A Practical Method for Retrieving Land Surface Temperature From AMSR-E Over the Amazon Forest

地表温度反演的单通道⽅法辩异利⽤遥感数据反演地表温度（LST）的物理基础是基于普朗克定律（Planck）量化所构成的热辐射传输⽅程。

根据卫星传感器光谱分辨率设置，反演⽅法分为单波段算法、双波段法（劈窗算法）和多波段算法。

graph TB A[LST反演] -->B(单波段算法) A --> C[双波段算法也称劈窗算法] A --> D(多波段算法) B --> E[辐射传输⽅程] B --> F[单通道算法] B --> G[单窗算法]对于但波段算法中常⽤的辐射传输⽅程法、单通道算法、单窗算法，通过查阅资料他们的主要区别如下。

1、辐射传输⽅程的⼤⽓校正法基本原理是：⾸先估计⼤⽓对地表热辐射的影响, 然后把这部分⼤⽓影响从卫星⾼度上传感器所观测到的热辐射总量中减去, 从⽽得到地表热辐射强度, 再把这⼀热辐射强度转化为相应的地表温度。

2、单通道算法单通道算法（Single-Channel Method, SC）是Jimenez-Munoz和Sobrino在对Planck函数在某个温度值附近作⼀阶Taylor级数展开⽽得出的⼀种普适性单通道算法，该算法可以针对任何⼀种热红外数据反演地表温度。

Jimenez-Munoz, JC & Sobrino, JA. A generalized single-channel method for retrieving land surface temperature from remote sensing data[J]. JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES, 108(D22):46883、单窗算法单窗算法(Mono-window Algorithm)是覃志豪等根据地表热辐射传导⽅程, 推导出的适⽤于从⼀个热波段遥感数据中推演地表温度的算法，是覃志豪等使⽤中值定理，根据热辐射传输⽅程对Planck函数进⾏线性化⼀阶Taylor级数展开，通过简化⼤⽓向上辐射亮度和⼤⽓向下辐射亮度的计算模型。

Water is an essential resource for life on Earth,and its conservation is crucial for the sustainability of our planet.Here are some practical tips and ideas that can be included in an essay on how to save water:1.Turn Off the Tap:When brushing your teeth or shaving,make sure to turn off the tap while not in use.This simple act can save gallons of water each day.2.Shorter Showers:Opt for shorter showers instead of baths,which can use up to70 gallons of ing a timer can help you keep track of the time spent in the shower.3.Install WaterSaving Appliances:Choose appliances like washing machines and dishwashers that have a high water efficiency rating.These appliances use less water per cycle.4.Fix Leaks:A dripping faucet or a leaky pipe can waste a significant amount of water over time.Regularly check for leaks and fix them promptly.e a Rain Barrel:Collect rainwater in a barrel to use for watering plants or washing cars.This not only saves water but also reduces runoff that can pollute local waterways.6.Water Plants Wisely:Water your garden early in the morning or late in the evening to minimize e a drip irrigation system or soaker hoses to deliver water directly to the roots of plants.7.Mulch Your Garden:Mulching helps to retain soil moisture,reducing the need for frequent watering.It also suppresses weed growth,which competes with plants for water.8.Reuse Water:Reuse water from cooking or cleaning vegetables for watering plants or flushing toilets.This can significantly reduce your water consumption.cate Others:Spread awareness about the importance of water conservation. Encourage friends,family,and neighbors to adopt watersaving practices.10.Support Water Conservation Policies:Advocate for and support policies that promote water conservation and sustainable water use in your community.11.Be Mindful of Water Use:Always be conscious of your water use.Small changes in daily habits can lead to significant water savings over time.12.Invest in WaterSaving Fixtures:Replace old faucets and showerheads with lowflowmodels.These fixtures can reduce water flow without compromising performance.By incorporating these tips into your daily routine,you can contribute to the global effort to conserve water and ensure that this precious resource is available for future generations.Remember,every drop counts!。

高二英语科研项目实施单选题40题(带答案)1.In the scientific research project, we need to collect data _____.A.accuratelyB.exactlyC.preciselyD.correctly答案：A。

“accurately”强调准确地，在科研项目中收集数据需要准确无误。

“exactly”表示确切地、完全地；“precisely”精确地，和“accurately”意思较为接近但在科研收集数据的场景下，“accurately”更常用；“correctly”正确地，通常用于方法等正确，不太符合收集数据的语境。

2.When presenting the research results, we should express our ideas _____.A.clearlyB.obviouslyC.apparentlyD.visibly答案：A。

“clearly”清晰地，在展示研究结果时要表达清晰。

“obviously”明显地；“apparently”显然地；“visibly”看得见地，后三个选项不太符合表达想法的语境。

3.The scientific research project requires ______ teamwork.A.cohesiveB.unitedC.cooperativeD.joined答案：C。

“cooperative”合作的，科研项目需要合作的团队合作。

“cohesive”有结合力的；“united”联合的；“joined”连接的，这三个选项不太符合团队合作的语境。

4.We must analyze the data ______ to draw accurate conclusions.A.thoroughlypletelyC.entirelyD.wholely答案：A。

“thoroughly”彻底地，分析数据需要彻底才能得出准确结论。

Persistence is a quality that is often celebrated in various walks of life.It is the ability to continue striving for a goal despite obstacles,setbacks,and failures.Here are some key points that can be included in an essay about persistence:1.Definition of Persistence:Begin by defining what persistence means.It is the continuous effort to achieve a goal despite difficulties.2.Importance of Persistence:Discuss why persistence is important.It is a key to success in various fields such as academics,sports,business,and personal development.3.Historical Examples:Provide examples of historical figures who demonstrated persistence.Thomas Edisons numerous attempts to invent the light bulb,or Abraham Lincolns political career before becoming president,are classic examples.4.Overcoming Failure:Explain how persistence helps individuals to overcome failure.It allows them to learn from their mistakes and keep moving forward.5.Developing a Growth Mindset:Discuss the concept of a growth mindset and how it is closely linked to persistence.People with a growth mindset see challenges as opportunities to grow and improve.6.Strategies for Persistence:Offer practical strategies that individuals can use to cultivate persistence.This might include setting realistic goals,breaking down larger tasks into smaller steps,and seeking support from others.7.The Role of Motivation:Describe the role of motivation in fostering persistence. Motivation can come from intrinsic factors,such as personal satisfaction,or extrinsic factors,such as rewards or recognition.8.Coping with Setbacks:Discuss how persistence helps in coping with setbacks.It involves maintaining a positive attitude and finding ways to adapt and overcome obstacles.9.Longterm Benefits:Highlight the longterm benefits of being persistent.This can include achieving ones goals,developing resilience,and gaining the respect of others. 10.Conclusion:Conclude the essay by summarizing the importance of persistence and encouraging readers to embrace this quality in their own lives.Remember to use clear and concise language,provide specific examples,and perhaps include a personal anecdote to illustrate the power of persistence.。

