Return-period flows and rainfall
Generalised extreme-value or peaks-over-threshold distributions are fitted to annual maxima, with confidence intervals reported alongside the point estimate.
Extreme value theory and 尾部风险 study the behaviour of rare, high-impact events. They provide methods to estimate the magnitude and frequency of extremes beyond the range of observed data. In water, climate and hazards and 关键基础设施, extreme value methods set design levels and capital buffers for rare events. Tail dependence analysis reveals when extremes in different 系统 tend to occur together. The canonical description is on STEM Commons.
Generalised extreme-value or peaks-over-threshold distributions are fitted to annual maxima, with confidence intervals reported alongside the point estimate.
Short records are pooled across hydrologically similar catchments so ungauged sites inherit a defensible frequency curve.
Dependence between rainfall and surge, or drought and heat, is modelled with copulas; trends in the record are tested and, where present, the frequency curve is allowed to move.
来自 NASA GIBS 的尼罗河流域降雨、洪水和根区土壤湿度数据。每个图层都标注各自的日期。
交互式地图需要JavaScript;图层列表和来源见下文。
图层 3
本页面的当前水情
键盘操作,地图获得焦点时
按住 Ctrl 或 ⌘ 并滚动以缩放
最新可用
NASA GIBS / EOSDIS · ASTER GDEM (METI, NASA) · Blue Marble (NASA) · © OpenStreetMap贡献者 (ODbL) · Natural Earth
正在加载最新的NASA影像。
拖动以移动。按住 Ctrl 或 ⌘ 并滚动、双指缩放或使用按钮缩放;悬停可查看指针下的数值;重置可返回该区域。
当前的水情,以尼罗河流域为范围。NASA 发布的卫星和模型产品,各带自己的日期。它们是指标,而非对任何地点的评估。
图层与日期
Datasets and records used by extreme value theory and 尾部风险 on this platform, with the role each plays and the label its values carry. Sources are listed in 来源登记册.
| 数据 | 角色 | 标签 |
|---|---|---|
| Annual maximum series | Distribution fitting | 观测 |
| Peaks over threshold | Distribution fitting | 观测 |
| Regional catchment descriptors | Pooling groups | 估算 |
| Climate model projections | Non-stationary scenarios | 模型生成 |
Rain becomes runoff by the curve number method, drains each sub-catchment through a linear reservoir and travels down the main stem by Muskingum routing; play it to watch the flood wave move and flatten. Teaching model with stated illustrative values, not a prediction. The map on this page shows The Nile Basin; the model itself is not tied to a place.
控制措施
读数
| Hour | Outlet (m³/s) | Unrouted (m³/s) | Upper reach (m³/s) |
|---|---|---|---|
| 2.4 | 0.0 | 678.9 | 0.0 |
| 12.0 | 308.3 | 1,151.4 | 181.8 |
| 21.6 | 452.4 | 35.1 | 73.7 |
| 31.2 | 363.3 | 1.1 | 11.1 |
| 40.8 | 198.8 | 0.0 | 1.5 |
| 50.4 | 79.3 | 0.0 | 0.2 |
| 60.0 | 25.4 | 0.0 | 0.0 |
| 69.6 | 6.9 | 0.0 | 0.0 |
| 79.2 | 1.7 | 0.0 | 0.0 |
| 88.8 | 0.4 | 0.0 | 0.0 |
| 98.4 | 0.1 | 0.0 | 0.0 |
| 108.0 | 0.0 | 0.0 | 0.0 |
| 117.6 | 0.0 | 0.0 | 0.0 |
| 127.2 | 0.0 | 0.0 | 0.0 |
| 136.8 | 0.0 | 0.0 | 0.0 |
The model runs on the teaching values set by the controls. To calibrate it for a place, read it against these admitted layers and series, which this page’s map can draw:
贯穿六大支柱,由 Nexus Consortium 牵头
Fits are checked with diagnostic plots, goodness-of-fit tests and out-of-sample comparison. Sensitivity to threshold and record length is reported.
| 核查 | 如何开展 |
|---|---|
| Goodness of fit | Several distributions are compared; the choice and its effect on the estimate are reported |
| Bootstrap uncertainty | Confidence intervals are resampled, not assumed |
| Stationarity tests | Trend and change-point tests precede any quoted 重现期 |
Extrapolation far beyond the data is highly uncertain. Changing climates and markets violate stationarity assumptions.
