Intergovernmental Panel On Climate Change Methodology Research Articles

Assessment of Nitrous Oxide (N2O) Emissions from Farmland in 2011 with IPCC Guideline Methodology

This study was conducted to assess <TEX>$N_2O$</TEX> emissions in agricultural soils of Korea under the 1996 IPCC (Intergovernmental Panel on Climate Change) methodology. <TEX>$N_2O$</TEX> emissions in agricultural soils were calculated the sum of direct emission and indirect emission by the N sources and emissions by field burning of crop residues. <TEX>$N_2O$</TEX> emission was highest in animal manure as 1,547 <TEX>$CO_2$</TEX>-eq Gg. Indirect emissions by atmospheric deposition and leaching and runoff were 1,463 and 1,753 <TEX>$CO_2$</TEX>-eq Gg, respectively. <TEX>$N_2O$</TEX> emission by field burning of crop residues was highest in pepper due to the residue/crop ratio and field burning ratio.

Quantificação de biomassa e estocagem de carbono em uma floresta estacional semidecidual, no Parque Tecnológico de Viçosa, MG

Os objetivos deste trabalho foram quantificar a biomassa e a estocagem de carbono em uma Floresta Estacional Semidecidual,com área de 44,11 ha, localizado no Parque Tecnológico de Viçosa, MG e avaliar as diferenças entre as metodologias de quantificação de biomassa propostas pelo Painel Intergovernamental sobre Mudanças do Clima (IPCC) e utilizando equações regionais. Para a quantificação da biomassa e estocagem de carbono da área utilizou-se duas metodologias distintas, uma com equações regionais e outra sugerida pelo IPCC. Os estoques totais de biomassa e de carbono foram de 116,98 t ha-1 e 56,31 t ha-1,respectivamente, pela metodologia de equações regionais, considerando os valores acima e abaixo do solo, sub-bosque e serapilheira. E pela metodologia sugerida pelo IPCC, os estoques totais de biomassa e de carbono foram de 107,59 t ha-1 e 48,70 t ha-1, respectivamente. De acordo com os resultados a metodologia do IPCC subestimou a biomassa e o carbono em relação às equações regionais.

Global Sea Level Projections to 2100 Using Methodology of the Intergovernmental Panel on Climate Change

Forecasts of sea-level rise by 2100 have such a wide range that objective planning is difficult. In 2007, the Intergovernmental Panel on Climate Change (IPCC) forecast a sea-level rise from 1990 to 2100 between 0.18 and 0.59 m, but they did not completely consider contributions from Greenland and Antarctica in determining the upper limit. Recent projections by others have been larger, typically 1–2 m, with Greenland and Antarctica being the greatest contributors. However, these projections are usually maximum possible rises without probabilities of occurrence, whereas the maximum IPCC projection is at the 95% confidence level with a 2.5% probability of being equaled or exceeded. Project planning and design generally require projections with associated probabilities to determine risk. This paper shows what worldwide tide gauge data tell us about sea-level rise trends and accelerations in the twentieth century, and satellite altimeter recordings tell us about the rise since the early 1990s. Using IPCC methodology, sea level projections with associated probabilities are made from 1990 to 2100. Projections of Greenland and Antarctica contributions are estimated based on satellite measurements of current ice-mass-loss trends and accelerations, and then they are added to contributions from thermal expansion and melting of glaciers and ice caps based on the latest information. Sea-level rise projections from 1990 to 2100 are 0.18, 0.48, and 0.82 m at 5, 50, and 95% confidence levels, respectively.