H unting and the Setting of Inner EurasiaWords & Phrases1.Inner Eurasia：内部的欧亚大陆Eurasia=Europe+Asia2.refer to：指的是3.systematic colonization of parts of Inner Eurasia：内部欧亚大陆部分地区的系统性的人类移民定居colonization：指移民定居=settlement4.The long, cold, arid winters of this region’s steppes (grass covered plains)posed two distinctive problems for human settlers.Arid：adj. 干旱的Semiarid：adj. 半干旱的Posed two distinctive problems: 构成两个不同的难题Pose：v. 提出，造成(威胁、问题)=presentDistinctive：adj. 与众不同的，独特的5.Presumably their ability to scavenge animal carcasses meant that they coulduse skins or furs for warmth.Presumably：adv. 据推测地Presume=assume：v. 推测Scavenge：捡破烂;拾荒;(从废弃物中)觅食，寻找 If people or animals scavenge for things, they collect them by searching among waste or unwanted objects.Carcass: n. 动物的尸体残骸A carcass is the body of a dead animal6.However, there are no signs of hearths before about 200,000 years ago.Hearth：n. 灶台，火炉7.This suggests that humans used fire opportunistically and had not yetdomesticated it enough to survive the harsh winters of Ice Age Inner Eurasia.Domesticate：v. 驯养，驯服Dome：n. 圆屋顶区别：dominate：v. 统治，主导Harsh winters：严酷的冬天8.trickier problem：棘手的问题，难以解决的问题9.Humans could not exploit the abundant grasses of the steppes, and most ofthe edible plants died off in winter.Exploit：v. 开发利用=utilize=make use ofSteppe: 干草原The edible plants: 可食的植物10.Animals, unlike plants, can evade predators and may even fight back.Evade predators：躲避捕猎者衍生：inevitable：adj. 不可躲避的，不可避免的=unavoidable11.hunting gear: 打猎装备12.the choice of companions：伙伴的选择13.the maintenance of communications with neighbors：与邻居交流联系的维持14.fatal：adj. 致命的=deadly15.clarify group identity：表明群体身份16.Internally, groups may split for long periods as hunting parties travelling overgreat distances.Internally：adv. 从内在来看Split：v. 分裂17.All in all, each group has to exist and survive in several distinct configurations.Configuration：n.安排;格局;布局 A configuration is an arrangement of a group of thingsSyntax1.According to the formulation of archaeologist Lewis Binford, in atypical hunter/collector food-gatheringleave camps with very specific goals inknowledge of their intended prey.Formulation：n.(政策、计划等的)制定，构想 The formulation of something such as a policy or plan is the process of creating or inventing it.Intimate: adj.深刻的;详尽的;精通的 An intimate knowledge of something is a deep and detailed knowledge of it2.They may by away for days or weeks at a time and will often storetheir kill at specific storage sites, from which they will bring food back to a base camp when needed.3.As a result, they move their base camps less often than in foragersocieties, but they range more widely, their movements are more carefully planned, and so are their methods of storage.Base camp: 基地，相对于summer camp等季节性营地Forager：n. 搜寻草料觅食者Range：v. 搜索，延伸4.They need reliable information about the movements and habits ofanimal prey over large areas, which can be secured only by maintaining regular contacts with neighboring groups.5.Finally, they need reliable methods of storage because, where plantfoods cannot provide a dietary safety net, planning has to be precise and detailed to ensure that there is enough to tide them over in periods of shortage.Precise：adj. 精准的=exactTide over: 渡过难关tide: n. 海浪；v. 顺应潮水航行6.The regular exchange of information and sometimes of materialgoods is critical not only within groups, but also between groups scattered over large distances.Critical：adj. 重要的7.For these reasons, archaeologist Clive Gamble has argued that thedifficulties of settling the Eurasian heartland arose less from thethe social and organizational features ofHuman community=human society 人类社会8.Nor is there any physical evidence for storage, raw materials allcome from within a radius of 50 kilometers—and usually less than 5 kilometers—of the sites where they were used.physical evidence：有形的证据=concrete evidenceraw materials：原材料Abstract →Concrete1.The long, cold, arid winters of this region’s steppes (grass coveredplains) poised two distinctive problems for human settlers.2.Systematic and reliable hunting methodsstructures.3.Hunting strategies also imply greater social complexity.Written RecordsWords & Phrases1.appropriate texts: 恰当的文本记录appropriate：adj. Something that is appropriate is suitable or acceptable for a particular situation.2.Many of the early excavations of the great sites of the Near Easthad the recovery of clay writing tablets as the main goal.Excavation: n. 挖掘=unearthingRecovery：n. 收回；取回；失而复得 You talk about the recovery of something when you get it back after it has been lost or stolen clay writing tablets: 粘土写字板3.it is mainly official decrees inscribed on marble that have survivedofficial decrees inscribed on marble: 刻在大理石上的官方法令decree：n. A decree is an official order or decision, especially one made by the ruler of a countryinscribe: v. 刻;雕 If you inscribe words on an object, you write or carve the words on the objectmarble: n. 大理石4.We can now also begin to deduce the likely territories belonging toindividual Maya centers.Deduce：v. 推断Territory：n. 领土5.But one should not accept them uncritically at face value.Uncritically：adv. 不加批评地，不加鉴别地区别于：critical：最常见的意思是“重要的”，也有“批判的”意思crucial：只有“重要的”意思at face value: 按照表面意思;(对…)信以为真 If you take something at face value, you accept it and believe it without thinking about it very much, even though it might be untrue6.historians tend to think of a king as the leader of a state societytend to: 倾向于think of…as: 把…看作为= see …as = view…as= regard…asstate society: 国家社会，区别于以往未形成国家的社会7. a full state society did not emergeemerge：v. 出现emergence：n. 出现emergency：n. 紧急事件的出现，急诊反义词：immerse：v. 浸没，陷入Syntax：1.Major finds of this kind are still being made—for example, at theancient city of Ebla (Tell Mardikh) in Syria, where an archive of 5,000 clay tablets written in an early dialect of Akkadian (Babylonian) was discovered in the 1970s.Archive: n. 档案;史料;记录;档案馆 The archive or archives are a collection of documents and records that contain historical information. You can also use archives to refer to the place wherearchives are storedDialect：n. 方言Babylonian：n. 巴比伦人（了解即可）2.For instance, the clay tablets of Mycenaean Greece, dating fromaround all, without exception, primarily records of commercial (goods coming in or going out) at the (插入语割裂，逗号前后要连起来读)Transaction：n. (一笔)交易;业务 A transaction is a piece of business, for example an act of buying or selling something8.This discovery gives us many aspects of theMycenaean economy craft organization (through the names for the different kinds of craftspeople, as well as introducing the names of the offices of state).（并列对象的确定）Aspect：n. 方面spect：词根，看的意思，a + spect=八面玲珑中的一面，方面prospect：向前看，所以是“n.前景，前途，预期”的意思inspect：向里看，所以是“v.检查”的意思retrospect：向回看，所以是“n./v. 回顾回想”的意思a glimpse into：一瞥，看一眼glimpse：n./v. 一瞥，一看craft organization: 工艺组织craft：n.手艺;工艺 A craft is an activity such as weaving, carving, or pottery that involves making things skilfully with your handscraftman=artisan 手工艺人，工匠9.It could be that the Mycenaeans wrote on clay only for theircommercial records and used other perishable materials for literary or historical texts now lost to us.（记住介词的基本意思，to = toward表朝向）Lost to us：朝向我们来说是失去的，即我们无法得到指前面的historical texts现在lost to usPerishable：adj. 易腐烂的；易腐败的；易毁灭的10.Fragile rolls of papyrus—the predecessor of modern paper—withliterary texts on them, have usually remained intact only when retained in the dry air of Egypt, or when buried beneath the volcanic ash covering Pompeii（记住介词的基本意思，with 表伴随）Fragile rolls of papyrus：脆弱的莎草纸卷轴Predecessor：n. 前身remained intact：仍然完好无损intact：adj. 完整无缺的，未受破坏的 Something that is intact is complete and has not been damaged or changed 考过词汇题=wholeretained in the dry air：被保留在干燥空气中retain：v. 保留buried beneath the volcanic ash：被埋在火山灰下11.Coins also provide a valuable source of written records: they canreveal information about the location where they are found, which can provide evidence about trade practices there, and their inscriptions can be informative about the issuing authority, whether they were city-states (as in ancient Greece) or sole rulers (as in Imperial Rome or in the kingdoms of medieval Europe).（1）逗号之后的which，修饰指代对象的确定，此时的which可以指代前面整句话（2）and并列对象/级别的确定trade practices：贸易行为inscriptions：n. 碑文，题刻informative：adj. 提供信息的issuing authority：发行当局city-states：城邦国家（多个城市联邦国家）sole rulers：单一统治者medieval Europe：中世纪的欧洲12.It had been widely assumed that the inscriptions were exclusively ofa calendrical nature or that they dealt with purely religious matters,notably the deeds of the gods.Be+prep.Or that并列对象的确定：与前面的that并列widely assumed：被广泛推测认为exclusively of a calendrical nature：只属于一种历法的属性/性质deal with：处理，涉及deal的过去式是dealtnotably：adv. 尤其地，显著地deeds of the gods：神的行为13.Therefore, when the earliest records for Anglo-Saxon England, foundin the Anglo-Saxon Chronicle, which took final shape in about A.D.以逗号隔开引入的插入语Which修饰对象的确定看到谓语想主语，主语在很遥远的前方Took final shape: 最终成型Refer to：提及，指的是Abstract →Concrete1.Paragraph 2 In each early literate society, writing had its ownfunction and purpose.段首主题句中的抽象概念往后找具体对应Literate society：识字社会，有读写能力的社会2.But here, as in other cases, accidents of preservation may beimportant.3.Maya history has thus taken on a new dimension.段尾总结句中的抽象概念往前找对应Take on a new dimension: 呈现出一个新的维度Take on：呈现Dimension：n. 维度，角度，方面 A particular dimension of something is a particular aspect of it3D= 3 dimension 三维3-dimension film ：3D电影4.Nor should one forget the bias introduced by the accidents ofpreservation and the particular uses of literacy in a society.理解标黄单词抽象意义的具体指代Bias：n. 偏见，误解Literacy：n. 文字5.The great risk with historical records is that they can impose theirown perspective so that they begin not only to supply the answers to our questions but subtly to determine the nature of those questions and even our concepts and terminology.理解标黄单词抽象意义的具体指代Impose their own perspective：施加他们自己的观点Perspective：n. 看问题的角度，观点So that：conj. 结果Subtly：adv. 微妙地The nature of those questions: 问题得性质Concept：n. 概念，理解=understanding，ideaTerminology：n. 专门术语，概念来自term概念的意思Temperature Regulation in Marine OrganismsWords & Phrases1.Most birds have a body temperature of about 40℃, whereas thetemperature of most marine mammals is about 38℃.Whereas：conj. 表比较=while2.All subtidal marine invertebrates and most fishes fit into thiscategory.Subtidal marine invertebrates：下潮区的海洋无脊椎动物衍生：intertidal：adj. 潮间区的，即处在涨潮海水覆盖和落潮陆地暴露之间的区域；而subtidal永远处在潮下面的区域，来自词根sub，下面的意思，如subwayVertebrate：脊椎动物Fit into: 适合3.Their rise in temperature above ambient conditions stems frommetabolic heat generated by muscular activity (swimming) combined with a heat retention mechanism.Ambient condition：周边的状况Stem from：来自=arise from=come fromMetabolic heat：新陈代谢的热量Metabolism：n. 新陈代谢Combine with：与…结合A heat retention mechanism: 一个热量保留机制Retention：n. 保留 The retention of something is the keeping of it Retain：v. 保留反义词：drain：v. 流失Brain drain：人才流失，智囊流失Mechanism：n. 原理，机制；方法4.sustained activity：持续进行的活动sustained=continueding both evaporation and circulation of body fluids to avoid beingheated at low tide by the Sunevaporation and circulation of body fluids：体液的蒸发和循环evaporation：n. 蒸发vapor：n. 水蒸气区别：transpiration：n. (植物的)蒸腾作用Body fluids：体液6.absorb and lose heat directly to the air：直接朝向空气吸热和失热absorb：v. 吸收to=toward，表朝向7.variation in color can reflect differences in adaptation to thecapture of solar energy at different latitudesvariation in color：色彩差异reflect：v. 反映；反射adaptation to：朝向…的适应性capture of solar energy：太阳能量的捕获latitudes：n. 纬度区别：longitude：经度altitude：海拔高度8.direct conduct of heat from the skin to the contacting colder waterdirect conduct of heat：热的直接传导conduct：n. 传导；行为举止contacting colder water：接触的冷水9.circulatory system：循环系统10.heat loss from the body surface also occurs as warm interior blood istransferred and moves into contact with the periphery of the body warm interior blood：温暖的内部血液interior：adj. 内部的exterior：adj. 外部的transferred：v.转移，转学区别：transform：v. 变形，转变；transport：v. 运输contact：n. 接触periphery: 边缘；周围；外围 If something is on the periphery of an area, place, or thing, it is on the edge of it11.Their bodies also radiate heat, usually in the infrared part of thespectrum.radiate heat: 辐射热量infrared：n. 远红外线spectrum：n. 谱线，光谱12.as animals exhale, the resulting evaporation of water involves aconsiderable loss of heatexhale：v. 出气，呼出气反义：inhale：v. 吸气Considerable：adj. 极大量的=substantial=significant=a large number of13.A series of interlocking contour feathers encloses a thick layer ofdown feathers that traps stationary air, which in turn acts as an insulating layer.interlocking contour feathers：相互交联的轮廓线羽毛contour: n. 轮廓;外形 You can refer to the general shape or outline of an object as itscontoursenclose: v. 包围;围住;封闭 If a place or object is enclosed bysomething, the place or object is inside that thing or completely surrounded by itdown feathers: 绒毛，down jacket：羽绒服stationary：adj. 静止不动的=motionless=stillin turn：反过来acts as：起…作用，扮演…insulating layer: 隔热层14.subcutaneous fat：皮下脂肪subcutaneous：adj. 皮下的（了解即可）15.constantly preen and fluff up a relatively thick layer of furpreen：v. 用嘴整理羽毛When birds preen their feathers, they clean them and arrange them neatly using their beaksfluff up：打松，使变得松软fluff：n. 绒毛，软毛；v. 使变松relatively：adv. 相对地，相比较而言地=comparatively16.terrestrial (land) animals：陆地动物terrestrial：adj. 陆地的---反义aquatic：水生的terrestrial：adj. 地球的—反义extraterrestrial：地外的，eg. extraterrestrial life: 地外生命17.the limbs are the principal sources of heat losslimb：n. 四肢18.warm arterial blood must be supplied to limbsarterial blood：动脉血arterial：adj. 动脉的artery：n. 动脉，也可引申为交通/贸易大动脉eg. trade arteryvein：n. 静脉19.Heat loss in porpoises is minimized by a countercurrent heatexchangerPorpoise: n. 小海豚（了解即可）Minimize：v. 最小化----反义maximize：v. 最大化Minimum：n. 最小值；maximum：n. 最大值countercurrent heat exchanger：对流热交换器countercurrent：n. 逆流，对流counter：v. 对抗= resist（考过词汇题）counterargument：n. 对立观点counterexample：n. 反面例子20.This spatial relationship of circulatory vessels minimizes heat loss tothe flipper and thence to the water.spatial relationship：空间关系spatial来自spacecirculatory vessels：循环血管vessel：n. 有很多意思，此处是血管的意思，还有“器皿，船只”的意思，都是承载物flipper：n. 脚蹼thence=then 然后21.anatomical details：解剖细节anatomical: adj. 解剖的anatomy：n. 解剖，本质上指的是内部的身体构造，要理解到这个层面上来，例如下句：fishes have a circulatory anatomy based on the same overall design overall：adj. 整体的=general22.Arteries and veins in the near-surface musculature are in contact,and in arteries and veins, respectively, blood flows in opposite directionsMusculature：n. 肌肉组织（了解即可），来自muscle肌肉，这个必须知道in contact：处在接触中respectively：adv. 分别地，各自地=separately（考过词汇题）opposite directions：相反的方向opposite：adj. 相反的oppose：v. 反对opponent：n. 反对者—反义词，支持者：proponent，advocate，supporter，这些都得记下来，很常见Syntax：1.Homeotherms are organisms that regulate body temperature to aconstant level, usually above that of the ambient (surrounding) environment.比较关系中重复概念用that替代，读者须知that的替代对象，本句中that=temperatureHomeotherms：n. 恒温动物（了解即可）therm：词根，热的意思，eg. geothermal：地热的constant：adj. 稳定不变的= steady2.Poikilotherms are organisms whose body temperature conforms tothat of the ambient environment.比较关系中重复概念被that替代Poikilotherms：n. 变温动物（了解即可）Conform to：符合，遵从 If someone or something conforms to a pattern or type, they are very similar to itAmbient：adj. 周围的，周边的3.There is an interesting intermediate status in which bodytemperature is usually somewhat higher than ambient temperature.介词+which，which指介词前面的名词，对该名词做修饰展开intermediate status：居间状态intermediate：adj. 居间的，中间的ambient temperature：周边的温度4.The arteries are surrounded by veins, within which blood is returningto the core of the animal.介词+which，which指介词前面的名词，对该名词做修饰展开Artery：n. 动脉Vein：n. 静脉Core：n. 中心；地核Core of the animal: 动物的身体中心Abstract →Concrete1.The first line of defense against heat loss is a well-insulated bodysurface.Well-insulated: adj. 绝缘的，隔热的。

