ECMWF reanalysis refers to a comprehensive set of climate data produced by the European Centre for Medium-Range Weather Forecasts (ECMWF) that provides a historical record of the atmosphere, oceans, and land surface. The most notable reanalysis project by ECMWF is the ERA (ECMWF Re-Analysis) series, which includes several versions like ERA-Interim and ERA5.
GO-ESSP, or the Global Ocean Essential Climate Variables (EECVs) for the Earth System Science Partnership, is a framework designed to identify, measure, and monitor essential climate variables that are crucial for understanding the ocean's role in the Earth’s climate system. The initiative focuses on standardized approaches to observing and assessing these climate variables, thereby supporting climate research, modeling, and policy-making.
Matrix multiplication is a fundamental operation in linear algebra and is used in various applications across mathematics, computer science, physics, and engineering. The process involves taking two matrices and producing a third matrix through a specific set of rules.
Iterative refinement is a process commonly used in various fields, including computer science, engineering, and mathematics, to progressively improve a solution or a model by making successive approximations. The general idea involves iterating through a cycle of refinement steps, where each iteration builds upon the results of the previous one, leading to a more accurate or optimized outcome. Here’s a breakdown of how iterative refinement typically works: 1. **Initial Solution**: Start with an initial guess or solution.
Modified Richardson iteration is a technique used to accelerate the convergence of iterative methods for the solution of problems, particularly in numerical linear algebra, such as solving systems of linear equations. The Richardson iteration method itself is based on the idea of correcting the current approximation of the solution to an equation by using a linear correction term.
The Luoshu Square, also known as the Luo Shu or the Lo Shu Square, is an ancient Chinese diagram that is associated with feng shui, numerology, and I Ching practices. It consists of a 3x3 grid where the numbers 1 to 9 are arranged in a specific order such that the sum of the numbers in each row, column, and diagonal equals 15.
Petosiris and Nechepso are figures from ancient Egyptian history, specifically related to the development of astrology and astronomy in the Hellenistic period. Petosiris was an Egyptian priest and astrologer, most noted for his works in the field of astrology during the 2nd century BCE. His writings reflect the integration of Egyptian religious practices with Greek philosophical thought, especially in the context of astrology.
Madeira is an archipelago located in the North Atlantic Ocean, southwest of Portugal. It is an autonomous region of Portugal and consists of several islands, the largest of which is Madeira Island itself, along with Porto Santo, Desertas Islands, and Selvagens Islands. Madeira is known for its stunning natural landscapes, including rugged mountains, lush forests, and a mild climate, which makes it a popular destination for tourists.
NUTS stands for "Nomenclature of Territorial Units for Statistics," which is a hierarchical system for dividing up the economic territory of the European Union and European Economic Area. In the context of the United Kingdom, the NUTS classification consists of multiple levels, with NUTS 1 being the highest level of regional classification. As of the most recent classifications, the NUTS 1 regions of the United Kingdom are: 1. **East Scotland** 2.
Transdanubia is a historical and geographical region located west of the Danube River in Hungary. It is known for its diverse landscapes, which include rolling hills, vineyards, and the picturesque Lake Balaton, the largest freshwater lake in Central Europe. The region features a mix of rural and urban areas, with cities like Székesfehérvár, Veszprém, and Pécs being notable centers.
NUTS, or the Nomenclature of Territorial Units for Statistics, is a hierarchical system for dividing up the economic territory of the European Union and the European Economic Area. The NUTS classification is used for collecting, developing, and analyzing the regional statistics of the EU.
Catalonia is an autonomous community in northeastern Spain, characterized by its distinct culture, history, and language, Catalan. It has its own parliament and government, which have varying degrees of legislative power. The capital of Catalonia is Barcelona, a major cultural and economic center known for its architecture, art, and vibrant lifestyle. Historically, Catalonia has a unique identity that dates back centuries, with its own language, customs, and traditions.
Melilla is a Spanish autonomous city located on the northern coast of Africa, bordering Morocco. It is one of two cities—along with Ceuta—that form part of Spain but are situated on the African continent. Melilla has a strategic location near the Mediterranean Sea and is separated from the Spanish mainland by the Mediterranean waters. The city has a rich history influenced by various cultures, including Berber, Spanish, and other Mediterranean civilizations.
