Fixing carbon: To alleviate climate change, scientists are exploring ways to harness nature's ability to capture CO2 from the atmosphere.

Operationalizing marketable blue carbon

Twenty-first century sea-level rise could exceed IPCC projections for strong-warming futures

Introduction to <i>Climate Change Adaptation in New York City: Building a Risk Management Response</i>

گرمایش جهانی و به‌تبع آن تغییر اقلیم، موضوع مهمی است که در دهه‌های اخیر توسط محققین در سرتاسر دنیا موردمطالعه قرارگرفته است. در این مطالعات تغییرات پارامترهای اقلیمی موردبررسی قرار می‌گیرد. با توجه به عدم قطعیت فراوان دخیل در برآورد این پارامترها، بهتر است شیوه‌ای اتخاذ گردد تا تحلیل‌ها با بررسی باند ناشی از منابع مختلف عدم قطعیت، صورت پذیرد. بدین منظور در این مطالعه تلاش شد با بررسی باند عدم قطعیت ناشی از 15 مدل AOGCM تحت تأثیر سه سناریو انتشار A1B، A2 و B1 به بررسی تغییرات پارامترهای حداقل دما، حداکثر دما و بارندگی در ایستگاه سینوپتیک مشهد واقع در حوضه قره قوم پرداخته شود. از مدل LARS-WG به منظور ریزمقیاس نمایی استفاده گردید. توانایی بالای مدل LARS-WG در شبیه‌سازی پارامترهای اقلیمی در دوره پایه تأیید شد؛ به‌طوری‌که مقادیر مدل نسبت به مقادیر مشاهده‌شده در تمامی ماه‌ها دقت خوبی را دارا بوده است. نتایج حاکی از وجود بیشترین باند عدم قطعیت در برآوردهای مربوط به سناریو A1B بود، ولی در مورد کمترین باند عدم قطعیت در مورد پارامترهای مختلف نتایج متفاوتی به دست آمد که برای حداقل دما و بارندگی سناریو B1 و برای حداکثر دما سناریو A2 معرفی گردید.

Better information on greenhouse gas (GHG) emissions and mitigation potential in the agricultural sector is necessary to manage these emissions and identify responses that are consistent with the food security and economic development priorities of countries. Critical activity data (what crops or livestock are managed in what way) are poor or lacking for many agricultural systems, especially in developing countries. In addition, the currently available methods for quantifying emissions and mitigation are often too expensive or complex or not sufficiently user friendly for widespread use.The purpose of this focus issue is to capture the state of the art in quantifying greenhouse gases from agricultural systems, with the goal of better understanding our current capabilities and near-term potential for improvement, with particular attention to quantification issues relevant to smallholders in developing countries. This work is timely in light of international discussions and negotiations around how agriculture should be included in efforts to reduce and adapt to climate change impacts, and considering that significant climate financing to developing countries in post-2012 agreements may be linked to their increased ability to identify and report GHG emissions (Murphy et al 2010, CCAFS 2011, FAO 2011).

CR Climate Research Contact the journal Facebook Twitter RSS Mailing List Subscribe to our mailing list via Mailchimp HomeLatest VolumeAbout the JournalEditorsSpecials CR 10:155-162 (1998) - doi:10.3354/cr010155 The IPCC future projections: are they plausible? Vincent Gray* Climate Consultant, 75 Silverstream Road, Crofton Downs, Wellington 6004, New Zealand *E-mail: vincegray@xtra.co.nz ABSTRACT: IPCC (Intergovernmental Panel on Climate Change) future projections are based on a set of emission scenarios, IS92a to f, which are used to calculate future atmospheric concentrations of greenhouse gases. These, in turn, are used to calculate projections of radiative forcing, and then projections of future temperature and sea level change to the year 2100, using computer climate models. The assumptions of these 6 IPCC emission scenarios for the years 1995 and 2000 are compared with currently available information on greenhouse gas emissions, world population trends, and trends in world coal production. All of the scenarios exaggerate one or more of these quantities. Calculations of confidence limits on the net human-induced contribution of carbon dioxide to the atmosphere show a very high level of inaccuracy. When added to the even greater uncertainties connected with assumptions on the main greenhouse gas, water vapour, and also on clouds, plus the uncertainties of the computer models themselves, the current IPCC future projections of global temperature and sea level must be regarded as extremely unreliable. Fossil fuel emissions assumed by the IPCC scenarios for the year 2000 are plausible for scenarios IS92a, b, c and d, but not for e and f. The calculated rate of increase of atmospheric carbon dioxide concentration since 1990 assumed by the IPCC is exaggerated by 13% for all scenarios. The calculated rates of increase in atmospheric methane from 1990 to 2000 are exaggerated by 3 to 7 times, world population increases by up to 5.5%, and world coal production increases by 60 to 510%. The rate of increase of carbon dioxide in the atmosphere has been almost constant, at 0.4% a year, between 1971 and 1996, despite a 54% increase in emissions from the combustion of fossil fuels over that period. Currently suggested reductions from present emission levels are therefore unlikely to influence carbon dioxide concentrations, or global temperatures. Since all of the IS92 scenarios exaggerate one or more current climate and economic trends, the calculated future projections of atmospheric greenhouse gas concentrations are thus correspondingly exaggerated. A more realistic set of scenarios, which would include a mechanism for continuous updating, needs to be developed, thus scaling down the current values. Even if this is done, however, the accumulated inaccuracies inherent in the final calculations of climatic effects are so great as to render them unreliable as a guide to public policy. KEY WORDS: Climate change · Intergovernmental Panel on Climate Change · Emission scenarios Full text in pdf format PreviousExport citation RSS - Facebook - Tweet - linkedIn Cited by Published in CR Vol. 10, No. 2. Online publication date: August 14, 1998 Print ISSN: 0936-577X; Online ISSN: 1616-1572 Copyright © 1998 Inter-Research.