Unit ed NationsFramework Convention on Climate Change Chaptername Xxxzz, Sample TextSecont Line Lorem Ipsum DoloreCD M Methodology Booklet Nov ember 2013 (up to EB 75)METHODOLOGIESFOR AFFORESTATIONAND REFORESTATION(A/R) CDM PROJECTACTIVITIESChapter IVCD M Methodology BookletThe following conditions and information are relevantfor all A/R methodologies and are applicable in additionto the conditions listed in the methodology summaries:• Vegetation cover on the land eligible for project activities must have been below the forest threshold7on 31 December 1989. This needs to be proven(e.g. using satellite image or participatory ruralappraisal (PRA));• No tree vegetation is expected to emergewithout human intervention to form a foreston the project land;• Project start date must be January 1, 2000 or later. • In absence of the project activity, carbon stocks of the carbon pools not considered in the project activityare expected to decrease or increase less relativeto the project scenario.A/R CDM project activities result in t-CERs and l-CERs. A/R methodologies can be distinguished as large-scale and small-scale. Small-scale A/R methodologies provide simpliied approaches for project design and monitoring. Small-scale A/R project activities must fulil the following conditions:(1) Net anthropogenic GHG removals by sinks mustbe less than 16,000 tons of CO2per year; and(2) The project activities must be developed orimplemented by low-income communities andindividuals as determined by the host Party.If an A/R CDM project activity does not meet these criteria an A/R large-scale methodology has to be applied.4.1. INTRODUCTION TOMETHODOLOGIES FOR A/RCDM PROJECT ACTIVITIES7The host country determines the forest deinition which lies within the following thresholds:A single minimum tree crown cover value between 10 and 30%; and a single minimum landarea value between 0.05 and 1 hectare; and a single minimum tree height value between2 and 5 metresA short description of methodological tools relevant to A/R methodologies can be found below.COMBINED TOOL TO IDENTIFY THE BASELINE SCENARIO AND DEMONSTRATE ADDITIONALITY IN A/R CDM PROJECT ACTIVITIESThis tool provides a step-wise approach to identifythe baseline scenario and simultaneously demonstrate additionality. These steps include:Step 0 Preliminary screening based on the starting date of the A/R project activity;Step 1 Identiication of alternative land use scenarios; Step 2 Barrier analysis;Step 3 Investment analysis (if needed);Step 4 Identiication of the baseline scenario;Step 5 Common practice analysis.This tool is not applicable to small-scale project activities.CALCULATION OF THE NUMBER OF SAMPLE PLOTS FORMEASUREMENTS WITHIN A/R CDM PROJECT ACTIVITIESThis tool can be used for calculation of number of sample plots required for estimation of biomass stocks from sampling based measurements in the baseline and project scenarios of an A/R CDM project activity.The tool calculates the number of required sample plotson the basis of the speciied targeted precision for biomass stocks to be estimated.The tool applies the following assumptions:(a) Approximate value of the area of each stratum withinthe project boundary is known;(b) Approximate value of the variance of biomass stocksin each stratum is known from a preliminary sample,existing data related to the project area, or existingdata related to a similar area;(c) The project area is stratiied into one or more strata.4.2. METHODOLOGICAL TOOLS FOR A/R CDM PROJECT ACTIVITIESESTIMATION OF NON-CO2 GHG EMISSIONS RESULTING FROM BURNING OF BIOMASS ATTRIBUTABLE TO AN A/R CDM PROJECT ACTIVITYThis tool can be used for estimation of non-CO2GHG emissions resulting from all occurrence of ire within the project boundary, i.e. burning of biomass when ireis used for site preparation and/or to clear the land of harvest residue prior to replanting of the land, orwhen a forest ire occurs within the boundary of anA/R CDM project activity.For burned areas exceeding a minimum area described in the tool, it provides separate step-by-step calculationsand parameter estimation for non-CO2GHG emissions from site preparation and from forest ires.ESTIMATION OF CARBON STOCKS AND CHANGE IN CARBON STOCKSIN DEAD WOOD AND LITTER IN A/R CDM PROJECT ACTIVITIESThis tool can be used for ex post estimation of carbon stocks and change in carbon stocks in dead woodand/or litter in the baseline and project scenarios ofan A/R CDM project activity. This tool has no internal applicability conditions.ESTIMATION OF CARBON STOCKS AND CHANGE IN CARBON STOCKSOF TREES AND SHRUBS IN A/R CDM PROJECT ACTIVITIESThis tool can be used for estimation of carbon stocksand change in carbon stocks of trees and shrubs in the baseline and project scenarios of an A/R CDM project activity. This tool has no speciic internal applicability conditions.ESTIMATION OF THE INCREASE IN GHG EMISSIONS ATTRIBUTABLETO DISPLACEMENT OF PRE-PROJECT AGRICULTURAL ACTIVITIESIN A/R CDM PROJECT ACTIVITYThis tool provides a step-by-step method for estimating increase in GHG emissions resulting from displacement of pre-project agricultural activities from the project boundary of an A/R project activity under the CDM. The tool estimates the increase in emissions on the basis of changes in carbon stocks in the affected carbon pools in the land receiving the displaced activities.TOOL FOR ESTIMATION OF CHANGE IN SOIL ORGANIC CARBON STOCKSDUE TO THE IMPLEMENTATION OF A/R CDM PROJECT ACTIVITIESThis tool estimates the change, occurring in a given year,in soil organic carbon (SOC) stocks of land within the boundary of an A/R CDM project activity. The tool is only applicable if litter remains on site during the A/R CDM project activity and soil disturbance for site preparation and project activity is limited. It is not applicable on land containing organic soils or wetlands, and if speciic land management practices with inputs are applied. Speciic management practices limitations are listed in the toolfor each temperature/moisture regime.DEMONSTRATING APPROPRIATENESS OF VOLUME EQUATIONSF OR ESTIMATION OF ABOVEGROUND TREE BIOMASS IN A/R CDMPROJECT ACTIVITIESThis tool allows demonstration whether a volume table or volume equation, in combination with selected biomass expansion factors (BEFs) and basic wood density, is appropriate for estimation of aboveground tree biomassin an A/R CDM project activity. It provides criteria for direct applicability of an equation for ex post calculations, and – if these criteria are not met – describes the process required for veriication of a volume equation. This tool has no internal applicability conditions.DEMONSTRATING APPROPRIATENESS OF ALLOMETRIC EQUATIONSFOR ESTIMATION OF ABOVEGROUND TREE BIOMASS IN A/R CDMPROJECT ACTIVITIESThis tool allows demonstration whether an allometric equation is appropriate for estimation of aboveground tree biomass in an A/R CDM project activity. It provides criteria for direct applicability of an equation for ex ante and ex post calculations, and – if these criteria are notmet – describes the process required for veriication of an allometric equation. This tool has no internal applicability conditions.DEMONSTRATION OF ELIGIBILITY OF LANDS FOR A/R CDM PROJECT ACTIVITIESThis tool provides a step-by-step method for demonstrating eligibility of land for an A/R CDM project activity. The tool also speciies the types of information and data that are required to be furnished for demonstration of eligibility of land. Aerial photographs or satellite imagery complemented by ground reference data, land-use or land-cover information from maps or digital spatial datasets, and data from ground-based surveys or existing records (e.g. permits or plans, cadaster or owner registers) are allowed to be used for demonstrating land eligibility. The tool also allows use of a written testimony resulting from participatory rural appraisal (PRA) where other form of data is either not available or is inadequate.CDM Methodology BookletChapter IV4.3. METHODOLOGIES FOR LARGE-SCALE A/R CDM PROJECT ACTIVITIESAR-AM0014 Aforestation and reforestation of degraded mangrove habitatsAR-ACM0003 Aforestation and reforestation of lands except wetlandsCDM Methodology BookletChapter IV4.4. METHODOLOGIES FOR SMALL-SCALE A/R CDM PROJECT ACTIVITIESCD M Methodology Booklet Nov ember 2013 (up to EB 75)United NationsFramework Convention on Climate ChangeAR-AMS0003AR-AMS0003 Small-scale A/R CDM project activities implemented on wetlandsCD M Methodology Booklet Nov ember 2013 (up to EB 75)United NationsFramework Convention onClimate ChangeAR-AMS0007AR-AMS0007 Small-scale A/R CDM project activities implemented on lands other than wetlands。

