Skip to Content


The mechanism through which energy (e.g., solar or infrared) is converted into heat and contributes to the overall warming of the Earth's atmosphere and surface.
adaptive radar scanning
Adaptive radar (weather) scanning consists of changing the radar’s scanning strategy in response to changes in the atmosphere.
aerosol-cloud interaction
The interaction of airborne particles (aerosols) with clouds. Scientists study how aerosols affect clouds and how these interactions can impact the Earth's climate.
Small particles or droplets, such as wildfire smoke, volcanic gases, or salty sea spray, that float in the air. They are emitted by both natural events and human activities.
anthropogenic aerosol
Tiny particles suspended in the atmosphere that are primarily generated by human activities.
Having to do with water.
ARM data
Continuous field measurements of atmospheric data collected with Atmospheric Radiation Measurement (ARM) instruments at fixed and varying locations worldwide.
artificial intelligence
A machine-based system that can, for a given set of human-defined objectives, make predictions, recommendations or decisions influencing real or virtual environments.
Atlantic Meridional Overturning Circulation
The Atlantic Meridional Overturning Circulation (AMOC) circulates water from north to south and back in a long cycle within the Atlantic Ocean. This circulation brings warmth to various parts of the globe and also carries nutrients necessary to sustain ocean life.
atmospheric aging
Refers to the gradual alteration of atmospheric constituents, including gases and aerosols, through chemical, physical, and biological processes over time.
atmospheric radiative transfer
The science of understanding how electromagnetic radiation emitted by both the Sun and Earth interacts with the gases, clouds and particles making up our atmosphere.
atmospheric river
Long, narrow regions in the atmosphere – like rivers in the sky – that transport most of the water vapor outside of the tropics.
atom probe tomography
A unique analytical tool capable of providing 3D atomic maps of any element in the periodic table with sub-nm (sub-nanometre) spatial resolution and high analytical sensitivity (in the ppm range, in some cases).
biochemical process
The interaction of organisms with their abiotic (non-living part of an ecosystem) environment and other organisms by chemical means
Economic activity derived from the life sciences, particularly in the areas of biotechnology and biomanufacturing, and includes industries, products, services, and the workforce.
A renewable energy derived from biological sources, to be used for heat, electricity, or vehicle fuel.
Liquid fuels that are produced from renewable biological sources, including plants and algae. Biofuels offer an alternative to some of the challenges of solar, wind, and other alternative energy sources.
biogeochemical processes
The complex interactions and transformations of chemical elements and compounds that occur throughout Earth's ecosystems, such as nutrient and element cycling between living organisms, the atmosphere, hydrosphere, lithosphere, and pedosphere (soil).
Studies the cycle of key elements like carbon, nitrogen, and phosphorus within Earth's systems. It explores how these elements interact and the factors influencing their cycles.
A biological molecule found in blood, other body fluids or tissues that is a sign of a normal or abnormal process, or of a condition or disease.
Material that comes from living things, including trees, crops, grasses, and animals and animal waste. Some kinds of biomass, such as wood and biofuels, can be burned to produce energy.
A device that measures biological or chemical reactions by generating signals proportional to the concentration of an analyte in the reaction.
black carbon
The sooty black material emitted from gas and diesel engines, coal-fired power plants, and other sources that burn fossil fuel. It comprises a significant portion of particulate matter or PM, which is an air pollutant.
Boreal forests (sometimes called "taiga") are a mosaic of forest types — from sunny aspen groves to spruce bogs-intermingled with meadows, marshes, lakes, and rivers — in the northern high latitude regions. This ecosystem is characterized by cold weather, long winters, and permafrost.
carbon cycle
The movement and exchange of carbon through living organisms, the ocean, the atmosphere, rocks and minerals, and other parts of the Earth.
carbon dioxide (CO2)
An important heat-trapping gas, also known as a greenhouse gas, that comes from the extraction and burning of fossil fuels (such as coal, oil, and natural gas), from wildfires, and natural processes like volcanic eruptions.
carbonaceous aerosol (CAA)
Carbonaceous aerosols (particles) in the atmosphere scatte and absorb solar radiation. They comprise of both light-absorbing (elemental carbon and brown carbon) and scattering (organic carbon) species. The absorbing fraction is called black carbon and is primarily produced from incomplete combustion.
Defined as the application of mathematical and statistical methods to chemistry.
A computationally efficient model for simulating the growth, melting, and movement of polar sea ice.
cirrus clouds
Detached clouds in the form of white, delicate filaments, mostly in patches or narrow bands. They may have a fibrous (hair-like) and/or silky sheen appearance.
climate change
A change in the average conditions — such as temperature and rainfall — in a region over a long period of time.
climate extreme
Significant deviations or anomalies from typical weather patterns and conditions, observed over extended periods such as seasons or even longer durations.
climate feedback
Processes that can either amplify or reduce the effects of climate drivers (e.g., solar radiation; greenhouse gas emissions; and aerosols, dust, smoke, and soot). A feedback that increases an initial warming is called a "positive feedback." A feedback that reduces an initial warming and then returns the system to it's original state is a "negative feedback."
cloud chemistry
The study of the chemical makeup, reactions, and phenomena that take place inside clouds.
cloud condensation nuclei
Tiny airborne particles suspended in the atmosphere that serve as the seeds around which cloud droplets form.
cloud dynamics
The processes and behaviors that occur during the formation, development, movement, and dissipation of clouds in the Earth's atmosphere.
cloud electrification
The process by which clouds are electrically charged.
