《联合国气候变化框架公约》适应谈判历程回顾与展望

减缓和适应是应对气候变化的互补性策略,但在《联合国气候变化框架公约》（简称《公约》）的谈判中,适应在很长一段时期都处于减缓的从属地位。《公约》20多年的适应谈判进程可划为早期缓慢发展、科学和技术讨论、适应与减缓并重、增强适应行动和全面适应行动5个阶段,呈现出由无到有、重要性不断增强的特点。这一特点反映了全球对气候变化影响和适应重要性认识的不断深入及适应气候变化挑战的不断增强。未来适应谈判将聚焦于如何通过《公约》现有机制增强行动及如何增加适应资金以满足发展中国家的适应需求。     

准噶尔盆地天山北麓水文地质条件变化特征

准噶尔盆地南缘(天山北麓)是新疆国民经济发展中心,水资源短缺是严重制约区内经济发展的主要因素,研究和剖析区内水文地质条件变化特征,对天山北麓地下水资源评价、规划、开发具较大指导意义.从区内50年来水文地质条件变化分析入手,阐述准噶尔盆地南缘因人类经济活动引起的水资源循环模式改变、地下水补给量减少及水位持续下降趋势变化特征,为今后区内地下水资源评价及开发利用提供较好依据.     

极地和青藏高原地区的气候变化及其影响

南极、北极和青藏高原素有地球三极之称,是多个国际计划研究全球变化的关键地区.南北极和青藏高原是全球气候变化的敏感地区,要了解全球气候变化,必须对南北极和青藏高原地区有所研究.在当前全球变暖的大背景下,地球三极地区的气候变化在时间和空间上都是多样的,这些变化对全球大气环流和我国的天气气候也会发生影响.加强对南极、北极和青...     

地球自转及其和地球物理现象的联系：Ⅰ日长变化

本文回顾了近十年来的研究进展，分各个时间尺度讨论了日长变化及其地球物理激发原因，并评估未来十年内地球自转运动可能的研究方向及课题。     

Change in habitat selection by Japanese macaques (Macaca fuscata) and habitat fragmentation analysis using temporal remotely sensed data in Niigata Prefecture,Japan

The aim of this study was to evaluate changes in macaque habitat selection during a 29-year period. We focused on the 1970s, when little crop damage was caused by Japanese macaques (Macaca fuscata), and the 2000s, when the damage became remarkable. Landsat/MSS from 1978 and ALOS/AVNIR-2 from 2007 were employed for land-cover mapping. For the 2007 land-cover classification, we applied an object-oriented image classification and a classification and regression tree. The Kappa coefficient of the 2007 land-cover map was 0.89. For the 1978 land-cover classification, change detection using principal component analysis and object-oriented image classification were applied to reduce resolution difference errors. The Kappa coefficient of the 1978 land-cover map was 0.84. We applied a Random Forest model for machine learning and data mining to predict the habitat selection of macaques. Several important environmental factors were identified for macaque habitat selection: the ratio of coniferous forest to farmland, distance to farmland, and maximum snow depth. The Random Forest model was extrapolated to the 1978 land-cover map. Over the 29-year period, coniferous forest changed to broad-leaved forest and/or mixed forest within the macaque habitat area. Coniferous forests were not selected as food resources by Japanese macaques. Furthermore, large-scale patches of farmland were used as food resources over the 29-year period. These changes indicated that habitat selection by Japanese macaques changed over the study period. The results show that the home range of macaques expanded, and macaques may now be distributed over a wider area as a result of changes in landscape configuration. Thus, forest planning, such as sustainable management of artificial conifer forests, is important for reducing crop damage.     

Change detection method based on fractal model and wavelet transform for multitemporal SAR images

The interaction is quite complex between a ground object and an electromagnetic wave transmitted by synthetic aperture radar (SAR). In a ground resolution cell illuminated by a radar beam, there are many chaotic scatterers and the whole scattering echo has the chaotic characteristics which is usually described with the fractal theory, and the fractal dimension can be used to detect the change information for multitemporal SAR images. In order to improve the change detection effect with fractal model, this paper proposes a new multitemporal SAR image change detection algorithm based on the fractal model and wavelet transform (called FMWT algorithm). The FMWT algorithm has two advantages. One is insensitive to speckle noise; the other is that the change detection accuracy is improved, comparing with a general fractal change detection (GFCD) algorithm. Since the FMWT algorithm adopts the two-dimensional discrete stationary wavelet transform (TDDSWT) technique, it can obtain different direction sub-images and avoid down-sampling of the discrete wavelet transform (DWT). In the paper, not only the simulative data test has been carried out, but also the real natural disaster SAR images have been checked. Experimental results verify that the FMWT algorithm is feasible for multitemporal SAR image change detection, it is not sensitive to speckle noise of SAR images, and the performance of it is better than that of the GFCD algorithm. At the same time, the size of a sliding window will bring some affection in counting fractal dimensions.     