GGALVANIC DISTORTIONThe electrical conductivity of Earth materials affects two physical processes:electromagnetic induction which is utilized with magneto-tellurics(MT)(q.v.),and electrical conduction.If electromagnetic induction in media which are heterogeneous with respect to their elec-trical conductivity is considered,then both processes take place simul-taneously:Due to Faraday’s law,a variational electric field is induced in the Earth,and due to the conductivity of the subsoil an electric cur-rent flows as a consequence of the electric field.The current compo-nent normal to boundaries within the heterogeneous structure passes these boundaries continously according tos1E1¼s2E2where the subscripts1and2indicate the boundary values of conductiv-ity and electric field in regions1and2,respectively.Therefore the amplitude and the direction of the electric field are changed in the vicinity of the boundaries(Figure G1).In electromagnetic induction studies,the totality of these changes in comparison with the electric field distribution in homogeneous media is referred to as galvanic distortion. The electrical conductivity of Earth materials spans13orders of mag-nitude(e.g.,dry crystalline rocks can have conductivities of less than 10–6S mÀ1,while ores can have conductivities exceeding106S mÀ1). Therefore,MT has a potential for producing well constrained mod-els of the Earth’s electrical conductivity structure,but almost all field studies are affected by the phenomenon of galvanic distortion, and sophisticated techniques have been developed for dealing with it(Simpson and Bahr,2005).Electric field amplitude changes and static shiftA change in an electric field amplitude causes a frequency-indepen-dent offset in apparent resistivity curves so that they plot parallel to their true level,but are scaled by a real factor.Because this shift can be regarded as spatial undersampling or“aliasing,”the scaling factor or static shift factor cannot be determined directly from MT data recorded at a single site.If MT data are interpreted via one-dimensional modeling without correcting for static shift,the depth to a conductive body will be shifted by the square root of the factor by which the apparent resistivities are shifted.Static shift corrections may be classified into three broad groups: 1.Short period corrections relying on active near-surface measurementssuch as transient electromagnetic sounding(TEM)(e.g.,Meju,1996).2.Averaging(statistical)techniques.As an example,electromagneticarray profiling is an adaptation of the magnetotelluric technique that involves sampling lateral variations in the electric field con-tinuously,and spatial low pass filtering can be used to suppress sta-tic shift effects(Torres-Verdin and Bostick,1992).3.Long period corrections relying on assumed deep structure(e.g.,a resistivity drop at the mid-mantle transition zones)or long-periodmagnetic transfer functions(Schmucker,1973).An equivalence relationship exists between the magnetotelluric impedance Z and Schmucker’s C-response:C¼Zi om0;which can be determined from the magnetic fields alone,thereby providing an inductive scale length that is independent of the dis-torted electric field.Magnetic transfer functions can,for example, be derived from the magnetic daily variation.The appropriate method for correcting static shift often depends on the target depth,because there can be a continuum of distortion at all scales.As an example,in complex three-dimensional environments near-surface correction techniques may be inadequate if the conductiv-ity of the mantle is considered,because electrical heterogeneity in the deep crust creates additional galvanic distortion at a larger-scale, which is not resolved with near-surface measurements(e.g.,Simpson and Bahr,2005).Changes in the direction of electric fields and mixing of polarizationsIn some target areas of the MT method the conductivity distribution is two-dimensional(e.g.,in the case of electrical anisotropy(q.v.))and the induction process can be described by two decoupled polarizations of the electromagnetic field(e.g.,Simpson and Bahr,2005).Then,the changes in the direction of electric fields that are associated with galvanic distortion can result in mixing of these two polarizations. The recovery of the undistorted electromagnetic field is referred to as magnetotelluric tensor decomposition(e.g.,Bahr,1988,Groom and Bailey,1989).Current channeling and the“magnetic”distortionIn the case of extreme conductivity contrasts the electrical current can be channeled in such way that it is surrounded by a magneticvariational field that has,opposite to the assumptions made in the geo-magnetic deep sounding(q.v.)method,no phase lag with respect to the electric field.The occurrence of such magnetic fields in field data has been shown by Zhang et al.(1993)and Ritter and Banks(1998).An example of a magnetotelluric tensor decomposition that includes mag-netic distortion has been presented by Chave and Smith(1994).Karsten BahrBibliographyBahr,K.,1988.Interpretation of the magnetotelluric impedance tensor: regional induction and local telluric distortion.Journal of Geophy-sics,62:119–127.Chave,A.D.,and Smith,J.T.,1994.On electric and magnetic galvanic distortion tensor decompositions.Journal of Geophysical Research,99:4669–4682.Groom,R.W.,and Bailey,R.C.,1989.Decomposition of the magneto-telluric impedance tensor in the presence of local three-dimensional galvanic distortion.Journal of Geophysical Research,94: 1913–1925.Meju,M.A.,1996.Joint inversion of TEM and distorted MT sound-ings:some effective practical considerations.Geophysics,61: 56–65.Ritter,P.,and Banks,R.J.,1998.Separation of local and regional information in distorted GDS response functions by hypothetical event analysis.Geophysical Journal International,135:923–942. Schmucker,U.,1973.Regional induction studies:a review of methods and results.Physics of the Earth and Planetary Interiors,7: 365–378.Simpson,F.,and Bahr,K.,2005.Practical Magnetotellurics.Cam-bridge:Cambridge University Press.Torres-Verdin,C.,and Bostick,F.X.,1992.Principles of special sur-face electric field filtering in magnetotellurics:electromagnetic array profiling(EMAP).Geophysics,57:603–622.Zhang,P.,Pedersen,L.B.,Mareschal,M.,and Chouteau,M.,1993.Channelling contribution to tipper vectors:a magnetic equivalent to electrical distortion.Geophysical Journal International,113: 693–700.Cross-referencesAnisotropy,ElectricalGeomagnetic Deep SoundingMagnetotelluricsMantle,Electrical Conductivity,Mineralogy GAUSS’DETERMINATION OF ABSOLUTE INTENSITYThe concept of magnetic intensity was known as early as1600in De Magnete(see Gilbert,William).The relative intensity of the geomag-netic field in different locations could be measured with some preci-sion from the rate of oscillation of a dip needle—a method used by Humboldt,Alexander von(q.v.)in South America in1798.But it was not until Gauss became interested in a universal system of units that the idea of measuring absolute intensity,in terms of units of mass, length,and time,was considered.It is now difficult to imagine how revolutionary was the idea that something as subtle as magnetism could be measured in such mundane units.On18February1832,Gauss,Carl Friedrich(q.v.)wrote to the German astronomer Olbers:“I occupy myself now with the Earth’s magnetism,particularly with an absolute determination of its intensity.Friend Weber”(Wilhelm Weber,Professor of Physics at the University of Göttingen)“conducts the experiments on my instructions.As, for example,a clear concept of velocity can be given only through statements on time and space,so in my opinion,the complete determination of the intensity of the Earth’s magnetism requires to specify(1)a weight¼p,(2)a length¼r,and then the Earth’s magnetism can be expressed byffiffiffiffiffiffiffip=rp.”After minor adjustment to the units,the experiment was completed in May1832,when the horizontal intensity(H)at Göttingen was found to be1.7820mg1/2mm–1/2s–1(17820nT).The experimentThe experiment was in two parts.In the vibration experiment(Figure G2) magnet A was set oscillating in a horizontal plane by deflecting it from magnetic north.The period of oscillations was determined at different small amplitudes,and from these the period t0of infinite-simal oscillations was deduced.This gave a measure of MH,where M denotes the magnetic moment of magnet A:MH¼4p2I=t20The moment of inertia,I,of the oscillating part is difficult to deter-mine directly,so Gauss used the ingenious idea of conductingtheFigure G2The vibration experiment.Magnet A is suspended from a silk fiber F It is set swinging horizontally and the period of an oscillation is obtained by timing an integral number of swings with clock C,using telescope T to observe the scale S reflected in mirror M.The moment of inertia of the oscillating part can be changed by a known amount by hanging weights W from the rodR. 278GAUSS’DETERMINATION OF ABSOLUTE INTENSITYexperiment for I and then I þD I ,where D I is a known increment obtained by hanging weights at a known distance from the suspension.From several measures of t 0with different values of D I ,I was deter-mined by the method of least squares (another of Gauss ’s original methods).In the deflection experiment,magnet A was removed from the suspension and replaced with magnet B.The ratio M /H was measured by the deflection of magnet B from magnetic north,y ,produced by magnet A when placed in the same horizontal plane as B at distance d magnetic east (or west)of the suspension (Figure G3).This required knowledge of the magnetic intensity due to a bar magnet.Gauss deduced that the intensity at distance d on the axis of a dipole is inversely proportional to d 3,but that just one additional term is required to allow for the finite length of the magnet,giving 2M (1þk/d 2)/d 3,where k denotes a small constant.ThenM =H ¼1=2d 3ð1Àk =d 2Þtan y :The value of k was determined,again by the method of least squares,from the results of a number of measures of y at different d .From MH and M /H both M and,as required by Gauss,H could readily be deduced.Present methodsWith remarkably little modification,Gauss ’s experiment was devel-oped into the Kew magnetometer,which remained the standard means of determining absolute H until electrical