The Paris Agreement proposed to keep the increase in global average temperature to well below 2 ℃ abovepre-industrial levels and to pursue efforts to limit the temperature increase to 1.5 ℃ above pre-industriallevel...The Paris Agreement proposed to keep the increase in global average temperature to well below 2 ℃ abovepre-industrial levels and to pursue efforts to limit the temperature increase to 1.5 ℃ above pre-industriallevels. It was thus the first international treaty to endow the 2 ℃ global temperature target with legal effect.The qualitative expression of the ultimate objective in Article 2 of the United Nations Framework Conventionon Climate Change （UNFCCC） has now evolved into the numerical temperature rise target in Article 2 of theParis Agreement. Starting with the Second Assessment Report （SAR） of the Intergovernmental Panel on Cli-mate Change （IPCC）, an important task for subsequent assessments has been to provide scientific informa-tion to help determine the quantified long-term goal for UNFCCC negotiation. However, due to involvementin the value judgment within the scope of non-scientific assessment, the IPCC has never scientifically af-firmed the unacceptable extent of global temperature rise. The setting of the long-term goal for addressingclimate change has been a long process, and the 2 ℃ global temperature target is the political consensuson the basis of scientific assessment. This article analyzes the evolution of the long-term global goal foraddressing climate change and its impact on scientific assessment, negotiation processes, and global low-carbon development, from aspects of the origin of the target, the series of assessments carried out by the 1PCCfocusing on Article 2 of the UNFCCC, and the promotion of the global temperature goal at the political level.展开更多
Carbon footprint analysis is a method to quantify the life cycle Greenhouse Gases (GHGs) emissions and identify the measure to reduce climate change impacts. The Intergovernmental Panel on Climate Change (IPCC) has id...Carbon footprint analysis is a method to quantify the life cycle Greenhouse Gases (GHGs) emissions and identify the measure to reduce climate change impacts. The Intergovernmental Panel on Climate Change (IPCC) has identified that the global warming and climate change which is one of the most important issues in the domain of environment are caused by the excessive emission of Greenhouse Gases (GHG) mainly constituting Carbon dioxide (CO2), Methane (CH4) and Nitrous oxide (N2O). The municipal wastewater treatment plant receives wastewater for treatment and finally discharges the treated effluent. The emissions of GHG during the treatment of wastewater as well as during the treatment process of sludge and also for energy generation are known to be on-site GHG emissions. Off-site GHG emissions are generated due to transportation and disposal of sludge, off-site energy and chemical production. In Puducherry, the municipal wastewater is being treated using oxidation ponds, Upflow Anaerobic Sludge Blanket (UASB) and Sequencing Batch Reactor (SBR). Wastewater treatment using Sequencing Batch Reactor (SBR) technology is one of the state-of-the art wastewater management systems. In this technology equalization, biological treatment and secondary clarification are performed in a single reactor in a time control sequence. The emissions of GHG from the Oxidation ponds of 12.5 MLD, UASB reactor of 2.5 MLD and SBR of 17 MLD were assessed based on the IPCC guidelines and the total emissions of GHG in terms of equivalent of CO2 were compared. The performance of the SBR is more efficient and the emissions of GHG are less than the emissions in the UASB as well as in oxidation ponds. The emission of GHG in SBR is about 60% of the existing treatment systems of oxidation ponds and UASB thus a reduction of 40% GHG emission could be achieved.展开更多
气候变化问题是当今国际社会普遍关注的全球性环境问题之一.全球应对气候变化不仅涉及科学问题,也是国际政治经济共同涉及的问题.政府间气候变化专门委员会（Intergovernmental Panel on Climate Change,IPCC）通过汇总评估全球范围内...气候变化问题是当今国际社会普遍关注的全球性环境问题之一.全球应对气候变化不仅涉及科学问题,也是国际政治经济共同涉及的问题.政府间气候变化专门委员会（Intergovernmental Panel on Climate Change,IPCC）通过汇总评估全球范围内气候变化领域的最新研究成果.展开更多
Climate change has attracted significant attention due to its increasing impacts on various aspects of the world,and future climate projections are of vital importance for associated adaptation and mitigation,particul...Climate change has attracted significant attention due to its increasing impacts on various aspects of the world,and future climate projections are of vital importance for associated adaptation and mitigation,particularly at the regional scale.However,the skill level of the model projections over China in the past more than ten years remains unknown.In this study,we retrospectively investigate the skill of climate models within the Third(TAR),Fourth(AR4),and Fifth(AR5)Assessment Reports of the Intergovernmental Panel on Climate Change(IPCC)for the near-term projections of near-surface(2 m)air temperature changes in China.Those models are revealed to be skillful in projecting the subsequent climatology and trend of the temperature changes in China during 2002-2018 from several to ten years ahead,with higher scores for the climatology than for the trend.The model projections display cold biases against observations in most of China,while the nationally averaged trend is overestimated by TAR models during 2002-2018 but underestimated by AR4 models during 2008-2018.For all emission scenarios,there is no obvious difference between the equal-and unequal-weighted averages based on the arithmetic averaging and reliability ensemble averaging method respectively,however the uncertainty range of projection is narrowed after weighting.The near-term temperature projections differ slightly among various emission scenarios for the climatology but are largely different for the trend.展开更多