Some discussions on Arctic vortex

The Arctic vortex is a persistent large-scale cyclonic circulation in the middle and upper troposphere and the stratosphere. Its activity and variation control the semi-permanent active centers of Pan-Arctic and the short-time cyclone activity in the subarctic areas. Its strength variation, which directly relates to the atmosphere, ocean, sea ice and ecosystem of the Arctic, can affect the lower atmospheric circulation, the weather of subarctic area and even the weather of middle latitude areas. The 2003 Chinese Second Arctic Research Expedition experienced the transition of the stratosphereic circulation from a warm anticyclone to a cold cyclone during the ending period of Arctic summertime, a typical establishing process of the polar vortex circulation. The impact of the polar vortex： variation on the low-level circulation has been investigated by some scientists through studying the coupling mechanisms of the stratosphere and troposphere. The impact of the Stratospheric Sudden Warming （SFW） events on the polar vortex variation was drawing people＇s great attention in the fifties of the last century. The Arctic Oscillation （ AO）, relating to the variation of the Arctic vortex, has been used to study the impact of the Arctic vortex on climate change. The recent Arctic vortex studies are simply reviewed and some discussions on the Arctic vertex are given in the paper. Some different views and questions are also discussed.     

Detecting pruning of individual stems using Airborne Laser Scanning data captured from an Unmanned Aerial Vehicle

Modern forest management involves implementing optimal pruning regimes. These regimes aim to achieve the highest quality timber in the shortest possible rotation period. Although a valuable addition to forest management activities, tracking the application of these treatments in the field to ensure best practice management is not economically viable. This paper describes the use of Airborne Laser Scanner (ALS) data to track the rate of pruning in a Eucalyptus globulus stand. Data is obtained from an Unmanned Aerial Vehicle (UAV) and we describe automated processing routines that provide a cost-effective alternative to field sampling. We manually prune a 500 m² plot to 2.5 m above the ground at rates of between 160 and 660 stems/ha. Utilising the high density ALS data, we first derived crown base height (CBH) with an RMSE of 0.60 m at each stage of pruning. Variability in the measurement of CBH resulted in both false positive (mean rate of 11%) and false negative detection (3.5%), however, detected rates of pruning of between 96% and 125% of the actual rate of pruning were achieved. The successful automated detection of pruning within this study highlights the suitability of UAV laser scanning as a cost-effective tool for monitoring forest management activities.     

Towards 3D lidar point cloud registration improvement using optimal neighborhood knowledge

Automatic 3D point cloud registration is a main issue in computer vision and remote sensing. One of the most commonly adopted solution is the well-known Iterative Closest Point (ICP) algorithm. This standard approach performs a fine registration of two overlapping point clouds by iteratively estimating the transformation parameters, assuming good a priori alignment is provided. A large body of literature has proposed many variations in order to improve each step of the process (namely selecting, matching, rejecting, weighting and minimizing). The aim of this paper is to demonstrate how the knowledge of the shape that best fits the local geometry of each 3D point neighborhood can improve the speed and the accuracy of each of these steps. First we present the geometrical features that form the basis of this work. These low-level attributes indeed describe the neighborhood shape around each 3D point. They allow to retrieve the optimal size to analyze the neighborhoods at various scales as well as the privileged local dimension (linear, planar, or volumetric). Several variations of each step of the ICP process are then proposed and analyzed by introducing these features. Such variants are compared on real datasets with the original algorithm in order to retrieve the most efficient algorithm for the whole process. Therefore, the method is successfully applied to various 3D lidar point clouds from airborne, terrestrial, and mobile mapping systems. Improvement for two ICP steps has been noted, and we conclude that our features may not be relevant for very dissimilar object samplings.     

土地利用动态遥感监测在年度土地变更调查中的应用

通过阐述土地利用动态遥感监测与年度土地变更调查的工作机制、方法和它们之间的关系,结合本人工作经验,分析利用土地利用动态遥感监测成果进行年度土地变更调查工作的现状,提出存在的问题,最后提出解决相关问题的建议。