methods were introduced in the 1920s.At some observatories,Kew magnetometers were still in use in the 1980s.Nowadays absolute intensity can be measured in sec-onds with a proton magnetometer and without the considerable time and experimental skill required by Gauss ’s method.Stuart R.C.MalinBibliographyGauss,C.F.,1833.Intensitas vis magneticae terrestris ad mensuram absolutam revocata.Göttingen,Germany.Malin,S.R.C.,1982.Sesquicentenary of Gauss ’s first measurement of the absolute value of magnetic intensity.Philosophical Transac-tions of the Royal Society of London ,A 306:5–8.Malin,S.R.C.,and Barraclough,D.R.,1982.150th anniversary of Gauss ’s first absolute magnetic measurement.Nature ,297:285.Cross-referencesGauss,Carl Friedrich (1777–1855)Geomagnetism,History of Gilbert,William (1544–1603)Humboldt,Alexander von (1759–1859)Instrumentation,History ofGAUSS,CARL FRIEDRICH (1777–1855)Amongst the 19th century scientists working in the field of geomag-netism,Carl Friedrich Gauss was certainly one of the most outstanding contributors,who also made very fundamental contributions to the fields of mathematics,astronomy,and geodetics.Born in April 30,1777in Braunschweig (Germany)as the son of a gardener,street butcher,and mason Johann Friderich Carl,as he was named in the certificate of baptism,already in primary school at the age of nine perplexed his teacher J.G.Büttner by his innovative way to sum up the numbers from 1to ter Gauss used to claim that he learned manipulating numbers earlier than being able to speak.In 1788,Gauss became a pupil at the Catharineum in Braunschweig,where M.C.Bartels (1769–1836)recognized his outstanding mathematical abilities and introduced Gauss to more advanced problems of mathe-matics.Gauss proved to be an exceptional pupil catching the attention of Duke Carl Wilhelm Ferdinand of Braunschweig who provided Gauss with the necessary financial support to attend the Collegium Carolinum (now the Technical University of Braunschweig)from 1792to 1795.From 1795to 1798Gauss studied at the University of Göttingen,where his number theoretical studies allowed him to prove in 1796,that the regular 17-gon can be constructed using a pair of compasses and a ruler only.In 1799,he received his doctors degree from the University of Helmstedt (close to Braunschweig;closed 1809by Napoleon)without any oral examination and in absentia .His mentor in Helmstedt was J.F.Pfaff (1765–1825).The thesis submitted was a complete proof of the fundamental theorem of algebra.His studies on number theory published in Latin language as Disquitiones arithi-meticae in 1801made Carl Friedrich Gauss immediately one of the leading mathematicians in Europe.Gauss also made further pioneering contributions to complex number theory,elliptical functions,function theory,and noneuclidian geometry.Many of his thoughts have not been published in regular books but can be read in his more than 7000letters to friends and colleagues.But Gauss was not only interested in mathematics.On January 1,1801the Italian astronomer G.Piazzi (1746–1820)for the first time detected the asteroid Ceres,but lost him again a couple of weeks later.Based on completely new numerical methods,Gauss determined the orbit of Ceres in November 1801,which allowed F.X.von Zach (1754–1832)to redetect Ceres on December 7,1801.This prediction made Gauss famous next to his mathematical findings.In 1805,Gauss got married to Johanna Osthoff (1780–1809),who gave birth to two sons,Joseph and Louis,and a daughter,Wilhelmina.In 1810,Gauss married his second wife,Minna Waldeck (1788–1815).They had three more children together,Eugen,Wilhelm,and Therese.Eugen Gauss later became the founder and first president of the First National Bank of St.Charles,Missouri.Carl Friedrich Gauss ’interest in the Earth magnetic field is evident in a letter to his friend Wilhelm Olbers (1781–1862)as early as 1803,when he told Olbers that geomagnetism is a field where still many mathematical studies can be done.He became more engaged in geo-magnetism after a meeting with A.von Humboldt (1769–1859)and W.E.Weber (1804–1891)in Berlin in 1828where von Humboldt pointed out to Gauss the large number of unsolved problems in geo-magnetism.When Weber became a professor of physics at the Univer-sity of Göttingen in 1831,one of the most productive periods intheFigure G3The deflection experiment.Suspended magnet B is deflected from magnetic north by placing magnet A east or west (magnetic)of it at a known distance d .The angle of deflection y is measured by using telescope T to observe the scale S reflected in mirror M.GAUSS,CARL FRIEDRICH (1777–1855)279field of geomagnetism started.In1832,Gauss and Weber introduced the well-known Gauss system according to which the magnetic field unit was based on the centimeter,the gram,and the second.The Mag-netic Observatory of Göttingen was finished in1833and its construc-tion became the prototype for many other observatories all over Europe.Gauss and Weber furthermore developed and improved instru-ments to measure the magnetic field,such as the unifilar and bifilar magnetometer.Inspired by A.von Humboldt,Gauss and Weber realized that mag-netic field measurements need to be done globally with standardized instruments and at agreed times.This led to the foundation of the Göttinger Magnetische Verein in1836,an organization without any for-mal structure,only devoted to organize magnetic field measurements all over the world.The results of this organization have been published in six volumes as the Resultate aus den Beobachtungen des Magnetischen Vereins.The issue of1838contains the pioneering work Allgemeine Theorie des Erdmagnetismus where Gauss introduced the concept of the spherical harmonic analysis and applied this new tool to magnetic field measurements.His general theory of geomagnetism also allowed to separate the magnetic field into its externally and its internally caused parts.As the external contributions are nowadays interpreted as current systems in the ionosphere and magnetosphere Gauss can also be named the founder of magnetospheric research.Publication of the Resultate ceased in1843.W.E.Weber together with such eminent professors of the University of Göttingen as Jacob Grimm(1785–1863)and Wilhelm Grimm(1786–1859)had formed the political group Göttingen Seven protesting against constitutional violations of King Ernst August of Hannover.As a consequence of these political activities,Weber and his colleagues were dismissed. Though Gauss tried everything to bring back Weber in his position he did not succeed and Weber finally decided to accept a chair at the University of Leipzig in1843.This finished a most fruitful and remarkable cooperation between two of the most outstanding contribu-tors to geomagnetism in the19th century.Their heritage was not only the invention of the first telegraph station in1833,but especially the network of36globally operating magnetic observatories.In his later years Gauss considered to either enter the field of bota-nics or to learn another language.He decided for the language and started to study Russian,already being in his seventies.At that time he was the only person in Göttingen speaking that language fluently. Furthermore,he was asked by the Senate of the University of Göttingen to reorganize their widow’s pension system.This work made him one of the founders of insurance mathematics.In his final years Gauss became fascinated by the newly built railway lines and supported their development using the telegraph idea invented by Weber and himself.Carl Friedrich Gauss died on February23,1855as a most respected citizen of his town Göttingen.He was a real genius who was named Princeps mathematicorum already during his life time,but was also praised for his practical abilities.Karl-Heinz GlaßmeierBibliographyBiegel,G.,and K.Reich,Carl Friedrich Gauss,Braunschweig,2005. Bühler,W.,Gauss:A Biographical study,Berlin,1981.Hall,T.,Carl Friedrich Gauss:A Biography,Cambridge,MA,1970. Lamont,J.,Astronomie und Erdmagnetismus,Stuttgart,1851. Cross-referencesHumboldt,Alexander von(1759–1859)Magnetosphere of the Earth GELLIBRAND,HENRY(1597–1636)Henry Gellibrand was the eldest son of a physician,also Henry,and was born on17November1597in the parish of St.Botolph,Aldersgate,London.In1615,he became a commoner at Trinity Col-lege,Oxford,and obtained a BA in1619and an MA in1621.Aftertaking Holy Orders he became curate at Chiddingstone,Kent,butthe lectures of Sir Henry Savile inspired him to become a full-timemathematician.He settled in Oxford,where he became friends withHenry Briggs,famed for introducing logarithms to the base10.Itwas on Briggs’recommendation that,on the death of Edmund Gunter,Gellibrand succeeded him as Gresham Professor of Astronomy in1627—a post he held until his death from a fever on16February1636.He was buried at St.Peter the Poor,Broad Street,London(now demolished).Gellibrand’s principal publications were concerned with mathe-matics(notably the completion of Briggs’Trigonometrica Britannicaafter Briggs died in1630)and navigation.But he is included herebecause he is credited with the discovery of geomagnetic secular var-iation.The events leading to this discovery are as follows(for furtherdetails see Malin and Bullard,1981).The sequence starts with an observation of magnetic declinationmade by William Borough,a merchant seaman who rose to“captaingeneral”on the Russian trade route before becoming comptroller ofthe Queen’s Navy.The magnetic observation(Borough,1581,1596)was made on16October1580at Limehouse,London,where heobserved the magnetic azimuth of the sun as it rose through sevenfixed altitudes in the morning and as it descended through the samealtitudes in the afternoon.The mean of the two azimuths for each alti-tude gives a measure of magnetic declination,D,the mean of which is11 190EÆ50rms.Despite the small scatter,the value could have beenbiased by site or compass errors.Some40years later,Edmund Gunter,distinguished mathematician,Gresham Professor of Astronomy and inventor of the slide rule,foundD to be“only6gr15m”(6 150E)“as I have sometimes found it oflate”(Gunter,1624,66).The exact date(ca.1622)and location(prob-ably Deptford)of the observation are not stated,but it alerted Gunterto the discrepancy with Borough’s measurement.To investigatefurther,Gunter“enquired after the place where Mr.Borough observed,and went to Limehouse with...a quadrant of three foot Semidiameter,and two Needles,the one above6inches,and the other10inches long ...towards the night the13of June1622,I made observation in sev-eral parts of the ground”(Gunter,1624,66).These observations,witha mean of5 560EÆ120rms,confirmed that D in1622was signifi-cantly less than had been measured by Borough in1580.But was thisan error in the earlier measure,or,unlikely as it then seemed,was Dchanging?Unfortunately Gunter died in1626,before making anyfurther measurements.When Gellibrand succeeded Gunter as Gresham Professor,allhe required to do to confirm a major scientific discovery was towait a few years and then repeat the Limehouse observation.Buthe chose instead to go to the site of Gunter’s earlier observationin Deptford,where,in June1633,Gellibrand found D to be“muchless than5 ”(Gellibrand,1635,16).He made a further measurement of D on the same site on June12,1634and“found it not much to exceed4 ”(Gellibrand,1635,7),the published data giving4 50 EÆ40rms.His observation of D at Paul’s Cray on July4,1634adds little,because it is a new site.On the strength of these observations,he announced his discovery of secular variation(Gellibrand,1635,7and 19),but the reader may decide how much of the credit should go to Gunter.Stuart R.C.Malin280GELLIBRAND,HENRY(1597–1636)BibliographyBorough,W.,1581.A Discourse of the Variation of the Compass,or Magnetical Needle.