文摘The Paris Agreement proposed to keep the increase in global average temperature to well below 2 ℃ abovepre-industrial levels and to pursue efforts to limit the temperature increase to 1.5 ℃ above pre-industriallevels. It was thus the first international treaty to endow the 2 ℃ global temperature target with legal effect.The qualitative expression of the ultimate objective in Article 2 of the United Nations Framework Conventionon Climate Change （UNFCCC） has now evolved into the numerical temperature rise target in Article 2 of theParis Agreement. Starting with the Second Assessment Report （SAR） of the Intergovernmental Panel on Cli-mate Change （IPCC）, an important task for subsequent assessments has been to provide scientific informa-tion to help determine the quantified long-term goal for UNFCCC negotiation. However, due to involvementin the value judgment within the scope of non-scientific assessment, the IPCC has never scientifically af-firmed the unacceptable extent of global temperature rise. The setting of the long-term goal for addressingclimate change has been a long process, and the 2 ℃ global temperature target is the political consensuson the basis of scientific assessment. This article analyzes the evolution of the long-term global goal foraddressing climate change and its impact on scientific assessment, negotiation processes, and global low-carbon development, from aspects of the origin of the target, the series of assessments carried out by the 1PCCfocusing on Article 2 of the UNFCCC, and the promotion of the global temperature goal at the political level.
文摘Carbon footprint analysis is a method to quantify the life cycle Greenhouse Gases (GHGs) emissions and identify the measure to reduce climate change impacts. The Intergovernmental Panel on Climate Change (IPCC) has identified that the global warming and climate change which is one of the most important issues in the domain of environment are caused by the excessive emission of Greenhouse Gases (GHG) mainly constituting Carbon dioxide (CO2), Methane (CH4) and Nitrous oxide (N2O). The municipal wastewater treatment plant receives wastewater for treatment and finally discharges the treated effluent. The emissions of GHG during the treatment of wastewater as well as during the treatment process of sludge and also for energy generation are known to be on-site GHG emissions. Off-site GHG emissions are generated due to transportation and disposal of sludge, off-site energy and chemical production. In Puducherry, the municipal wastewater is being treated using oxidation ponds, Upflow Anaerobic Sludge Blanket (UASB) and Sequencing Batch Reactor (SBR). Wastewater treatment using Sequencing Batch Reactor (SBR) technology is one of the state-of-the art wastewater management systems. In this technology equalization, biological treatment and secondary clarification are performed in a single reactor in a time control sequence. The emissions of GHG from the Oxidation ponds of 12.5 MLD, UASB reactor of 2.5 MLD and SBR of 17 MLD were assessed based on the IPCC guidelines and the total emissions of GHG in terms of equivalent of CO2 were compared. The performance of the SBR is more efficient and the emissions of GHG are less than the emissions in the UASB as well as in oxidation ponds. The emission of GHG in SBR is about 60% of the existing treatment systems of oxidation ponds and UASB thus a reduction of 40% GHG emission could be achieved.
基金supported by the National Natural Science Foundation of China(41991284)the Second Tibetan Plateau Scientific Expedition and Research Program(2019QZKK0101)+1 种基金the National Key Research and Development Program of China(2018YFA0606501)the National Key Scientific and Technological Infrastructure Project“Earth System Science Numerical Simulator Facility”(Earth Lab)。
文摘Climate change has attracted significant attention due to its increasing impacts on various aspects of the world,and future climate projections are of vital importance for associated adaptation and mitigation,particularly at the regional scale.However,the skill level of the model projections over China in the past more than ten years remains unknown.In this study,we retrospectively investigate the skill of climate models within the Third(TAR),Fourth(AR4),and Fifth(AR5)Assessment Reports of the Intergovernmental Panel on Climate Change(IPCC)for the near-term projections of near-surface(2 m)air temperature changes in China.Those models are revealed to be skillful in projecting the subsequent climatology and trend of the temperature changes in China during 2002-2018 from several to ten years ahead,with higher scores for the climatology than for the trend.The model projections display cold biases against observations in most of China,while the nationally averaged trend is overestimated by TAR models during 2002-2018 but underestimated by AR4 models during 2008-2018.For all emission scenarios,there is no obvious difference between the equal-and unequal-weighted averages based on the arithmetic averaging and reliability ensemble averaging method respectively,however the uncertainty range of projection is narrowed after weighting.The near-term temperature projections differ slightly among various emission scenarios for the climatology but are largely different for the trend.
