The insight of why:Causal inference in Earth system science

The utilization of big Earth data has provided insights into the planet we inhabit in unprecedented dimensions and scales.Unraveling the concealed causal connections within intricate data holds paramount importance for attaining a profound comprehension of the Earth system.Statistical methods founded on correlation have predominated in Earth system science(ESS)for a long time.Nevertheless,correlation does not imply causation,especially when confronted with spurious correlations resulting from big data.Consequently,traditional correlation and regression methods are inadequate for addressing causation related problems in the Earth system.In recent years,propelled by advancements in causal theory and inference methods,particularly the maturity of causal discovery and causal graphical models,causal inference has demonstrated vigorous vitality in various research directions in the Earth system,such as regularities revealing,processes understanding,hypothesis testing,and physical models improving.This paper commences by delving into the origins,connotations,and development of causality,subsequently outlining the principal frameworks of causal inference and the commonly used methods in ESS.Additionally,it reviews the applications of causal inference in the main branches of the Earth system and summarizes the challenges and development directions of causal inference in ESS.In the big Earth data era,as an important method of big data analysis,causal inference,along with physical model and machine learning,can assist the paradigm transformation of ESS from a model-driven paradigm to a paradigm of integration of both mechanism and data.Looking forward,the establishment of a meticulously structured and normalized causal theory can act as a foundational cornerstone for fostering causal cognition in ESS and propel the leap from fragmented research towards a comprehensive understanding of the Earth system.

F4ESS-a framework for interdisciplinary data-driven earth system science

Earth system science is an interdisciplinary effort to understand the fundamentals and interactions of environmental processes.Interdisciplinary research is challenging since it demands the integration of scientific schemes and practices from different research fields into a collaborative work environment.This paper introduces the framework F4ESS that supports this integration.F4ESS provides methods and technologies that facilitate the development of integrative work environments for Earth system science.F4ESS enables scientists a)to outline structured and summarized descriptions of scientific procedures to facilitate communication and synthesis,b)to combine a large variety of distributed data analysis software into seamless data analysis chains and workflows,c)to visually combine and interactively explore the manifold spatiotemporal data and results to support understanding and knowledge creation.The F4ESS methods and technologies are generic and can be applied in various scientific fields.We discuss F4EsS in the context of the interdisciplinary investigation of flood events.

Harmonizing models and observations: Data assimilation in Earth system science

Models and observations are two fundamental methodological approaches in Earth system science(ESS). They evolve collaboratively and enhance one another. However, neither of these two approaches is perfect, and they have incompatibilities due to their methodological differences. The emergence of data assimilation(DA) has enabled these two approaches to develop in conjunction and form a harmonic ESS methodology. As a result, DA has shown a fresh vitality and applicability in ESS. This paper reviews the application of DA in the main branches of ESS, traces the coordinated evolution of DA with the methodologies of rationalism and empiricism, analyzes the relationships of DA with estimation theory and cybernetics, summarizes the advances of DA in China, and presents an outlook on the challenges facing the development of a uniform DA for ESS. DA theories and methods will continue to evolve and provide an increasingly mature methodology for enhancing the understanding and prediction of Earth as a system.

Understanding and building upon pioneering work of Nobel Prize in Physics 2021 laureates Syukuro Manabe and Klaus Hasselmann:From greenhouse effect to Earth system science and beyond

The Nobel Prize in Physics 2021 was awarded jointly to Syukuro Manabe,Klaus Hasselmann,and Giorgio Parisi for their groundbreaking contributions to our understanding of complex systems.This is the first time that climate scientists were awarded the Nobel Physics Prize.Here,we present the evolution of climate science in the past~200 years and highlight the landmarks of the developments in advancing our understanding of climate change,placing the pioneering contributions of Manabe and Hasselmann into a historical perspective.The backbone of modern climate science is further discussed in the context of the development of the discipline from the discovery of the greenhouse effect to the formation of Earth system science.Perspectives on the future development of climate science are also`presented.