Assembled from the Nexus Standards area profile 水风险标准: the hazards it names, the 系统 and sectors that carry the loss, the controls that dampen it and the data that observe it. Choose the components, pick an initiating hazard and step through the cascade. The Map view places the run on an example geography with open data. Every coupling weight is a stated assumption you can change. A teaching model, not a forecast, an assessment or a certification. To model a place of your own choosing, open the full System Builder.
灾害
控制措施
NS-0 章程与原则NS-1 维持社会运转的 UNI 与制品目录(语法 v0.2:领域、部门、区域和环境分段)NS-3 风险记录 UNI(语法、旧编码对照、分配机构)NS-3b 数据集与产品元数据规范(STAC、DCAT、PROV-O)NS-9 情境 UNI(部署、实例、计划实例)NS-10 政策和条款(机器可读的义务:定义、约束、评估和执行)NS-11 验证与监测(证据、证明、零信任符合性观测)NRS-U28 宇宙 platform profile: Water NexusNRS-H61 危害族:级联失效(NHS-1 sys.cascade)NRS-K42 领域包概况:跨境流域(DOMAIN-042)NRS-N1 水风险与韧性NRS-N7 水-能源-粮食-卫生-生物多样性-基础设施关联耦合NRS-H62 危害类别:复合与多危害事件(NHS-1 sys.compound)观测
示例地理范围
选择背景
部门 · 城市洪水压力
支柱 · 城市洪水KPI
在此背景之中依赖或移交关系,越粗越强不在此背景之内
计划年度所有阶段
背景
城市洪水
被淹的街道会同时损毁变电站、泵站和诊所通道;电力中断时,饮用水也会中断。
W · E · I · F · H · B
风险
将鼠标悬停在某个角、某条线或某一行上,可在两侧追踪其走向。
路径
应用于城市洪涝
L · F · U · S · R · A
响应
期望值
将鼠标悬停在支柱、线条或行上,查看其应用方式。
A:基于典型城市区域教学用值的教学级联(冲击 0.6,增益 0.35,四轮),并非实测值。B:示意性应用及每个支柱所负责的关键绩效指标;数值为已发布并注明出处的基准,并非预测。开放事件:NASA EONET,实时。
模型、其假设、数据和不确定性,以科学家或工程师会核查的形式呈现。结构遵循已发表的方法。所取数值仅为示意,不是研究发现。
The couplings between the systems in extreme value statistics for floods and droughts: signs of influence, a reinforcing and a balancing loop, and cross-links where stress jumps.
报告 is the Consortium’s quarterly publication. What you know about this subject can become evidence, a case or a correction in the next edition, credited to you and published under CC BY 4.0 where it is your own work.
切勿发送个人数据、敏感基础设施细节或您无权分享的任何内容。贡献在使用前会经过审查;发送贡献不赋予署名权或编辑权,赞助也绝不能换取研究结论。
本网站上的地图、数据和图表仅作为背景和一般信息展示。它们不是建议、预测或预警;信息的局限见免责声明和数据说明。
This site uses only strictly necessary cookies to work and to remember your privacy choices. Nothing loads from other companies, and we never sell or share your personal information.
This site uses only strictly necessary cookies to work and to remember your privacy choices. Nothing loads from other companies, and we never sell or share your personal information. We run no advertising. You can review your choices at any time through Privacy choices at the foot of every page.