(Appendix to R.Norman The newe Attractive).London:Jhon Kyngston for Richard Ballard.Borough,W.,1596.A Discourse of the Variation of the Compass,or Magnetical Needle.(Appendix to R.Norman The newe Attractive).London:E Allde for Hugh Astley.Gellibrand,H.,1635.A Discourse Mathematical on the Variation of the Magneticall Needle.Together with its admirable Diminution lately discovered.London:William Jones.Gunter,E.,1624.The description and use of the sector,the crosse-staffe and other Instruments.First booke of the crosse-staffe.London:William Jones.Malin,S.R.C.,and Bullard,Sir Edward,1981.The direction of the Earth’s magnetic field at London,1570–1975.Philosophical Transactions of the Royal Society of London,A299:357–423. Smith,G.,Stephen,L.,and Lee,S.,1967.The Dictionary of National Biography.Oxford:University Press.Cross-referencesCompassGeomagnetic Secular VariationGeomagnetism,History ofGEOCENTRIC AXIAL DIPOLE HYPOTHESISThe time-averaged paleomagnetic fieldPaleomagnetic studies provide measurements of the direction of the ancient geomagnetic field on the geological timescale.Samples are generally collected at a number of sites,where each site is defined as a single point in time.In most cases the time relationship between the sites is not known,moreover when samples are collected from a stratigraphic sequence the time interval between the levels is also not known.In order to deal with such data,the concept of the time-averaged paleomagnetic field is used.Hospers(1954)first introduced the geocentric axial dipole hypothesis(GAD)as a means of defining this time-averaged field and as a method for the analysis of paleomag-netic results.The hypothesis states that the paleomagnetic field,when averaged over a sufficient time interval,will conform with the field expected from a geocentric axial dipole.Hospers presumed that a time interval of several thousand years would be sufficient for the purpose of averaging,but many studies now suggest that tens or hundreds of thousand years are generally required to produce a good time-average. The GAD model is a simple one(Figure G4)in which the geomag-netic and geographic axes and equators coincide.Thus at any point on the surface of the Earth,the time-averaged paleomagnetic latitude l is equal to the geographic latitude.If m is the magnetic moment of this time-averaged geocentric axial dipole and a is the radius of the Earth, the horizontal(H)and vertical(Z)components of the magnetic field at latitude l are given byH¼m0m cos l;Z¼2m0m sin l;(Eq.1)and the total field F is given byF¼ðH2þZ2Þ1=2¼m0m4p a2ð1þ3sin2lÞ1=2:(Eq.2)Since the tangent of the magnetic inclination I is Z/H,thentan I¼2tan l;(Eq.3)and by definition,the declination D is given byD¼0 :(Eq.4)The colatitude p(90 minus the latitude)can be obtained fromtan I¼2cot pð0p180 Þ:(Eq.5)The relationship given in Eq. (3) is fundamental to paleomagnetismand is a direct consequence of the GAD hypothesis.When applied toresults from different geologic periods,it enables the paleomagneticlatitude to be derived from the mean inclination.This relationshipbetween latitude and inclination is shown in Figure G5.Figure G5Variation of inclination with latitude for a geocentricdipole.GEOCENTRIC AXIAL DIPOLE HYPOTHESIS281Paleom a gnetic polesThe positio n where the time-averaged dipole axis cuts the surface of the Earth is called the paleomagnetic pole and is defined on the present latitude-longitude grid. Paleomagnetic poles make it possible to com-pare results from different observing localities, since such poles should represent the best estimate of the position of the geographic pole.These poles are the most useful parameter derived from the GAD hypothesis. If the paleomagnetic mean direction (D m , I m ) is known at some sampling locality S, with latitude and longitude (l s , f s ), the coordinates of the paleomagnetic pole P (l p , f p ) can be calculated from the following equations by reference to Figure G6.sin l p ¼ sin l s cos p þ cos l s sin p cos D m ðÀ90 l p þ90 Þ(Eq. 6)f p ¼ f s þ b ; when cos p sin l s sin l porf p ¼ f s þ 180 À b ; when cos p sin l s sin l p (Eq. 7)wheresin b ¼ sin p sin D m = cos l p : (Eq. 8)The paleocolatitude p is determined from Eq. (5). The paleomagnetic pole ( l p , f p ) calculated in this way implies that “sufficient ” time aver-aging has been carried out. What “sufficient ” time is defined as is a subject of much debate and it is always difficult to estimate the time covered by the rocks being sampled. Any instantaneous paleofield direction (representing only a single point in time) may also be con-verted to a pole position using Eqs. (7) and (8). In this case the pole is termed a virtual geomagnetic pole (VGP). A VGP can be regarded as the paleomagnetic analog of the geomagnetic poles of the present field. The paleomagnetic pole may then also be calculated by finding the average of many VGPs, corresponding to many paleodirections.Of course, given a paleomagnetic pole position with coordinates (l p , f p ), the expected mean direction of magnetization (D m , I m )at any site location (l s , f s ) may be also calculated (Figure G6). The paleocolatitude p is given bycos p ¼ sin l s sin l p þ cos l s cos l p cos ðf p À f s Þ; (Eq. 9)and the inclination I m may then be calculated from Eq. (5). The corre-sponding declination D m is given bycos D m ¼sin l p À sin l s cos pcos l s sin p; (Eq. 10)where0 D m 180 for 0 (f p – f s ) 180and180 < D m <360for 180 < (f p –f s ) < 360 .The declination is indeterminate (that is any value may be chosen)if the site and the pole position coincide. If l s ¼Æ90then D m is defined as being equal to f p , the longitude of the paleomagnetic pole.Te s ting the GAD hy p othesis Tim e scale 0– 5 MaOn the timescale 0 –5 Ma, little or no continental drift will have occurred, so it was originally thought that the observation that world-wide paleomagnetic poles for this time span plotted around the present geographic indicated support for the GAD hypothesis (Cox and Doell,1960; Irving, 1964; McElhinny, 1973). However, any set of axial mul-tipoles (g 01; g 02 ; g 03 , etc.) will also produce paleomagnetic poles that cen-ter around the geographic pole. Indeed, careful analysis of the paleomagnetic data in this time interval has enabled the determination of any second-order multipole terms in the time-averaged field (see below for more detailed discussion of these departures from the GAD hypothesis).The first important test of the GAD hypothesis for the interval 0 –5Ma was carried out by Opdyke and Henry (1969),who plotted the mean inclinations observed in deep-sea sediment cores as a function of latitude,showing that these observations conformed with the GAD hypothesis as predicted by Eq. (3) and plotted in Figure G5.Testing the axial nature of the time-averaged fieldOn the geological timescale it is observed that paleomagnetic poles for any geological period from a single continent or block are closely grouped indicating the dipole hypothesis is true at least to first-order.However,this observation by itself does not prove the axial nature of the dipole field.This can be tested through the use of paleoclimatic indicators (see McElhinny and McFadden,2000for a general discus-sion).Paleoclimatologists use a simple model based on the fact that the net solar flux reaching the surface of the Earth has a maximum at the equator and a minimum at the poles.The global temperature may thus be expected to have the same variation.The density distribu-tion of many climatic indicators (climatically sensitive sediments)at the present time shows a maximum at the equator and either a mini-mum at the poles or a high-latitude zone from which the indicator is absent (e.g.,coral reefs,evaporates,and carbonates).A less common distribution is that of glacial deposits and some deciduous trees,which have a maximum in polar and intermediate latitudes.It has been shown that the distributions of paleoclimatic indicators can be related to the present-day climatic zones that are roughly parallel with latitude.Irving (1956)first suggested that comparisons between paleomag-netic results and geological evidence of past climates could provide a test for the GAD hypothesis over geological time.The essential point regarding such a test is that both paleomagnetic and paleoclimatic data provide independent evidence of past latitudes,since the factors con-trolling climate are quite independent of the Earth ’s magnetic field.The most useful approach is to compile the paleolatitude values for a particular occurrence in the form of equal angle or equalareaFigure G6Calculation of the position P (l p ,f p )of thepaleomagnetic pole relative to the sampling site S (l s ,f s )with mean magnetic direction (D m ,I m ).282GEOCENTRIC AXIAL DIPOLE HYPOTHESIS。

