Cartography: Making Sense of Our Worlds

Abstract

One goal of cartographic research is to improve the usefulness of maps. To do so, we must consider the process of spatial knowledge acquisition, the role of maps in that process, and the content of cognitive representations derived. Research from psychology, geography, and other disciplines related to these issues is reviewed. This review is used to suggest potential new directions for research with particular attention to spatial problem solving and geographic instruction. A classroom experiment related to these issues is then described. The experiment highlights some of the implications that a concern for the process of spatial knowledge acquisition will have on questions and methods of cartographic research as well as on the use of maps in geographic instruction. It also provides evidence of independent but interrelated verbal and spatial components of regional images that can be altered by directed map work.     

The impact of climate change on U. K. river flows: A preliminary comparison of two generations of probabilistic climate projections

The impacts of climate change on future river flows are a growing concern. Typically, impacts are simulated by driving hydrological models with climate model ensemble data. The U.K. Climate Projections 2009 (UKCP09) provided probabilistic projections, enabling a risk-based approach to decision-making under climate change. Recently, an update was released—UKCP18—so there is a need for information on how impacts may differ. The probabilistic projections from UKCP18 and UKCP09 are here applied using the change factor method with catchment-based hydrological modelling for 10 catchments across England. Projections of changes in median, mean, high, and low flows are made for the 2050s, using the A1B emissions scenario from UKCP09 and UKCP18 as well as the RCP4.5 and RCP8.5 emissions scenarios from UCKP18. The results show that, in all catchments for all flow measures, the central estimate of change under UKCP18 is similar to that from UKCP09 (A1B emissions). However, the probabilistic uncertainty ranges from UKCP18 are, in all cases, greater than from UKCP09, despite UKCP18 having a smaller ensemble size than UKCP09. Although there are differences between the central estimates of change using UKCP18 RCP4.5, RCP8.5 and A1B emissions, there is considerable overlap in the uncertainty ranges. The results suggest that existing assessments of hydrological impacts remain relevant, though it will be necessary to evaluate sensitive decisions using the latest projections. The analysis will aid development of advice to users of current guidance based on UKCP09 and help make decisions about the prioritization of further hydrological impacts work using UKCP18, which should also apply other products from UKCP18 like the 12-km regional data.     

全球热浪人口暴露度预估——基于热应力指数

气候变化导致全球热浪灾害事件频发。湿球黑球温度综合考虑了温度和湿度协同作用,相较于单独的温度指标更能表征热浪对人类社会的影响。基于该指数定义热浪,利用CMIP5多模式温度和相对湿度模拟数据以及SSP3人口数据,量化并分析了未来全球及区域尺度热浪的人口暴露度变化以及造成暴露度变化的各因素的贡献率。结果表明：(1)过去(1986—2005年)暴露度的分布主要受人口分布的影响,印度次大陆以及中国东部、东南沿海地区是暴露度高值区,未来(2081—2100年)热带地区暴露度的增加尤为明显;(2)全球区域间暴露度变化差异显著,未来南亚地区平均暴露度的增幅最大,接近3×10⁴万人·d,而澳大利亚北部、亚洲北部、加拿大地区平均暴露度的增幅不足100万人·d;(3)气候和人口因素共同作用是造成绝大多数热带地区暴露度变化的最主要原因,而对于中高纬度地区来说,气候要素的贡献率最大;(4)气候和人口因素共同作用对全球暴露度变化的贡献占据主导地位。     

未来20年中国气温变化预估

利用大约40余个气候模式和模式集合,考虑多种人类排放情景,预估到2025年前相对于1961－1990年中国的气温变化。只考虑未来人类排放增加多模式集成预估结果表明,中国年平均气温自2006到2025年的20 a期间将继续变暖0.55 ℃,至2010年年平均气温平均变暖大约为1.08 ℃（平均变暖范围为 0.73-1.54 ℃）,至2020年年平均变暖约为1.43 ℃（平均变暖范围为1.10-2.09 ℃）,至2025年平均变暖约为1.39 ℃（平均变暖范围为0.94-2.19 ℃）。 对1990－2005年已经出现观测事实的近16 a气候模式预估结果进行检验表明,多模式考虑多种排放情景集成,一致预估出这16 a的明显变暖趋势,但是变暖幅度略低于实际观测值。经检测证实,对2006－2025年中国气温的预估具有一定的可信度。需要指出的是,目前的预估没有考虑未来的自然变化,只考虑人类排放继续增加的影响。     

Impact ejecta and carbonate sequence in the eastern sector of the Chicxulub crater

The Chicxulub 200 km diameter crater located in the Yucatan platform of the Gulf of Mexico formed 65 Myr ago and has since been covered by Tertiary post-impact carbonates. The sediment cover and absence of significant volcanic and tectonic activity in the carbonate platform have protected the crater from erosion and deformation, making Chicxulub the only large multi-ring crater in which ejecta is well preserved. Ejecta deposits have been studied by drilling/coring in the southern crater sector and at outcrops in Belize, Quintana Roo and Campeche; little information is available from other sectors. Here, we report on the drilling/coring of a section of 34 m of carbonate breccias at 250 m depth in the Valladolid area (120 km away from crater center), which are interpreted as Chicxulub proximal ejecta deposits. The Valladolid breccias correlate with the carbonate breccias cored in the Peto and Tekax boreholes to the south and at similar radial distance. This constitutes the first report of breccias in the eastern sector close to the crater rim. Thickness of the Valladolid breccias is less than that at the other sites, which may indicate erosion of the ejecta deposits before reestablishment of carbonate deposition. The region east of the crater rim appears different from regions to the south and west, characterized by high density and scattered distribution of sinkholes.