Collaborative Research: SI2-SSI: Landlab: A Flexible, Open-Source Modeling Framework for Earth-Surface Dynamics

地球科学家部分地通过使用计算机模型来发现和预测自然界的行为。模型被用来研究广泛的现象，如土壤侵蚀、洪水、植物生长、滑坡发生和许多其他过程。通过将模型计算与真实世界进行比较，可以使用模型来发展科学理解。它们还可以用来预测自然界在特定条件下的行为。在涉及地球表面的地球科学领域，开发和使用模型的一个瓶颈是建立、测试和调试必要的软件所需的努力。该项目通过创建开源软件工具为科学研究和发现做出贡献，科学家可以使用这些工具更有效地创建、修改或组合代表地球表面部分和发生在其上的过程的计算机模型。该项目将软件开发与用户培训和基于网络的资源相结合，从而使这些产品能够在相关科学界内公开获取、充分记录和广泛传播。该项目还有助于K-12、本科生和研究生水平的计算建模和地球表面过程的教育。该项目通过开发一个能够快速创建、改进和重复使用二维(2D)数值模型的软件框架来促进地球表面动力学的研究。地球表面动力学一词指的是一组非常不同的科学和工程领域，涉及我们星球的表面和近表面环境：其过程、管理以及对自然和人为扰动的反应。想要使用地球表面模型的科学家通常会从头开始建立自己独特的模型，对模型的基本构件进行重新编码，而不是利用已经编写的代码。虽然最终的结果可能是新的软件程序，但重写现有代码会损失许多人时，并且所产生的软件通常是独特的、文档记录很少的，并且不能与同一科学界内外的其他软件程序交互，从而导致与使用单一模型解决的问题相比，失去了探索更广泛的科学问题的机会。LandLab模型框架寻求消除这些冗余和失去的机会，同时通过创建一个用户和开发人员友好的软件库，为科学家提供建模地球表面动力学所需的基本构件，同时降低进入数值建模的门槛。该框架利用了这样一个事实，即几乎所有的表面动力学模型都共享一组通用的软件元素，尽管它们包含了广泛的过程和规模。在受欢迎的科学编程环境中提供这些元素，并有强大的用户支持和社区参与，有助于加快地球表面各种科学的进展。LandLab建模框架的设计旨在为用户完成网格创建、数据存储和过程组件之间的数据共享。该框架足够通用，因此两个过程组件的耦合是相同的，无论它们是直接在地学子学科内，还是跨子学科。这种体系结构使得在地球科学中探索广泛的问题变得容易，而不需要太多的编码。此外，模型代码主要是用Python语言编写的，这是一种对临时程序员来说相对容易学习的语言。由于这些特点，LandLab建模框架有可能将计算建模添加到大量地球科学家的工具箱中，并为探索社会相关主题的跨学科地球表面建模扫清道路，例如对气候变化的土地覆盖变化进行探索，以及对目前需要耦合复杂但更难使用的模型的主题进行建模，例如沉淀源到汇的动力学。该项目将生成几个本身很有趣的概念验证研究，并演示建模框架的功能。通过在针对水文学家、沉积学家、临界区科学家以及更广泛的地球和环境科学界的专业场所提供诊所和演示，促进社区参与。该团队还支持科学家个人访问，以便在这些诊所之外进行现场培训。输入/输出工具允许与来自NSF支持的相关研究的数据兼容。该项目支持四名研究生和三名博士后研究人员，还包括为一个少数民族人口超过50%的社区的五到七年级女孩举办模特讲习班。

Earth scientists discover and predict the behavior of the natural world in part through the use of computer models. Models are used to study a wide range of phenomena, such as soil erosion, flooding, plant growth, landslide occurrence, and many other processes. Models can be used to develop scientific understanding by comparing model calculations with the real world. They can also be used to make predictions about how nature will behave under certain conditions. In the areas of geosciences that deal with the earth's surface, one bottleneck in the development and use of models is the effort required to build, test, and debug the necessary software. This project contributes to scientific research and discovery by creating open source software tools that scientists can use to more efficiently create, modify, or combine computer models that represent portions of earth's surface and the processes occurring thereon. The project combines software development with user training and web-based resources, so that the products will be openly accessible, well documented, and widely disseminated within the relevant scientific communities. The project also contributes to K-12, undergraduate, and graduate-level education in computational modeling and earth-surface processes.This project catalyzes research in earth-surface dynamics by developing a software framework that enables rapid creation, refinement, and reuse of two-dimensional (2D) numerical models. The phrase earth-surface dynamics refers to a remarkably diverse group of science and engineering fields that deal with our planet's surface and near-surface environment: its processes, its management, and its responses to natural and human-made perturbations. Scientists who want to use an earth-surface model often build their own unique model from the ground up, re-coding the basic building blocks of their model rather than taking advantage of codes that have already been written. Whereas the end result may be novel software programs, many person-hours are lost rewriting existing code, and the resulting software is often idiosyncratic, poorly documented, and unable to interact with other software programs in the same scientific community and beyond, leading to lost opportunities for exploring an even wider array of scientific questions than those that can be addressed using a single model. The Landlab model framework seeks to eliminate these redundancies and lost opportunities, and simultaneously lower the bar for entry into numerical modeling, by creating a user- and developer-friendly software library that provides scientists with the fundamental building blocks needed for modeling earth-surface dynamics. The framework takes advantage of the fact that nearly all surface-dynamics models share a set of common software elements, despite the wide range of processes and scales that they encompass. Providing these elements in the context of a popular scientific programming environment, with strong user support and community engagement, contributes to accelerating progress in the diverse sciences of the earth's surface.The Landlab modeling framework is designed so that grid creation, data storage, and sharing of data among process components is done for the user. The framework is generic enough so that the coupling of two process components, whether they are squarely within a geoscience subdiscipline, or they cross subdisciplines, is the same. This architecture makes it easy to explore a wide range of questions in the geosciences without the need for much coding. Further, the model code is primarily written in Python, a language that is relatively easy for casual programmers to learn. Because of these attributes, the Landlab modeling framework has the potential to add computational modeling to the toolbox of a wide array of geoscientists, and to clear a path for trans-disciplinary earth-surface modeling that explores societally relevant topics, such as land-cover changes in response to climate change, as well as modeling of topics that currently require the coupling of sophisticated but harder-to-use models, such as sediment source-to-sink dynamics. The project will generate several proof-of-concept studies that are interesting in their own right, and demonstrate the capabilities of the modeling framework. Community engagement is fostered by presenting clinics and demonstrations at professional venues aimed at hydrologists, sedimentologists, critical zone scientists, and the broader earth and environmental sciences community. The team also supports visits by individual scientists for on-site training beyond these clinics. Input/output tools allow compatibility with data from relevant NSF-supported research. The project supports four graduate students and three postdoctoral researchers, and also includes modeling workshops for fifth to seventh grade girls in a community that has a greater than 50% minority population.