George Dickie is an American philosopher known primarily for his work in aesthetics and the philosophy of art. He is associated with the "institutional theory of art," which he developed in the 1970s. According to this theory, an object is considered art if it is situated within a specific social context or institution that regards it as art. This perspective shifts the focus from intrinsic qualities of the artwork to the social practices and contexts that contribute to its designation as art.
In category theory, a branch of mathematics, a **closed category** typically refers to a category that has certain characteristics related to products, coproducts, and exponentials. However, the term "closed category" can have different interpretations, so it's important to clarify the context. One common context is in the classification of categories based on the existence of certain limits and colimits. A category \( \mathcal{C} \) is said to be **closed** if it has exponential objects.
Combinatorial commutative algebra is a branch of mathematics that merges concepts from commutative algebra with combinatorial techniques and ideas. This field studies algebraic objects (like ideals, rings, and varieties) using combinatorial methods, often involving graph theory, polytopes, and combinatorial configurations.
Commutative algebra is a branch of mathematics that studies commutative rings and their ideals. It serves as a foundational area for algebraic geometry, number theory, and various other fields in both pure and applied mathematics. Here are some key concepts and components of commutative algebra: 1. **Rings and Ideals**: A ring is an algebraic structure equipped with two binary operations, typically addition and multiplication, satisfying certain properties.
In algebraic geometry and commutative algebra, a **complete intersection ring** is associated with a particular kind of algebraic variety, namely those that can be defined as the common zeros of a certain number of polynomials in a polynomial ring. To provide a clearer understanding, let’s go through some definitions step by step. 1. **Algebraic Variety**: An algebraic variety is a geometric object that is the solution set of a system of polynomial equations.

Pinned article: Introduction to the OurBigBook Project

Welcome to the OurBigBook Project! Our goal is to create the perfect publishing platform for STEM subjects, and get university-level students to write the best free STEM tutorials ever.
Everyone is welcome to create an account and play with the site: ourbigbook.com/go/register. We belive that students themselves can write amazing tutorials, but teachers are welcome too. You can write about anything you want, it doesn't have to be STEM or even educational. Silly test content is very welcome and you won't be penalized in any way. Just keep it legal!
We have two killer features:
  1. topics: topics group articles by different users with the same title, e.g. here is the topic for the "Fundamental Theorem of Calculus" ourbigbook.com/go/topic/fundamental-theorem-of-calculus
    Articles of different users are sorted by upvote within each article page. This feature is a bit like:
    • a Wikipedia where each user can have their own version of each article
    • a Q&A website like Stack Overflow, where multiple people can give their views on a given topic, and the best ones are sorted by upvote. Except you don't need to wait for someone to ask first, and any topic goes, no matter how narrow or broad
    This feature makes it possible for readers to find better explanations of any topic created by other writers. And it allows writers to create an explanation in a place that readers might actually find it.
    Figure 1.
    Screenshot of the "Derivative" topic page
    . View it live at: ourbigbook.com/go/topic/derivative
  2. local editing: you can store all your personal knowledge base content locally in a plaintext markup format that can be edited locally and published either:
    This way you can be sure that even if OurBigBook.com were to go down one day (which we have no plans to do as it is quite cheap to host!), your content will still be perfectly readable as a static site.
    Figure 2.
    You can publish local OurBigBook lightweight markup files to either https://OurBigBook.com or as a static website
    .
    Figure 3.
    Visual Studio Code extension installation
    .
    Figure 4.
    Visual Studio Code extension tree navigation
    .
    Figure 5.
    Web editor
    . You can also edit articles on the Web editor without installing anything locally.
    Video 3.
    Edit locally and publish demo
    . Source. This shows editing OurBigBook Markup and publishing it using the Visual Studio Code extension.
    Video 4.
    OurBigBook Visual Studio Code extension editing and navigation demo
    . Source.
  3. https://raw.githubusercontent.com/ourbigbook/ourbigbook-media/master/feature/x/hilbert-space-arrow.png
  4. Infinitely deep tables of contents:
    Figure 6.
    Dynamic article tree with infinitely deep table of contents
    .
    Descendant pages can also show up as toplevel e.g.: ourbigbook.com/cirosantilli/chordate-subclade
All our software is open source and hosted at: github.com/ourbigbook/ourbigbook
Further documentation can be found at: docs.ourbigbook.com
Feel free to reach our to us for any help or suggestions: docs.ourbigbook.com/#contact