Atmospheric aerosols generally have a two modes. The smaller particles are referred to as the fine mode or accumulation mode aerosols. The larger particles comprise the coarse mode. These particles generally have radii between 1.0 and 2.5 microns.
coastal ecosystem
Coastal habitats include estuaries, wetlands and marshes, coral reefs, kelp forests, tidepools, and barrier islands.
compound flooding
When two or more flood drivers (e.g. rainfall, storm surge) occur simultaneously or in close succession. A coastal compound-flood event occurs when floods caused by storm surge and rising tides combine with inland flooding from heavy rainfall.
computational modeling
The use of computers to simulate and study complex systems using mathematics, physics, and computer science.
The rising of warm air and the sinking of cool air. Convection can cause local breezes, winds, and thunderstorms.
The study of the origin, development, structure, history, and future of the entire universe.
The frozen water part of the Earth system. This includes frozen parts of the ocean, such as waters surrounding Antarctica and the Arctic.
data reduction
Data reduction involves techniques such as simplifying large sets of complex climate data into more manageable and meaningful information. 
Decarbonization involves the reduction or eradication of carbon dioxide emissions from specific systems, such as industries, economies, or societies.
deep convective cloud
Deep convective clouds (e.g., cumulonimbus clouds) are associated with severe storms, which can transport ice and supercooled large droplets into the higher levels of the atmosphere, frequently reaching an altitude of 10 km (33,000 feet), and sometimes much higher.
Where rivers discharge a large quantity of sediment directly into the ocean. These deposits commonly assume a triangular shapes and are termed deltas because they resemble the Greek capital letter delta (Δ).
digital thread
A digital thread refers to the interconnected data flow that follows a product or process throughout its lifecycle, from design and development through manufacturing, distribution, and maintenance.
digital twin
A set of virtual information constructs that mimics the structure, context, and behavior of a natural, engineered, or social system (or system-of-systems); is dynamically updated with data from its physical twin; has a predictive capability; and informs decisions that realize value.
dissolved oxygen
The amount of oxygen that is present in water. Water bodies receive oxygen from the atmosphere, runoff, and from aquatic plants.
earth system model (ESM)
A model that simulates how chemistry, biology, and physical forces work together. These models are similar to, but much more comprehensive than, global climate models.
The interrelationships between living organisms and their environments.
A natural community of plants, animals, and other living organisms and the physical environment in which they live and interact.
ecosystem modeling
A mathematical representation of an ecological system that can range in scale from an individual population, to an ecological community, or even an entire biome.
A discipline of chemistry concerned with the interconversion of electrical and chemical energy.
Energy Exascale Earth System Model (E3SM)
The Energy Exascale Earth System Model (E3SM) project includes Earth System Models, simulations, and predictions to investigate energy-relevant science using code optimized for DOE's advanced supercomputers.
The geological process in which Earth's materials are worn away by weathering processes and transported away by natural forces such as wind or water.
A partially enclosed, coastal water body where freshwater from rivers and streams mixes with salt water from the ocean.
A renewable fuel made from corn and other plant materials.
The process by which water moves from the land or ocean surface to the atmosphere (evaporation) and transpiration (evaporation from plants).
The nearly flat portion of a river valley built by sediment deposited during previous floods.
The amount of some type of particle or energy crossing a unit area per unit time.
fusion energy
A multi-disciplinary field focused on the science needed to develop an energy source based on a controlled thermonuclear fusion reaction.
generative AI
Generative artificial intelligence (AI) is a technology that can create content, including text, images, audio, or video, when prompted by a user.
An interdisciplinary field of science that focuses on the structure, function, evolution, mapping, and editing of genomes.
geochemical reduction/oxidation (redox)
Redox processes require one chemical species that donates electrons and another chemical species that accepts those electrons. As a chemical species donates electrons it is “oxidized,” and as the other species accepts electrons it is “reduced.”
geochemical stabilization
A process which stabilizes the amount, distribution, or structure of chemical elements in air, water, soil, rocks, and minerals.
Heat energy from the earth—Geo (earth) + thermal (heat).
global climate model (GCM)
A complex mathematical representation of the major climate system components (atmosphere, land surface, ocean, and sea ice), and their interactions.
global storm resolving model (GSRM)
Global storm resolving models (GSRMs), which have ultra-high horizontal resolutions (e.g., 1-5 km) are capable of simulating convective storms directly, for extended time frames (e.g., greater than one month).