2009년 우리나라 농경지 토양에서의 N2O 배출량 평가

우리나라 농경지에서의 <TEX>$N_2O$</TEX> 배출량을 1996과 2006 IPCC 방법론에 준하여 직접배출과 간접배출로 구분하여 산정하였다. 배출량 산정을 위한 활동자료는 농림수산식품부의 농림수산식품통계연보를 활용하였고, 배출계수는 1996 IPCC와 2006 IPCC에서 제시하고 있는 기본계수를 활용하였다. 직접배출량을 질소 투입원별로 산정한 결과 논과 밭에서 화학비료 시용에 의한 <TEX>$N_2O$</TEX> 배출량은 각각 159,579 <TEX>$CO_2$</TEX>-eq Mg과 976,460 <TEX>$CO_2$</TEX>-eq Mg이었고, 축산분뇨 시용에 따른 <TEX>$N_2O$</TEX> 배출량은 1,465,363 <TEX>$CO_2$</TEX>-eq Mg이었다. 두과작물의 질소 고정에 따른 <TEX>$N_2O$</TEX> 배출량은 52,395 <TEX>$CO_2$</TEX>-eq Mg이었고, 작물잔사 환원에 의한 <TEX>$N_2O$</TEX> 배출량은 14,562 <TEX>$CO_2$</TEX>-eq Mg 이었다. 간접배출에 의한 <TEX>$N_2O$</TEX> 배출량을 대기 유출과 수계 유출로 구분하여 산정된 양은 각각 1,415,881 <TEX>$CO_2$</TEX>-eq Mg과 1,864,043 Mg이었다. 우리나라 농경지의 <TEX>$N_2O$</TEX> 총배출량은 5,948,284 <TEX>$CO_2$</TEX>-eq Mg으로 직접배출량은 44.9%, 간접배출량은 55.1%를 차지하였으며, 경종부문 온실가스 전체 배출량의 48.7%를 점유하였다. This study was conducted to assess <TEX>$N_2O$</TEX> emissions in agricultural soils of Korea. According to 1996 and 2006 IPCC (Intergovernmental Panel on Climate Change) methodology, <TEX>$N_2O$</TEX> emission was calculated the sum of direct emission (<TEX>$N_2O_{DIRECT}$</TEX>) and indirect emission (<TEX>$N_2O_{INDIRECT}$</TEX>). To calculate <TEX>$N_2O$</TEX> emissions, emission factor was used default of IPCC and activity data was used the food, agricultural, forestry and fisheries statistical yearbook of MIFAFF (Ministry for Food, Agriculture, Forestry and Fisheries). It was emitted 8,608 <TEX>$N_2O$</TEX> Mg resulted from direct emission by application of chemical fertilizer and animal manure, input in n-fixation crops and input of crop residues and emissions converted <TEX>$N_2O$</TEX> into <TEX>$CO_2$</TEX> equivalent was 2,668 <TEX>$CO_2$</TEX>-eq Gg. Indirect emission as <TEX>$N_2O_{(G)}$</TEX> (atmospheric deposition of <TEX>$NH_3$</TEX> and <TEX>$NO_X$</TEX>) and <TEX>$N_2O_{(L)}$</TEX> (leaching and runoffs) were 4,567 and 6,013 <TEX>$N_2O$</TEX> Mg and emissions converted <TEX>$N_2O$</TEX> into <TEX>$CO_2$</TEX> equivalent were 1,416 and 1,864 <TEX>$CO_2$</TEX>-eq Gg, respectively. Total <TEX>$N_2O$</TEX> emission in Korea agricultural soil in 2009 was 5,948 <TEX>$CO_2$</TEX>-eq Gg.

Emissions of N2O from fertilized and grazed grassland on organic soil in relation to groundwater level

Intensively managed grasslands on organic soils are a major source of nitrous oxide (N2O) emissions. The Intergovernmental Panel on Climate Change (IPCC) therefore has set the default emission factor at 8 kg N–N2O ha−1 year−1 for cultivation and management of organic soils. Also, the Dutch national reporting methodology for greenhouse gases uses a relatively high calculated emission factor of 4.7 kg N–N2O ha−1 year−1. In addition to cultivation, the IPCC methodology and the Dutch national methodology account for N2O emissions from N inputs through fertilizer applications and animal urine and faeces deposition to estimate annual N2O emissions from cultivated and managed organic soils. However, neither approach accounts for other soil parameters that might control N2O emissions such as groundwater level. In this paper we report on the relations between N2O emissions, N inputs and groundwater level dynamics for a fertilized and grazed grassland on drained peat soil. We measured N2O emissions from fields with different target groundwater levels of 40 cm (‘wet’) and 55 cm (‘dry’) below soil surface in the years 1992, 1993, 2002, 2006 and 2007. Average emissions equalled 29.5 kg N2O–N ha−1 year−1 and 11.6 kg N–N2O ha−1 year−1 for the dry and wet conditions, respectively. Especially under dry conditions, measured N2O emissions exceeded current official estimates using the IPCC methodology and the Dutch national reporting methodology. The N2O–N emissions equalled 8.2 and 3.2% of the total N inputs through fertilizers, manure and cattle droppings for the dry and wet field, respectively and were strongly related to average groundwater level (R 2 = 0.74). We argue that this relation should be explored for other sites and could be used to derive accurate emission data for fertilized and grazed grasslands on organic soils.