Multisphere Tectonics of the Earth System

The fundamental theoretical framework of the Multisphere Tectonics of the Earth System is as follows:(1)It intends to extend the geotectonic studies from the crustal and lithospheric tectonics to the multisphere tectonics of the Ear th system as a whole.(2)The global dynamics driven by both the Earth system and the cosmic celestial system:solar energy,multispheric interactions of the Earth system and the combined effects of the motions of celestial bodies in the cosmos syste m are the driving forces of various geological processes.(3)The Continent-Ocean transformation theory:the continent and ocean are two opposite yet unified geological units,which can be transformed into each other;neither continent nor ocean wi ll survive forever;there is no one-way development of continental accretion or ocean extinction;the simple theory of one-way continental accretion is regarded as invalid.(4)The continental crust and mantle are characterized by multiple layers,with different layers liable to slide along the interfaces between them,but corroboration is needed that continents move as a who le or even drift freely.(5)The cyclic evolution theory:the development of Earth’s tectonics is not a uniform change,but a spiral forward evolution,characterized by a combination of non-uniform,non-linear,gradual and catastrophic changes;different evolutionary stages(tectonic cycles)of Earth have distinctive global tectonic patterns and characteristics,one tectonic mo del should not be applied to different tectonic cycles or evolutionary stages.(6)The structure and evolution of Earth are asymmetric and heterogeneous,thus one tectonic model cannot be applied to different areas of the world.(7)The polycyclic evolution of the continental crust:the continental crust is formed by polycyclic tectonics and magmatism,rather than simply lateral or vertical accretion.(8)The role of deep faults:the deep fault zones cutting through different layers of the crus t a nd mantle usually play important roles in tectonic evolution.For example,the present-day mid-ocean ridge fault zones,transform fault zones and Benioff zones outline the global tectonic framework.Different tectonic cycles and stages of Earth’s evolutio n must have their own distinctive deep fault systems which control the global tectonic framework and evolutionary processes during different tectonic cycles and stages.Starting from the two mantle superplumes Jason(Pacific)and Tuzo(Africa),the study of the evolutionary process of the composition and structure of the crust and mantle during the great transformation an d reorganization of the Meso-Cenozoic tectonic framework in China and the other regions of Asia is a good demonstration of theory of Multisphere Tectonics of the Earth System.

A view-based model of data-cube to support big earth data systems interoperability

Big Earth Data-Cube infrastructures are becoming more and more popular to provide Analysis Ready Data,especially for managing satellite time series.These infrastructures build on the concept of multidimensional data model(data hypercube)and are complex systems engaging different disciplines and expertise.For this reason,their interoperability capacity has become a challenge in the Global Change and Earth System science domains.To address this challenge,there is a pressing need in the community to reach a widely agreed definition of Data-Cube infrastructures and their key features.In this respect,a discussion has started recently about the definition of the possible facets characterizing a Data-Cube in the Earth Observation domain.This manuscript contributes to such debate by introducing a view-based model of Earth Data-Cube systems to design its infrastructural architecture and content schemas,with the final goal of enabling and facilitating interoperability.It introduces six modeling views,each of them is described according to:its main concerns,principal stakeholders,and possible patterns to be used.The manuscript considers the Business Intelligence experience with Data Warehouse and multidimensional“cubes”along with the more recent and analogous development in the Earth Observation domain,and puts forward a set of interoperability recommendations based on the modeling views.

Integrated research methods in watershed science

We discuss the concepts, research methods, and infrastructure of watershed science. A watershed is a basic unit and possesses all of the complexities of the land surface system, thereby making it the best unit for practicing Earth system science. Watershed science is an Earth system science practiced on a watershed scale, and it has developed rapidly over the previous two decades. The goal of watershed science is to understand and predict the behavior of complex watershed systems and support the sustainable development of watersheds. However, watershed science confronts the difficulties of understanding complex systems, achieving scale transformation, and simulating the co-evolution of the human-nature system. These difficulties are fundamentally methodological challenges. Therefore, we discuss the research methods of watershed science, which include the self-organized complex system method, the upscaling method dominated by statistical mechanics, Darwinian approaches based on selection and evolutionary principles, hydro-economic and eco-economic methods that emphasize the human-nature system co-evolution, and meta-synthesis for addressing unstructured problems. These approaches together can create a bridge between holism and reductionism and work as a group of operational methods to combine hard and soft integrations and capture all aspects of both natural and human systems. These methods will contribute to the maturation of watershed science and to a methodology that can be used throughout land-surface systems science.

Progress in watershed geography in the Yangtze River Basin and the affiliated ecological security perspective in the past 20 years,China

Bibliometrics was used to statistically analyze key zones within the Yangtze River Basin(YRB)funded by the National Natural Science Foundation of China(NSFC)and national ministries over the past 20 years.This study determined that funds that derived from national ministries have mainly focused on issues related to environmental pollution,ecological security,technological water regulations,and river basin ecosystems,which offer a better understanding of the national requirements and the scientific knowledge of the YRB in combination with data from the NSFC.Under a background of bolstering the construction of green ecological corridors in the economic belt of the YRB,this study proposes future conceptual watershed research initiatives in this region as a study objective by reinforcing the implementation of the Chinese Ecosystem Research Network(CERN)and by emphasizing the use of new technologies,new methods,and new concepts for the prospective design of frontier research under the perspective of geoscience and earth system science.This study promotes large-scale scientific field and research objectives based on big science and big data.

INTRODUCING A NEW INTERNATIONAL PROGRAM:MONSOON ASIA INTEGRATED REGIONAL STUDY (MAIRS)

The Monsoon Asia Integrated Regional Study （MAIRS） is a new Earth System Science Partnership （ESSP） program aimed at the integrated study of environmental changes over monsoon Asian region. This paper briefly introduces MAIRS, its background and concept, scientific themes and objectives, data requirements and its information system, intensive observation experiment, and its linkage with ongoing international projects.