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北京市和厦门市大气 CO2 浓度及 δ13C 值变化特征
大气 CO2 浓度 δ13C 季节变化 昼夜变化 Keeling 曲线
2019/1/16
本文对北京市和厦门市大气CO2及 δ13C进行观测，研究内陆城市和沿海城市CO2浓度及 δ13C的季节和昼夜变化规律及影响因素，以期为政府制定碳减排政策提供科学依据。北京市和厦门市CO2浓度均呈现秋冬季高于春夏季，而 δ13C秋冬季低于春夏季，季节差异原因可能是秋冬大气边界层降低，化石燃料消耗增加，贫13C的CO2气体大量排放。观测期间，两个城市日变化模式均表现为CO2夜间高于白天， δ13C夜间...
Analysis of 13C and 18O isotope data of CO2 in CARIBIC aircraft samples as tracers of upper troposphere/lower stratosphere mixing and the global carbon cycle
13C and 18O isotope data CO2 CARIBIC aircraft samples the global carbon cycle
2010/9/21
The project CARIBIC (http://caribic-atmospheric.com) aims to study atmospheric chemistry and transport by regularly measuring many compounds in the free troposphere and the upper troposphere/lowermost...
Climate and CO2 modulate the C3/C4 balance and δ13C signal in simulated vegetation
Climate and CO2 modulate δ13C signal C3/C4 balance
2009/12/3
Climate and atmospheric CO2 effects on the balance between C3 and C4 plants have received conflicting interpretations based on the analysis of carbon isotopic fractionation (δ13C) in sediments. But, c...
Climate reconstruction from pollen and δ13C records using inverse vegetation modeling – Implication for past and future climates
Climate reconstruction future climates
2009/12/3
An improved inverse vegetation model has been designed to better specify both temperature and precipitation estimates from vegetation descriptions. It is based on the BIOME4 vegetation model and uses...
针对IPCC评估报告中海洋碳循环的疑问--δ13C收支平衡法的验证
IPCC CO2收支 δ 13C 同位素分馏
2009/8/28
通过对比IPCC历次评估报告中全球碳循环的收支发现，尽管评估报告在估算各主要碳库及其间的通量时差别不大，但表层至中深层海水间溶解无机碳通量却存在巨大差异。利用δ13C的收支平衡检验了这一通量的适用范围，结果表明：IPCC 1996年和2007年评估报告对此通量估计过大，而1990年和2001年评估报告估计偏小。
Using 14C, 13C, 18O and 17O isotopic variations to provide insights into the high northern latitude surface CO inventory
14C 13C 18O and 17O isotopic variations high northern latitude CO
2009/3/12
Measurements of the complete isotopic composition of atmospheric CO (3CO, 14CO, C17O, C18O) have been carried out at the high northern latitude stations Spitsbergen, Norway, and Alert, Canada. The ann...
Hemispheric average Cl atom concentration from 13C/12C ratios in atmospheric methane
Hemispheric average Cl atom concentration 13C/12C ratios atmospheric methane
2009/3/10
Methane is a significant atmospheric trace gas in the context of greenhouse warming and climate change. The dominant sink of atmospheric methane is the hydroxyl radical (OH). Recently, a mechanism for...
Arguments on Oceanic Carbon Cycle of IPCC Assessments——A Test Using δ13C Budgets
IPCC CO2 budget δ13C isotope fractionation
2010/2/21
By comparing the global carbon cycle of the IPCC assessment reports in 1990, 1996, 2001 and 2007, it was found that despite the estimated sizes of the main carbon reservoirs and the fluxes between the...
温暖湿润区铁杉和高山松树轮δ13C的气候意义
温暖湿润区 铁杉 高山松
2009/2/13
详细了解多树种树轮碳同位素组成(δ13C)对气候的响应机制是进行古气候重建的基础. 利用川西高原温暖湿润区铁杉和高山松树轮δ13C序列, 探讨了气候环境要素对两树种δ13C的控制作用及利用该指标进行气候重建的潜力. 结果表明: 铁杉和高山松树轮δ13C序列之间存在差异, 其原因可能与树种本身的生理特性有关; 当去除大气CO2浓度引起的低频影响后, 两树种年轮碳同位素分辨率(Δ13C)序列之间的相关...