse gases and absorbing aerosol particles (IPCC, 2007). There is very little room for doubt that observed climate trends are due to human activities. The threats are serious and action is urgently needed to mitigate the risks of climate change. The reality of global warming, its current serious and potentially disastrous impacts on Earth system properties, and the key role emissions from human activities play in driving these phenomena have been recognized by earlier versions of this ACS policy statement (ACS, 2004), by other major scientific societies, including the American Geophysical Union (AGU, 2003), the American Meteorological Society (AMS, 2007) and the American Association for the Advancement of Science (AAAS, 2007), and by the U. S. National Academies and ten other leading national academies of science (NA, 2005)."
American Physical Society Climate Change Policy Statement, November 2007 "Emissions of greenhouse gases from human activities are changing the atmosphere in ways that affect the Earth's climate. Greenhouse gases include carbon dioxide as well as methane, nitrous oxide and other gases. They are emitted from fossil fuel combustion and a range of industrial and agricultural processes. The evidence is incontrovertible: Global warming is occurring. If no mitigating actions are taken, significant disruptions in the Earth's physical and ecological systems, social systems, security and human health are likely to occur. We must reduce emissions of greenhouse gases beginning now. Because the complexity of the climate makes accurate prediction difficult, the APS urges an enhanced effort to understand the effects of human activity on the Earth's climate, and to provide the technological options for meeting the climate challenge in the near and longer terms. The APS also urges governments, universities, national laboratories and its membership to support policies and actions that will reduce the emission of greenhouse gases.
American Medical Association Policy Statement, 2008 "Support the findings of the latest Intergovernmental Panel on Climate Change report, which states that the Earth is undergoing adverse global climate change and that these changes will negatively affect public health. Support educating the medical community on the potential adverse public health effects of global climate change, including topics such as population displacement, flooding, infectious and vector-borne diseases, and healthy water supplies."
ASA Statement on Climate Change, November 30, 2007 "The ASA endorses the IPCC conclusions.... Over the course of four assessment reports, a small number of statisticians have served as authors or reviewers. Although this involvement is encouraging, it does not represent the full range of statistical expertise available. ASA recommends that more statisticians should become part of the IPCC process. Such participation would be mutually beneficial to the assessment of climate change and its impacts and also to the statistical community."
Australian Coral Reef Society official letter(PDF), 2006, diarsipkan dari asli(PDF) tanggal 22 March 2006 Official communique regarding the Great Barrier Reef and the "world-wide decline in coral reefs through processes such as overfishing, runoff of nutrients from the land, coral bleaching, global climate change, ocean acidification, pollution", etc.: There is almost total consensus among experts that the earth's climate is changing as a result of the build-up of greenhouse gases. The IPCC (involving over 3,000 of the world's experts) has come out with clear conclusions as to the reality of this phenomenon. One does not have to look further than the collective academy of scientists worldwide to see the string (of) statements on this worrying change to the earth's atmosphere. There is broad scientific consensus that coral reefs are heavily affected by the activities of man and there are significant global influences that can make reefs more vulnerable such as global warming....It is highly likely that coral bleaching has been exacerbated by global warming."
EPS Position Paper Energy for the future: The Nuclear Option(PDF), 2007 "The emission of anthropogenic greenhouse gases, among which carbon dioxide is the main contributor, has amplified the natural greenhouse effect and led to global warming. The main contribution stems from burning fossil fuels. A further increase will have decisive effects on life on earth. An energy cycle with the lowest possible CO2 emission is called for wherever possible to combat climate change."
"EFG Website | Home". Eurogeologists.de. 2011-08-10. Diakses tanggal 2012-07-30.
European Science Foundation Position Paper Impacts of Climate Change on the European Marine and Coastal Environment — Ecosystems Approach, 2007, hlm.7–10 "There is now convincing evidence that since the industrial revolution, human activities, resulting in increasing concentrations of greenhouse gases have become a major agent of climate change. These greenhouse gases affect the global climate by retaining heat in the troposphere, thus raising the average temperature of the planet and altering global atmospheric circulation and precipitation patterns. While on-going national and international actions to curtail and reduce greenhouse gas emissions are essential, the levels of greenhouse gases currently in the atmosphere, and their impact, are likely to persist for several decades. On-going and increased efforts to mitigate climate change through reduction in greenhouse gases are therefore crucial."