Greenhouse gas emissions from the Canadian beef industry

Commodity-specific estimates of the greenhouse gas (GHG) emissions from Canadian agriculture are required in order to identify the most efficient GHG mitigation measures. In this paper, the methodology from the Intergovernmental Panel on Climate Change (IPCC) for estimating bovine GHG emissions, for census years from 1981 to 2001, was applied to the Canadian beef industry. This analysis, which is based on several adaptations of IPCC methodology already done for the Canadian dairy industry, includes the concept of a beef crop complex, the land base that feeds the beef population, and the use of recommendations for livestock feed rations and fertilizer application rates to down-scale the national area totals of each crop, regardless of the use of that crop, to the feed requirements of the Canada’s beef population. It shows how high energy feeds are reducing enteric methane emissions by displacing high roughage diets. It also calculates an emissions intensity indicator based on the total weight of live beef cattle destined for market. While total GHG from Canadian beef production have increased from 25 to 32 Tg of CO 2 equiv. between 1981 and 2001, this increase was mainly driven by expansion of the Canadian cattle industry. The emission intensity indicator showed that between 1981 and 2001, the Canadian beef industry GHG emissions per kg of live animal weight produced for market decreased from 16.4 to 10.4 kg of CO 2 equiv.

The production and emission of nitrous oxide from headwater streams in the Midwestern United States

AbstractThe emission of nitrous oxide (N2O) from streams draining agricultural landscapes is estimated by the Intergovernmental Panel on Climate Change (IPCC) to constitute a globally significant source of this gas to the atmosphere, although there is considerable uncertainty in the magnitude of this source. We measured N2O emission rates and potential controlling variables in 12 headwater streams draining a predominantly agricultural basin on glacial terrain in southwestern Michigan. The study sites were nearly always supersaturated with N2O and emission rates ranged from −8.9 to 266.8 μg N2O‐N m−2 h−1 with an overall mean of 35.2 μg N2O‐N m−2 h−1. Stream water NO3− concentrations best‐predicted N2O emission rates. Although streams and agricultural soils in the basin had similar areal emission rates, emissions from streams were equivalent to 6% of the anthropogenic emissions from soils because of the vastly greater surface area of soils. We found that the default value of the N2O emission factor for streams and groundwater as defined by the IPCC (EF5‐g) was similar to the value observed in this study lending support to the recent downward revision to EF5‐g. However, the EF5‐g spanned four orders of magnitude across our study sites suggesting that the IPCC's methodology of applying one emission factor to all streams may be inappropriate.

Diurnal fluctuations of dissolved nitrous oxide (N2O) concentrations and estimates of N2O emissions from a spring‐fed river: implications for IPCC methodology

AbstractThere is uncertainty in the estimates of indirect nitrous oxide (N2O) emissions as defined by the Intergovernmental Panel on Climate Change (IPCC). The uncertainty is due to the challenge and dearth of in situ measurements. Recent work in a subtropical stream system has shown the potential for diurnal variability to influence the downstream N transfer, N form, and estimates of in‐stream N2O production. Studies in temperate stream systems have also shown diurnal changes in stream chemistry.The objectives of this study were to measure N2O fluxes and dissolved N2O concentrations from a spring‐fed temperate river to determine if diurnal cycles were occurring. The study was performed during a 72 h period, over a 180 m reach, using headspace chamber methodology. Significant diurnal cycles were observed in radiation, river temperature and chemistry including dissolved N2O‐N concentrations. These data were used to further assess the IPCC methodology and experimental methodology used. River NO3‐N and N2O‐N concentrations averaged 3.0 mg L−1 and 1.6 μg L−1, respectively, with N2O saturation reaching a maximum of 664%. The N2O‐N fluxes, measured using chamber methodology, ranged from 52 to 140 μg m−2 h−1 while fluxes predicted using the dissolved N2O concentration ranged from 13 to 25 μg m−2 h−1. The headspace chamber methodology may have enhanced the measured N2O flux and this is discussed. Diurnal cycles in N2O% saturation were not large enough to influence downstream N transfer or N form with variability in measured N2O fluxes greater and more significant than diurnal variability in N2O% saturation. The measured N2O fluxes, extrapolated over the study reach area, represented only 6 × 10−4% of the NO3‐N that passed through the study reach over a 72 h period. This is only 0.1% of the IPCC calculated flux.

