Modeling Uncertainty In The Earth Sciences: Introduction

1y ago
48 Views
2 Downloads
970.91 KB
20 Pages
Last View : 4d ago
Last Download : 2m ago
Upload by : Alexia Money
Transcription

Modeling Uncertainty in the Earth Sciences:IntroductionModeling Uncertainty in the Earth SciencesJef CaersStanford University

What is this book about?Modeling uncertainty in the Earth sciences

June 26, 2010: CNN headlines“Tropical storm plus oil slick equal uncertainty”BP DeepHorizon spill?Decision question: “Will BP evacuate the clean-up crew knowing that shouldevacuation requires at least 3 days, with the consequence of more oil spilling in thegolf from the deep-water well, or, will BP leave the crew, possibly exposing them totropical storm Alex, which may or may not become a hurricane?” A simple question:what is the best decision in this case?

Case studyDecision to be made:relocation of farms, industry, city development etcto protect groundwater

ContextDanish Government’s 10-point program (1994)Pesticides dangerous to health and environment shall be removed from the marketPesticide tax - the consumption of pesticides shall be halvedNitrate pollution shall be halved before 2000Organic farming shall be encouragedProtection of areas of special interest for drinking waterNew Soil Contamination Act - waste deposits shall be cleaned upIncreased afforestation and restoration of nature to protect groundwaterStrengthening of the EU achievementsIncreased control of groundwater and drinking water qualityDialogue with the farmers and their organisationsSource: e groundwaterprotection print.pdf

Decision making under uncertainty Groundwater flow depends on many factors Regional flow Geological heterogeneity of the subsurface Pumping conditions / well locationsABAzBMoraine clayClay lensNon-ValleyValley

Decision making Decision making requires a conscious irrevocableallocation of resources to achieve desired objectives Objectives may be conflicting Not all objectives can be easily put in numbers Requires a specification of “risk” and “value” Presence of uncertainty A good decision does not always lead to a good outcome

Why is there uncertainty? Uncertainty is due to the lack of knowledge toexhaustively and deterministically determine allaspects of the studied phenomenon In this case: geological understanding will not be ableto reconstruct perfectly the geological processes thattook place, because either: We do not fully understand all or some of the geological processescreating valleys (global uncertainty) Even if that is the case, we do not have enough information to uniquelyconstrain these processes to know where glacial valleys were created(local uncertainty)

Data collection

Sources of uncertainty Measurement error Interpretation and processing of raw measurements Interpretation of the geological setting from data Spatial uncertainty Uncertainty on the physical laws governing flow

Elements critical to modeling uncertainty Decision making context Modeling uncertainty always requires a context Geological heterogeneity / spatio-temporal variation Establish understanding of the medium you aremodeling Data collection and value (or lack thereof) ofinformation Data may constrain models of uncertainty and mayimprove decisions

Nature of modeling uncertaintyin the Earth Sciences Needs to be application tailored Several sources of uncertainty Measurements and their interpretationGeological settingSpatial variationResponse uncertainty Uncertainty assessment is subjective Dealing with a high-dimensional / large problem Mathematical challenges Memory demanding CPU demanding Need to deal with several data sources

Aim of this bookModeling uncertainty in the Earth sciences

Aim To be practical What matters? No theory, example-driven To discuss principles, concept and tools of modelinguncertainty To discuss the practice of such modeling with actualsoftware To teach the why/what not exactly how it works

Book contentModeling uncertainty in the Earth sciences

Modeling To understand modeling uncertainty we need tounderstand how one builds a single modelModel of Glacial Valley An Earth model has A structural component Properties filling these structures Data constraining what is being built

Modeling uncertainty Uncertainty of Earth models will be represented bybuilding several alternative models Teach the concept of randomization and how thisleads to the constructing alternative Earth models

Engineering the Earth under uncertainty Decision analysis for including such uncertainty inmaking decision about engineering operationsNWNERechargeat location 1NWNENWnorechargeNErechargeat location 2 Figure out what matters for such decision

Value of informationTo determine the value of gathering data prior toactually gathering the data, this value will depend on The particular decision problem at hand The uncertainty prior to gathering the data The physics underlying the measurement The reliability of the measurement device inresolving spatial variation or key geological drivers

Book content Decision making under uncertainty Spatial continuity and uncertainty Structural modeling and uncertainty Response uncertainty Value of information

Nature of modeling uncertainty in the Earth Sciences Needs to be application tailored Several sources of uncertainty Measurements and their interpretation Geological setting Spatial variation Response uncertainty Uncertainty assessment is subjective Dealing with a high-dimensional / large problem Mathematical challenges

Related Documents:

May 02, 2018 · D. Program Evaluation ͟The organization has provided a description of the framework for how each program will be evaluated. The framework should include all the elements below: ͟The evaluation methods are cost-effective for the organization ͟Quantitative and qualitative data is being collected (at Basics tier, data collection must have begun)

Silat is a combative art of self-defense and survival rooted from Matay archipelago. It was traced at thé early of Langkasuka Kingdom (2nd century CE) till thé reign of Melaka (Malaysia) Sultanate era (13th century). Silat has now evolved to become part of social culture and tradition with thé appearance of a fine physical and spiritual .

On an exceptional basis, Member States may request UNESCO to provide thé candidates with access to thé platform so they can complète thé form by themselves. Thèse requests must be addressed to esd rize unesco. or by 15 A ril 2021 UNESCO will provide thé nomineewith accessto thé platform via their émail address.

̶The leading indicator of employee engagement is based on the quality of the relationship between employee and supervisor Empower your managers! ̶Help them understand the impact on the organization ̶Share important changes, plan options, tasks, and deadlines ̶Provide key messages and talking points ̶Prepare them to answer employee questions

Dr. Sunita Bharatwal** Dr. Pawan Garga*** Abstract Customer satisfaction is derived from thè functionalities and values, a product or Service can provide. The current study aims to segregate thè dimensions of ordine Service quality and gather insights on its impact on web shopping. The trends of purchases have

Chính Văn.- Còn đức Thế tôn thì tuệ giác cực kỳ trong sạch 8: hiện hành bất nhị 9, đạt đến vô tướng 10, đứng vào chỗ đứng của các đức Thế tôn 11, thể hiện tính bình đẳng của các Ngài, đến chỗ không còn chướng ngại 12, giáo pháp không thể khuynh đảo, tâm thức không bị cản trở, cái được

1.1 Measurement Uncertainty 2 1.2 Test Uncertainty Ratio (TUR) 3 1.3 Test Uncertainty 4 1.4 Objective of this research 5 CHAPTER 2: MEASUREMENT UNCERTAINTY 7 2.1 Uncertainty Contributors 9 2.2 Definitions 13 2.3 Task Specific Uncertainty 19 CHAPTER 3: TERMS AND DEFINITIONS 21 3.1 Definition of terms 22 CHAPTER 4: CURRENT US AND ISO STANDARDS 33

PK-2 Next Generation ELA Standards at a Glance . PK-2 Reading Standards (Literary and Informational Text) Review the . PK, K, 1. st, and 2 nd grade ELA introductions for information regarding: guidance and support, range of student reading experiences, text complexity, English language learners/multilingual learners, and students with disabilities. Key Ideas and Details PK K 1 2 PKR1 .