FASTS Statement on Climate Change(PDF), 2008 "Global climate change is real and measurable. Since the start of the 20th century, the global mean surface temperature of the Earth has increased by more than 0.7°C and the rate of warming has been largest in the last 30 years. Key vulnerabilities arising from climate change include water resources, food supply, health, coastal settlements, biodiversity and some key ecosystems such as coral reefs and alpine regions. As the atmospheric concentration of greenhouse gases increases, impacts become more severe and widespread. To reduce the global net economic, environmental and social losses in the face of these impacts, the policy objective must remain squarely focused on returning greenhouse gas concentrations to near pre-industrial levels through the reduction of emissions. The spatial and temporal fingerprint of warming can be traced to increasing greenhouse gas concentrations in the atmosphere, which are a direct result of burning fossil fuels, broad-scale deforestation and other human activity."
Global Environmental Change — Microbial Contributions, Microbial Solutions(PDF), American Society For Microbiology, May 2006 They recommended "reducing net anthropogenic CO2 emissions to the atmosphere" and "minimizing anthropogenic disturbances of" atmospheric gases. Carbon dioxide concentrations were relatively stable for the past 10,000 years but then began to increase rapidly about 150 years ago…as a result of fossil fuel consumption and land use change. Of course, changes in atmospheric composition are but one component of global change, which also includes disturbances in the physical and chemical conditions of the oceans and land surface. Although global change has been a natural process throughout Earth's history, humans are responsible for substantially accelerating present-day changes. These changes may adversely affect human health and the biosphere on which we depend. Outbreaks of a number of diseases, including Lyme disease, hantavirus infections, dengue fever, bubonic plague, and cholera, have been linked to climate change."
IAGLR Fact Sheet The Great Lakes at a Crossroads: Preparing for a Changing Climate(PDF), February 2009 "While the Earth's climate has changed many times during the planet's history because of natural factors, including volcanic eruptions and changes in the Earth's orbit, never before have we observed the present rapid rise in temperature and carbon dioxide (CO2). Human activities resulting from the industrial revolution have changed the chemical composition of the atmosphere....Deforestation is now the second largest contributor to global warming, after the burning of fossil fuels. These human activities have significantly increased the concentration of "greenhouse gases" in the atmosphere. As the Earth's climate warms, we are seeing many changes: stronger, more destructive hurricanes; heavier rainfall; more disastrous flooding; more areas of the world experiencing severe drought; and more heat waves."
Institute of Biology policy page ‘Climate Change’ "there is scientific agreement that the rapid global warming that has occurred in recent years is mostly anthropogenic, ie due to human activity." As a consequence of global warming, they warn that a "rise in sea levels due to melting of ice caps is expected to occur. Rises in temperature will have complex and frequently localised effects on weather, but an overall increase in extreme weather conditions and changes in precipitation patterns are probable, resulting in flooding and drought. The spread of tropical diseases is also expected." Subsequently, the Institute of Biology advocates policies to reduce "greenhouse gas emissions, as we feel that the consequences of climate change are likely to be severe."
IPENZ Informatory Note, Climate Change and the greenhouse effect(PDF), October 2001 "Human activities have increased the concentration of these atmospheric greenhouse gases, and although the changes are relatively small, the equilibrium maintained by the atmosphere is delicate, and so the effect of these changes is significant. The world's most important greenhouse gas is carbon dioxide, a by-product of the burning of fossil fuels. Since the time of the Industrial Revolution about 200 years ago, the concentration of carbon dioxide in the atmosphere has increased from about 280 parts per million to 370 parts per million, an increase of around 30%. On the basis of available data, climate scientists are now projecting an average global temperature rise over this century of 2.0 to 4.5°C. This compared with 0.6°C over the previous century – about a 500% increase... This could lead to changing, and for all emissions scenarios more unpredictable, weather patterns around the world, less frost days, more extreme events (droughts and storm or flood disasters), and warmer sea temperatures and melting glaciers causing sea levels to rise. ... Professional engineers commonly deal with risk, and frequently have to make judgments based on incomplete data. The available evidence suggests very strongly that human activities have already begun to make significant changes to the earth's climate, and that the long-term risk of delaying action is greater than the cost of avoiding/minimising the risk."
Stevens, William K. (2007-02-06). "On the Climate Change Beat, Doubt Gives Way to Certainty". New York Times. Diakses tanggal 2010-08-28. The Intergovernmental Panel on Climate Change said the likelihood was 90 percent to 99 percent that emissions of heat-trapping greenhouse gases like carbon dioxide, spewed from tailpipes and smokestacks, were the dominant cause of the observed warming of the last 50 years. In the panel's parlance, this level of certainty is labeled "very likely." Only rarely does scientific odds-making provide a more definite answer than that, at least in this branch of science, and it describes the endpoint, so far, of a progression.
