Accounting for risk in valuing forest carbon offsets

Background  

Forests can sequester carbon dioxide, thereby reducing atmospheric concentrations and slowing global warming. In the U.S., forest carbon stocks have increased as a result of regrowth following land abandonment and in-growth due to fire suppression, and they currently sequester approximately 10% of annual US emissions. This ecosystem service is recognized in greenhouse gas protocols and cap-and-trade mechanisms, yet forest carbon is valued equally regardless of forest type, an approach that fails to account for risk of carbon loss from disturbance.     

Regaining momentum for international climate policy beyond Copenhagen

The 'Copenhagen Accord' fails to deliver the political framework for a fair, ambitious and legally-binding international climate agreement beyond 2012. The current climate policy regime dynamics are insufficient to reflect the realities of topical complexity, actor coalitions, as well as financial, legal and institutional challenges in the light of extreme time constraints to avoid 'dangerous' climate change of more than 2°C. In this paper we analyze these stumbling blocks for international climate policy and discuss alternatives in order to regain momentum for future negotiations.     

Targeting deforestation rates in climate change policy: a "Preservation Pathway" approach

We present a new methodological approach to incorporating deforestation within the international climate change negotiating regime. The approach, called "Preservation Pathway" combines the desire for forest preservation with the need to reduce emissions associated with forest loss by focusing on the relative rate of change of forest cover as the criteria by which countries gain access to trading preserved forest carbon stocks. This approach avoids the technically challenging task of quantifying historical or future deforestation emission baselines. Rather, it places emphasis on improving quantification of contemporary stocks and the relative decline in deforestation rates necessary to preserve those stocks. This approach places emphasis on the complete emissions trajectory necessary to attain an agreed-upon preserved forest and as such, meets both forest conservation and climate goals simultaneously.     

气候变化与国家安全风险分析关键技术探索

如何量化与认知气候变化对国家安全产生的巨大风险已经成为国内外首脑高峰会议的热点之一。IPCC的报告综合了千余名科学家与专家对气候变化包括气象灾害、粮食安全、生态系统、水资源等多个领域在内的风险评估的整理、分类和分析,但大多尚处于单项领域的研究,亟须进行系统的建模和全面的风险分析。该文提出了CyberGIS模型方法,探讨对国家安全风险问题的参数化建模和形式化表达。     

Management Impacts on Forest Floor and Soil Organic Carbon in Northern Temperate Forests of the US

Background  

The role of forests in the global carbon cycle has been the subject of a great deal of research recently, but the impact of management practices on forest soil dynamics at the stand level has received less attention. This study used six forest management experimental sites in five northern states of the US to investigate the effects of silvicultural treatments (light thinning, heavy thinning, and clearcutting) on forest floor and soil carbon pools.     

Spatiotemporal variations in heat-related health risk in three Midwestern US cities between 1990 and 2010

Mortality from extreme heat is a leading cause of weather-related fatality, which is expected to increase in frequency with future climate scenarios. This study examines the spatiotemporal variations in heat-related health risk in three Midwestern cities in the USA between the years 1990 to 2010; cities include Chicago, Illinois, Indianapolis, IN and Dayton, OH. In order to examine these variations, we utilize the recently developed extreme heat vulnerability index (EHVI) that uses a principal components solution to vulnerability. The EHVI incorporates data from the US Decadal Census and remotely sensed variables to determine heat-related vulnerability at an intra-urban level (census block group). The results demonstrate significant spatiotemporal variations in heat health risk within the cities involved.     

L1 regularization for detecting offsets and trend change points in GNSS time series

Offset and trend change point detection are major problems for GNSS time series preprocessing. Without accurate detection of change points and offsets, signals estimated from GNSS time series are prone to be biased. To solve this problem, we introduced an extensive L1 regularization model, which can estimate piecewise trends, level shifts and seasonal signals simultaneously from raw GNSS time series. It thus can be used to detect trend change points and discontinuities successfully in GNSS time series. Furthermore, a new Python tool has been incorporated into our previous TSAnalyzer software to realize the benefits our L1 regularization model and some examples are listed to show its usage.     

Monitoring US agriculture: the US Department of Agriculture,National Agricultural Statistics Service,Cropland Data Layer Program

The National Agricultural Statistics Service (NASS) of the US Department of Agriculture (USDA) produces the Cropland Data Layer (CDL) product, which is a raster-formatted, geo-referenced, crop-specific, land cover map. CDL program inputs include medium resolution satellite imagery, USDA collected ground truth and other ancillary data, such as the National Land Cover Data set. A decision tree-supervised classification method is used to generate the freely available state-level crop cover classifications and provide crop acreage estimates based upon the CDL and NASS June Agricultural Survey ground truth to the NASS Agricultural Statistics Board. This paper provides an overview of the NASS CDL program. It describes various input data, processing procedures, classification and validation, accuracy assessment, CDL product specifications, dissemination venues and the crop acreage estimation methodology. In general, total crop mapping accuracies for the 2009 CDLs ranged from 85% to 95% for the major crop categories.     