Boykoff and Mansfield (2008), in a recent paper in this journal, provide a detailedanalysis of the representation of climate change in the UK tabloid newspapers.They conclude that the representation of this issue in these papers ‘diverged fromthe scientific consensus that humans contribute to climate change’. That is,portrayal of climate change in tabloid newspapers contradicts the conclusions ofthe fourth Intergovernmental Panel on Climate Change (IPCC) assessment (IPCC2007). Is it healthy to have the scientific consensus challenged so frequently? Butshould we worry about systematic misrepresentation of scientific consensus? Webelieve the answer to both of these questions is yes. To present regular updates onclimate change issues in the popular press is important because the changes inbehaviour needed to achieve substantial reductions in greenhouse gas emissionsrequire a broad understanding of the basic facts. However, if the majority ofreaders receive misleading information, it will be difficult to achieve the level ofpublic understanding necessary to make such reductions needed to avoiddangerous climate change (Schellnhuber

Communicating Uncertainty about Climate Change: The Scientists’ Dilemma

Climate change is already happening in the world today. Global warming leading to melting of polar icebergs and snow covers is seen today and causes the sea level to rise. Extreme weather conditions have also become the new norms. Consequently, life on earth is affected, mostly with negative outcomes. Human activities that emit three primary greenhouse gases (GHG), namely carbon dioxide, methane and nitrous oxide are found to be the principal causes of climate change. As such, there is an urgent need for concerted efforts by mankind to limit and abate the emission of these gases in order to slow down climate change. At the international level, Intergovernmental Panel on Climate Change (IPCC) which is a UN based institution, has been setting up policies and actions to abate climate change. It is presently coordinating actions to limit a global temperature rise to below 1.5oC. Malaysia is a signatory to the United Nations Framework Convention on Climate Change (UNFCCC) climate treaty in 1992 and is doing her part to contribute to this agenda. In this respect, Malaysia has pledged to maintain at least 50 per cent of the landmass perpetually under forest cover. Malaysia also pledged to reduce the GHG emissions intensity of Gross Domestic Product (GDP) by 45 per cent by 2030 relative to the emissions intensity of GDP in 2005 for the country at COP21 (Conference of Parties) in 2015. Keywords: Climate change, greenhouse gas, global warming, sea level rise, El Nino, Intergovernmental Panel on Climate Change

Climate-change crunch time

A Closer Look at the IPCC Report

An attempt was made to statistically explain the yearly increased rate of atmospheric carbon dioxide accumulation by means of the yearly emissions of anthropogenic carbon dioxide and the global mean temperature using data from the period 1980–2007. It is commonly assumed (e.g. by the UN Intergovernmental Panel on Climate Change; IPCC) that a part of the emitted carbon dioxide will stay in the atmosphere and, therefore, large emission rate of carbon dioxide should cause large increase rate of atmospheric carbon dioxide. High temperature should also increase the atmospheric carbon dioxide concentration due to lowered solubility of carbon dioxide in the backmixed ocean surface water. However, using two-dimensional regression analysis, the increase rate could not be explained by the emissions because temperature was the dominating parameter that controlled the increase rate. The fraction of the emissions that remained in the atmosphere—or the airborne fraction—decreased significantly despite global warming. This may be explained by increased diffusion or sink flow to the biosphere and the oceans due to increased atmospheric partial pressure of carbon dioxide.

Methane emissions along biomethane and biogas supply chains are underestimated

Global climate change: Lessons from the past – policy for the future

So far, the climate on the Earth, from beginning to end, has been changing, making in circle and not stopping. About this point, the specialists seemly have no disagreement. However, About causes of climate change, they indeed have divergence, and as for whether carbon dioxide is or not main cause of global climate warming, their divergence is much more large. Some specialists considered that natural factors are main causes led to climate change, and influence of anthropological factors on climate change is very very small. However, the other specialists considered that anthropological factors are important cause led to climate change, and also emission of greenhouse gases is main causes led to climate warming and at which, emission of carbon dioxide is the most main cause led to global climate warming. Still also some specialists consisted that carbon dioxide emitted by human activities is a chief culprit led to global warming. The Intergovernmental Panel on Climate Change (IPCC) stated that the climate on the Earth is warming. Emission of greenhouse gases led to climate warming, and carbon dioxide is main cause led to climate warming, and especially the carbon dioxide emitted by human activities is the most main cause led to global warming. Now, the climate on the earth is getting more and more warming. If the people did not control emission of carbon dioxide, the global climate warming would bring ecological cataclysm to the mankind. The climate change theory described by IPCC is called “Global warming” theory, or “Greenhouse effect” theory. The global warming theory, or greenhouse effect theory, has had very large influence on the all over the world. In China, also there are a lot of people who believe that “global warming” is true, is right and is scientific. Especially in Chinese academic circles, there are many specialists who especially believe “global warming”, and they forcefully trumpeted that the global climate is getting more and more warming. The carbon dioxide was considered as a chief culprit resulted led to global warming. Still also there are some people who placed “ global warming” theory on the god altar, and accepted some people to prostrate themselves in worship. The “Global warming” theory put forward by IPCC, at home and abroad, all has received a lot of serious criticism. According to basic theory of classical physics and basic fact of climate observation, we can prove that emission of greenhouse gases is not main cause led to climate change, and also carbon dioxide is not most main cause led to climate warming, and still also carbon dioxide emitted by human activities was not a chief culprit led to global warming. Thus, large decrease of emission of carbon dioxide cannot control the greenhouse effect, and also cannot prevent climate warming, and still also cannot stop happening of climate cataclysm.