土地整治工程专业英语IntroductionLand reclamation, also known as land improvement or land rehabilitation, refers to the process of restoring and enhancing degraded land to a more productive state. This practice plays a vital role in sustainable development, as it helps to improve soil fertility, prevent erosion, and promote land utilization. In this document, we will explore the key concepts and terminology associated with land reclamation engineering.1. Land DegradationBefore delving into the details of land reclamation, itis crucial to understand the concept of land degradation. Land degradation refers to the deterioration of land quality, usually caused by natural processes or human activities. This degradation can result in reduced soil fertility, decreased biodiversity, and the loss of valuable ecosystem services. Land reclamation aims to reverse or mitigate land degradation and restore the land's productivity.2. Objectives of Land ReclamationThe primary objectives of land reclamation engineering are to improve soil quality, prevent soil erosion, and enhance land productivity. This is achieved through various techniques, such as soil amelioration, erosion control measures, and the introduction of appropriate vegetation. By restoring the land's fertility and stability, land reclamation helps create favorable conditions foragricultural activities, urban development, and ecological restoration.3. Techniques and MethodsLand reclamation engineering involves the implementation of various techniques and methods to restore and improve degraded land. These include:- Soil Amelioration: Soil amelioration aims to enhance soil fertility by adding organic matter, nutrients, and amendments to improve the soil's physical, chemical, and biological properties. This can be achieved through techniques such as soil aeration, nutrient supplementation, and pH adjustment.- Erosion Control: Erosion control measures are crucial in preventing soil erosion, which can lead to the loss of topsoil and reduced land productivity. Techniques such as contour plowing, terracing, and the implementation of erosion control structures help to minimize soil erosion and promote soil conservation.- Vegetation Restoration: The introduction of appropriate vegetation plays a crucial role in land reclamation. Selecting and planting suitable plant species can stabilize the soil, enhance water retention, and improve overall ecosystem resilience. Native plant species are often preferred to restore the original ecosystem and promote biodiversity.4. Case StudiesTo illustrate the application of land reclamation engineering, let's explore a few case studies:- Mining Sites: Land reclamation is often performed on mining sites after the extraction of mineral resources. By rehabilitating these areas and restoring the land's productivity, the negative environmental impacts of mining activities can be mitigated.- Urban Areas: In densely populated urban areas, land reclamation can help address land scarcity issues. By reclaiming and improving degraded land, urban spaces can be expanded, providing opportunities for development and infrastructure.- Coastal Areas: Coastal land reclamation is commonly employed to create new land for ports, airports, andresidential areas. By reclaiming land from the sea, coastal communities can expand and utilize land resources effectively. ConclusionLand reclamation engineering is a vital discipline that aims to restore and enhance degraded land for sustainable development. Through techniques such as soil amelioration, erosion control, and vegetation restoration, land reclamation helps improve soil quality, prevent erosion, and enhance land productivity. By understanding the concepts and practices associated with land reclamation, professionals in this field can contribute to the sustainable management of land resources.。