北斗天线相位中心偏差改正对精密单点定位的影响

利用厂商模型、MGEX模型和ESA模型对BDS卫星天线相位中心偏差进行改正,结果表明,3种模型对BDS精密单点定位精度均有所提升,其中,水平方向提升1～2 cm,高程方向定位精度由1 dm提升为厘米级,ESA模型优于另外两种模型。利用GPS接收机天线相位中心偏差改正值对BDS接收机天线相位中心偏差进行改正,其精度改善情况随天线类型的不同而存在差异,水平方向精度影响为毫米级,高程方向与天线类型有关,精度影响最大可达厘米级。     

Economic, legal, and public policy issues influencing the creation, accessibility, and use of GIS databases

Rhind (1992) argued that government data policies and Intellectual Property Righr (IPR) considerations would play an increasingly large role in influencing the use of GIS. This has proved to be correct in general but the non-technical factors affecting data collection, supply, and price have become ever more complex. Indeed, one characteristic of the present situation is that it is now impossible to consider the legal, economic, and public policy issues in isolation. Consequently, this paper sets out to identify the interactions between them and the areas of conflict. It draws upon the literature of a much wider area than traditional GIS. This approach is essential because of two factors. The first is that GIS databases are presently of modest commercial value compared to some other data and hence key decisions on IPR, etc are being made outside our discipline. The second is that the nature of GIS databases is mutating rapidly through the wider use of multi-media and of the internet. It is concluded that the future is largely unpredictable in any detail since the interactions differ in different countries and at different moments in time. In many cases, however, revenue generation from sales or leasing of data or from services built upon data exploitation is likely to be a characteristic of both the public and the private sectors. Such charging has observable beneficial effects to set against the frequently claimed disadvantages, whether measured in financial, legal, or public access terms.     

全球气候数据集生成及气候变化应用研究

科技部在"十三五"期间部署的国家重点研发计划"全球变化及应对"专项资助了"全球气候数据集生成及气候变化关键过程和要素监测"研究项目。项目围绕由全球气候观测系统提出的基本气候变量,完善地空天基观测体系,生成中国首套以遥感数据为主体的涵盖大气、海洋和陆表长时间序列、高精度、高时空一致性的产品,即气候数据集,动态监测全球变化关键过程和要素。     

Drainage reversal in dharmapuri area in tamilnadu and its effects

Anomalies have been noticed in the Nagavati River and the Semmandakuppam ar drainage systems of the Dharmapuri area in the form of abrupt changes in the drainage pattern, elbow turning of tributary streams etc. On a detailed geomorphological study of the area using air photos, it has bsen observed that the anomalous situation is due to successive stages of development of the Nagavati R. at the cost of Semmandakuppam ar in the overall evolution of the landforms in the area. The Nagavati R. apppears to have originated as a very minor obsequent stream at an escarpment bank of the Cauvery R. which has been flowing in the southern part of the Dharmapuri pediplain. Owing probably to the uplift of the area and a concommittant reactivation of a regional shear, the Nagavati R has made successive headward advances into the pediplain, and in the process, has captured the upper reaches of the Semmandakuppam ar which is a tributary to the Ponnaiyar R. that drains the uplifted pediment even at present. The process of dissection and headward erosion by the Nagavati R. is still active and could possibly lead to a total capture of the Semmandakuppam ar and even the diversion of the Ponnaiyar R. head-waters into the Cauvery system. Of imminemt concern is the fast spreading badland which is developing at the head of the Nagavati R. at the expense of valuable agricultural land and a highway lying immediately west of the Dharmapuri town.     

《美国地图册》的设计与编制

介绍《美国地图册》的结构、设计和编制特点。该图册内容丰富、图文并茂、现势性强、比例尺较大,有助于读者更深地了解美国。     

美国阿拉斯加州佩布尔矿床开发受阻及给我们的启示

美国阿拉斯加州佩布尔斑岩型铜金钼矿床是一世界级超大型矿床.对其开发,有支持者也有反对者.支持者认为,矿床开发将给阿拉斯加州带来巨大经济收益,且不会对生态环境产生重大不利影响.而反对者认为,该矿床露天开发将不可避免地要对当地生态环境产生严重破坏,对三文鱼产业等造成重大灾难,因而坚决反对.目前,经过一系列激烈交锋、较量和斗争,反对者意见占上风和优势,矿床开发变得几乎不可能.     

Satellite observed reversal in trends of tropical and subtropical water availability

Understanding the spatially and temporally non-uniform water availability trends is key to assess changes of tropical and subtropical ecosystem productivity. However, their detailed spatial-temporal patterns and the relative role of local to the overall trend are not well known. This study provides a comprehensive investigation in characteristics of the time-varying water availability trend using the ensemble empirical mode decomposition (EEMD) method based on state-of-the-art satellite microwave observation derived microwave integrated drought index (MIDI) from 1998 to 2016. The results indicated an increased area with wetting trend since 1998, and the overall water availability reversed a drying tendency to a wetting trend around 2005. Also, the Northern Hemisphere became wetter and the Southern Hemisphere became dryer in 2016, demonstrating a transformation of favorable climate from the Southern Hemisphere to the Northern Hemisphere. Spatial patterns of the trend shape determined spatial distributions of the trend contributions, showing an opposite contribution between subtropics and tropics. Additionally, tropical rainforests and shrublands governed the overall trend reversely. This analysis helps to understand the non-uniform patterns of water availability trend and related ecosystem productivity over tropics and subtropics.