Estimates of direct nitrous oxide emissions from Canadian agroecosystems and their uncertainties

Using a revised Intergovernmental Panel on Climate Change (IPCC) methodology and the process-based model DeNitrification and DeComposition (DNDC), we estimated N2O emissions from agroecosystems in Canada for each census year from 1981 to 2001. Based on the IPCC methodology, direct emissions of N2O ranged from 12.9 to 17.3 with an average of 15.1 Tg CO2 equivalents, while the DNDC model predicted values from 16.0 to 24.3 with an average of 20.8 Tg CO2 equivalents over the same period, and showed a large interannual variation reflecting weather variability. On a provincial basis, emissions estimated by IPCC and DNDC methods were highest in Alberta, Saskatchewan and Ontario, intermediate for Manitoba and Quebec and lowest in British Columbia and the Atlantic provinces. The greatest source of emissions estimated by the IPCC method was from N fertilizer (avg. 6.32 Tg CO2 equiv. in Canada), followed by crop residues (4.24), pasture range and paddocks (PRP) (2.77), and manure (1.65). All sources of emissions, but especially those from fertilizers, increased moderately over time. Monte Carlo Simulation was used to determine the uncertainty associated with the 2001 emission estimates for both IPCC and DNDC methodologies. The simulation generated most likely values of 19.2 and 16.0 Tg CO2 equivalents for IPCC and DNDC, respectively, with uncertainties of 37 and 41%, respectively. Values for the IPCC estimates varied between 28% for PRP and manure and 50% for N fertilizer and crop residues. At the provincial level, uncertainty ranged between 15 and 47% with higher values on the prairies. Sensitivity analyses for IPCC estimates showed crop residues as the most important source of uncertainty followed by synthetic N-fertilizers. Our analysis demonstrated that N2O emissions can be effectively estimated by both the DNDC and IPCC methods and that their uncertainties can be effectively estimated by Monte Carlo Simulation. Key words: Nitrous oxide, IPCC, DNDC model, Uncertainty analysis, Monte Carlo Simulation

DAYCENT National‐Scale Simulations of Nitrous Oxide Emissions from Cropped Soils in the United States

Until recently, Intergovernmental Panel on Climate Change (IPCC) emission factor methodology, based on simple empirical relationships, has been used to estimate carbon (C) and nitrogen (N) fluxes for regional and national inventories. However, the 2005 USEPA greenhouse gas inventory includes estimates of N2O emissions from cultivated soils derived from simulations using DAYCENT, a process-based biogeochemical model. DAYCENT simulated major U.S. crops at county-level resolution and IPCC emission factor methodology was used to estimate emissions for the approximately 14% of cropped land not simulated by DAYCENT. The methodology used to combine DAYCENT simulations and IPCC methodology to estimate direct and indirect N2O emissions is described in detail. Nitrous oxide emissions from simulations of presettlement native vegetation were subtracted from cropped soil N2O to isolate anthropogenic emissions. Meteorological data required to drive DAYCENT were acquired from DAYMET, an algorithm that uses weather station data and accounts for topography to predict daily temperature and precipitation at 1-km2 resolution. Soils data were acquired from the State Soil Geographic Database (STATSGO). Weather data and dominant soil texture class that lie closest to the geographical center of the largest cluster of cropped land in each county were used to drive DAYCENT. Land management information was implemented at the agricultural-economic region level, as defined by the Agricultural Sector Model. Maps of model-simulated county-level crop yields were compared with yields estimated by the USDA for quality control. Combining results from DAYCENT simulations of major crops and IPCC methodology for remaining cropland yielded estimates of approximately 109 and approximately 70 Tg CO2 equivalents for direct and indirect, respectively, mean annual anthropogenic N2O emissions for 1990-2003.

