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

地球科学家发现和预测自然界的行为，部分是通过使用计算机模型。模型用于研究各种现象，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的世界进行比较，模型可以用来发展科学理解。它们也可以用来预测自然在某些条件下的行为。在处理地球表面的地球科学领域，模型开发和使用的一个瓶颈是构建、测试和调试必要的软件所需的工作。该项目通过创建开源软件工具来促进科学研究和发现，科学家可以使用这些工具来更有效地创建、修改或联合收割机计算机模型，这些模型代表了地球表面的一部分及其上发生的过程。该项目将软件开发与用户培训和网络资源相结合，以便产品可以在相关科学界公开获取、记录良好并广泛传播。该项目还有助于K-12，本科生和研究生水平的教育在计算建模和地球表面过程。该项目通过开发一个软件框架，使快速创建，细化和重用的二维（2D）数值模型催化在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多样化的科学和工程领域，涉及我们星球的表面和近表面环境：它的过程，它的管理，以及它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从头开始构建自己独特的模型，重新编码模型的基本构建块，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工时，并且所产生的软件通常是特殊的，记录不佳，并且无法与同一科学界内外的其他软件程序交互，导致失去探索比使用单一模型可以解决的更广泛的科学问题的机会。Landlab模型框架旨在消除这些冗余和失去的机会，同时降低进入数值建模的门槛，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建模块。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共享一组共同的软件元素，尽管它们所包含的过程和尺度范围很广。在流行的科学编程环境中提供这些元素，并提供强大的用户支持和社区参与，有助于加速地球表面各种科学的进步。Landlab建模框架的设计使网格创建，数据存储和过程组件之间的数据共享都是为用户完成的。该框架是通用的，足以使两个过程组件的耦合，无论他们是在一个地球科学的子学科，或他们跨子学科，是相同的。这种架构使探索地球科学中的各种问题变得容易，而不需要太多的编码。此外，模型代码主要是用Python编写的，Python是一种对于普通程序员来说相对容易学习的语言。由于这些属性，Landlab建模框架有可能将计算建模添加到各种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，例如响应气候变化的土地覆盖变化，以及目前需要耦合复杂但难以使用的模型的主题建模，例如沉积物源-汇动态。该项目将生成几个概念验证研究，这些研究本身就很有趣，并展示了建模框架的功能。社区参与是通过在专业场所举办针对水文学家，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诊所和演示来促进的。该小组还支持科学家个人访问这些诊所以外的地方进行现场培训。输入/输出工具允许与相关NSF支持的研究数据兼容。该项目支持四名研究生和三名博士后研究人员，还包括在一个少数民族人口超过50%的社区为五至七年级的女孩举办建模研讨会。

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.