Policy Statement, Climate Change and Energy, February 2007 "Engineers Australia believes that Australia must act swiftly and proactively in line with global expectations to address climate change as an economic, social and environmental risk... We believe that addressing the costs of atmospheric emissions will lead to increasing our competitive advantage by minimising risks and creating new economic opportunities. Engineers Australia believes the Australian Government should ratify the Kyoto Protocol."
Rosenthal, Elisabeth; Revkin, Andrew C. (2007-02-03). "Science Panel Calls Global Warming 'Unequivocal'". New York Times. Diakses tanggal 2010-08-28. the leading international network of climate scientists has concluded for the first time that global warming is 'unequivocal' and that human activity is the main driver, 'very likely' causing most of the rise in temperatures since 1950
SAF Forest Management and Climate Change (PDF), 2008, diarsipkan dari asli(PDF) tanggal 2012-02-22, diakses tanggal 2009-01-29 "Forests are shaped by climate....Changes in temperature and precipitation regimes therefore have the potential to dramatically affect forests nationwide. There is growing evidence that our climate is changing. The changes in temperature have been associated with increasing concentrations of atmospheric carbon dioxide (CO2) and other GHGs in the atmosphere."
SAF Forest Offset Projects in a Carbon Trading System(PDF), 2008, diarsipkan dari asli(PDF) tanggal 2012-02-22, diakses tanggal 2009-01-29 "Forests play a significant role in offsetting CO2 emissions, the primary anthropogenic GHG."
"Stanowisko Zgromadzenia Ogólnego PAN z dnia 13 grudnia 2007 r"(PDF) (dalam bahasa Polish). Polish Academy of Sciences. Diakses tanggal 2009-06-16. Pemeliharaan CS1: Bahasa yang tidak diketahui (link)Note: As of 16 June 2009, PAS has not issued this statement in English, all citations have been translated from Polish.
"Archived copy". Diarsipkan dari asli tanggal 2011-10-05. Diakses tanggal 2011-04-28. Pemeliharaan CS1: Salinan terarsip sebagai judul (link)
"Archived copy". Diarsipkan dari asli tanggal 2009-01-18. Diakses tanggal 2009-01-06. Pemeliharaan CS1: Salinan terarsip sebagai judul (link)
Wildlife Society Global Climate Change and Wildlife(PDF), diarsipkan dari asli(PDF) tanggal 2008-11-27 "Scientists throughout the world have concluded that climate research conducted in the past two decades definitively shows that rapid worldwide climate change occurred in the 20th century, and will likely continue to occur for decades to come. Although climates have varied dramatically since the Earth was formed, few scientists question the role of humans in exacerbating recent climate change through the emission of greenhouse gases. The critical issue is no longer "if" climate change is occurring, but rather how to address its effects on wildlife and wildlife habitats." The statement goes on to assert that "evidence is accumulating that wildlife and wildlife habitats have been and will continue to be significantly affected by ongoing large-scale rapid climate change." The statement concludes with a call for "reduction in anthropogenic (human-caused) sources of carbon dioxide and other greenhouse gas emissions contributing to global climate change and the conservation of CO2- consuming photosynthesizers (i.e., plants)."
World Federation of Public Health Associations resolution "Global Climate Change"(PDF), 2001, diarsipkan dari asli(PDF) tanggal 2008-12-17 "Noting the conclusions of the United Nations' Intergovernmental Panel on Climate Change (IPCC) and other climatologists that anthropogenic greenhouse gases, which contribute to global climate change, have substantially increased in atmospheric concentration beyond natural processes and have increased by 28 percent since the industrial revolution….Realizing that subsequent health effects from such perturbations in the climate system would likely include an increase in: heat-related mortality and morbidity; vector-borne infectious diseases,… water-borne diseases…(and) malnutrition from threatened agriculture….the World Federation of Public Health Associations…recommends precautionary primary preventive measures to avert climate change, including reduction of greenhouse gas emissions and preservation of greenhouse gas sinks through appropriate energy and land use policies, in view of the scale of potential health impacts...."
Statement supporting AGU statement on human-induced climate change, American Astronomical Society, 2004, diarsipkan dari asli tanggal 2007-05-07 "In endorsing the "Human Impacts on Climate" statement [issued by the American Geophysical Union], the AAS recognizes the collective expertise of the AGU in scientific subfields central to assessing and understanding global change, and acknowledges the strength of agreement among our AGU colleagues that the global climate is changing and human activities are contributing to that change."