基于光能利用效率的区域蒸散量反演模型——以玉米种植区为例苏涛;冯绍元;徐英【摘要】With Jiefang gate irrigation area of Hetao region in Inner Mongolia as the research district,and the biomass,the soil water and the relation equation between them in the measured values as the research foundation,the authors set up a regional evapotranspiration retrieving model based on the Radiation Use Efficiency (RUE).The SEBAL(surface energy balance algorithm for land) model was taken as the referenced model to make a comparative analysis between the regional evapotranspirations in the same period.The results showed that the spatial distributions of evapotranspiration estimated by using the RUE method and the SEBAL model were similar in spatial distribution and texture features,and there only existed insigficant differences between the calculated results of the two models.The correlation coefficient between the RUE method and the SEBAL model was remarkably improved in comparison with that of the DSSAT (decision support system for agrotechnology transfer) method and the SEBAL model.It is also proved that the regional evapotranspiration can be better retrieved by the RUE method,with the retrieving accuracy obviously higher than that of the DSSAT method,and hence this method is a new and effective method for monitoring regional evapotranspiration.%以内蒙古河套地区解放闸灌域为研究区域,以实测生物量与土壤含水量及其关系方程为研究基础,建立了基于光能利用效率(radiation use efficiency,RUE)的区域蒸散量反演模型;以陆面能量平衡(surface energy balance algorithm for land,SEBAL)模型为参考,对反演的同一时期的区域蒸散量进行对比分析.结果表明:RUE与SEBAL模型反演的区域蒸散量在空间分布和纹理特征方面具有相似性且相关性较高,决定系数高于农业技术推广支持系统(decision support system for agrotechnology transfer,DSSAT)与SEBAL的;基于RUE建立的区域蒸散量反演模型能够较好地反映区域蒸散量,在监测区植被(或作物)单一的前提下,是一种有效方法.【期刊名称】《国土资源遥感》【年(卷),期】2013(025)003【总页数】6页(P14-19)【关键词】区域蒸散量;光能利用效率(RUE);DSSAT;遥感;生物量【作者】苏涛;冯绍元;徐英【作者单位】扬州大学水利科学与工程学院,扬州225009;扬州大学水利科学与工程学院,扬州225009;扬州大学水利科学与工程学院,扬州225009【正文语种】中文【中图分类】S152.7;TP790 引言发展节水农业，实现水资源可持续利用，是保障中国水和粮食安全的重要战略举措和必然选择。