Towards a Revised Coefficient for Estimating N2O Emissions from Legumes

The Intergovernmental Panel on Climate Change (IPCC) standard methodology to conduct national inventories of soil N2O emissions is based on default (or Tier I) emission factors for various sources. The objective of our study was to summarize recent N2O flux data from agricultural legume crops to assess the emission factor associated with rhizobial nitrogen fixation. Average N2O emissions from legumes are 1.0 kg N ha−1 for annual crops, 1.8 kg N ha−1 for pure forage crops and 0.4 kg N ha−1 for grass legume mixes. These values are only slightly greater than background emissions from agricultural crops and are much lower that those predicted using 1996 IPCC methodology. These field flux measurements and other process-level studies offer little support for the use of an emission factor for biological N fixation (BNF) by legume crops equal to that for fertiliser N. We conclude that much of the increase in soil N2O emissions in legume crops may be attributable to the N release from root exudates during the growing season and from decomposition of crop residues after harvest, rather than from BNF per se. Consequently, we propose that the biological fixation process itself be removed from the IPCC N2O inventory methodology, and that N2O emissions induced by the growth of legume crops be estimated solely as a function of crop residue decomposition using an estimate of above- and below-ground residue inputs, modified as necessary to reflect recent findings on N allocation.

The treatment of long-lived, carbon-containing products in inventories of carbon dioxide emissions to the atmosphere

The United Nations Framework Convention on Climate Change (UNFCCC) requires that all parties to the convention periodically report their emissions of greenhouse gases and the Intergovernmental Panel on Climate Change (IPCC) has published guidelines on how to estimate these emissions. Estimating carbon dioxide (CO2) emissions is complicated by the fact that consumption of fossil-fuels and harvesting of forests do not necessarily mean that the contained C has been released to the atmosphere as CO2. Some fractions of fossil-fuels and harvested wood are incorporated into products that have lifetimes ranging from months to centuries. The IPCC methodology addresses durable products by assuming that some prescribed fraction goes to permanent storage while the remainder is oxidized instantly. The question posed here is whether the annual increase in stocks of durable products, i.e. the difference between the rates of production and oxidation, can be reasonably estimated as a simple fraction of their current rate of production. Although the annual stock change can be described as a simple fraction of annual production when production is growing exponentially and oxidation is a first order decay process, a description of annual stock changes needs to consider how both production and oxidation are evolving with time, regardless of the functional forms of these changes with time.

Inventory of nitrous oxide emissions from agriculture in Belgium - calculations according to the revised 1996 Intergovernmental Panel on Climate Change guidelines

In this study an inventory of N2O emissions from agriculture in Belgium was made according to the Intergovernmental Panel on Climate Change (IPCC) guidelines. Three sources of N2O were distinguished between: (1) direct N2O emissions from agricultural soils (N2O-direct), (2) N2O emissions due to animal production systems (N2O-animals), and (3) indirect N2O emissions as a result of N losses from agricultural soils (N2O-indirect). In 1996, the total N2O emission from agriculture in Belgium was 12.8×106 kg N2O-N. N2O-direct, N2O-animals and N2O-indirect contributed 60%, 7% and 33%, respectively, to the total N2O emission. The IPCC methodology tended to give an overestimate of the N2O emission from agriculture by 45% when IPCC default values were used instead of country-specific N-input data. Between 1950 and 1996, the total N2O emission from agriculture in Belgium increased from 8.4×106 kg N2O-N to 12.8×106 kg N2O-N. This was an increase of 53%, or about 0.1×106 kg N2O-N-year–1.

Methane Emissions from Domestic Waste Management Facilities in Jordan—Applicability of IPCC Methodology

ABSTRACT In this paper, methane emissions from municipal wastewater treatment plants and municipal solid waste (MSW) landfills in Jordan for 1994 have been estimated using the methodology developed by the Intergovernmental Panel on Climate Change (IPCC). For this purpose, the 14 domestic wastewater treatment plants in the country were surveyed. Generation rates and characterization of MSW components as well as dumping and landfilling practices were surveyed in order to estimate 1994 CH4 emissions from these sites. Locally available waste statistics were used in cases where those of the IPCC guidelines were not representative of Jordan's statistics. Methane emissions from domestic wastewater in Jordan were estimated at 4.66 gigagrams (Gg). Total 1994 CH4 emissions from MSW management facilities in Jordan are estimated at 371.76 Gg—351.12 Gg (94.45%) from sanitary landfills, 19.83 Gg (5.33%) from MSW open dumps, and 0.81 Gg (0.22%) from raw sewage-water dumping ponds. Uncertainties associated with these estimations are presented.