Water that occurs below Earth's surface. When rain falls to the ground, a portion percolates (sinks) into the ground and collects in spaces in the underground rocks.
heat island
Structures such as buildings, roads, and other infrastructure absorb and re-emit the sun’s heat more than natural landscapes such as forests and water bodies. Urban areas, where these structures are highly concentrated and greenery is limited, become “islands” of higher temperatures relative to outlying areas.
high-performance computing (HPC)
High-performance computing – the most powerful and largest scale computing systems – enables researchers to study systems that would otherwise be impractical, or impossible, to investigate in the real world due to their complexity or the danger they pose
hydro-biogeochemical process
The coupled hydrological, geochemical, and biological processes that control water quality.
hydrodynamic process
The movement and behavior of fluids, notably water, as influenced by various forces such as gravity, pressure gradients, and fluid viscosity.
hydrogen fuel
A clean fuel that, when consumed in a fuel cell, produces only water. Hydrogen can be produced from a variety of domestic resources, such as natural gas, nuclear power, biomass, and renewable power like solar and wind.
hydrological processes
Hydrological processes refer to the various natural processes involved in the movement, distribution, and cycling of water on Earth's surface, in the soil, and within the atmosphere.
The science that deals with water, its properties, circulation, or distribution on Earth's surface, and in the atmosphere through evapotranspiration.
ice nucleating particles
Tiny specks of material suspended in the air that act as starting points for the formation of ice crystals in clouds.
ice-nucleating particles
Tiny specks of material suspended in the air that act as starting points for the formation of ice crystals in clouds.
infrared (IR) spectroscopy
Infrared (IR) spectroscopy deals with the infrared region of the electromagnetic spectrum. IR wavelengths are longer, with a lower frequency than visible light. IR can be used to identify and study chemicals.
Inundation is the flooding of land that is normally dry. It can be caused by a variety of factors, including heavy rain, snowmelt, or a storm surge. Inundations can be a major hazard, causing damage to property and infrastructure, and even loss of life.
The controlled application of water for agricultural purposes through manmade systems to supply water requirements not satisfied by rainfall.
large language models (LLMs)
Advanced artificial intelligence systems designed to understand and generate human-like text based on the input they receive.
One of the main components of plant cell wall and it is a natural phenolic polymer with high molecular weight, complex composition and structure.
machine learning (ML)
Machine Learning (ML) refers to the field and practice of using algorithms that are able to “learn” by extracting patterns from a large body of data.
marginal soil
Soils that are rocky, sandy, or shallow with a limited reservoir of nutrients and water and are unsuited for food crops.
mass spectrometry (MS)
Mass spectrometry (MS) is an analytical technique that separates ionized particles such as atoms, molecules, and clusters and can be used to determine the molecular weight of the particles.
mesoscale convective system (MCS)
A collection of thunderstorms that act as a system. An MCS can spread across an entire state and may appear as a solid line, a broken line, or a cluster of cells that can last more than 12 hours.
metabolic reconstruction
Metabolic reconstruction involves determining the set of reactions required for utilizing nutrients to synthesize and break down basic metabolites and complex compounds.
A collection of genomes from many individuals within an environment and/or sample.
A hydrocarbon that is a primary component of natural gas. Methane is also a greenhouse gas (GHG), so its presence in the atmosphere affects the earth’s temperature and climate system
Microbes are tiny living things that are found all around us and are too small to be seen by the naked eye. They live in water, soil, and in the air.
microbial ecology
Studies the relationships of germs across many settings, including the diversity and abundance of germs within microbiomes.
microbial response
Occurs when a microorganism develops a series of strategies to resist environmental stresses.
Microbiology is the study of microorganisms that are usually too small to be visible with the human eye without a microscope. These tiny organisms shape how nutrients move through the environment.
The local climate of a small site or habitat.The climate of a small area such as a cave, house, city or valley that may be different from that in the general region.
The use of microscopes to view samples and objects that cannot be seen with the unaided eye.
minority Serving Institution (MSI)
A term used to describe colleges and universities that primarily enroll and serve minority populations. These groups can include African Americans, Hispanics, American Indians, Alaska Natives, Native Hawaiians, and Asian Americans.
The science of the form and structure of organisms (plants, animals, and other forms of life).
multisector dynamics
Multisector dynamics aims to enhance our knowledge of the intricate interactions, interconnections, and mutually influential paths between human and natural systems.
Classified as a nonmetal, nitrogen is a gas at room temperature. Nitrogen dilutes oxygen and prevents rapid burning at the Earth's surface, and accounts for ~78 percent of Earth's atmosphere.
nutrient cycle
The nutrient cycle describes how nutrients move from the physical environment into living organisms and are recycled back to the physical environment.
A chemical reaction that takes place when a substance comes into contact with oxygen or another oxidizing substance. One example of oxidation is rusting of iron when the iron interacts with oxygen and water. In climate science, oxidation is important because it is one of the processes that leads to the formation of greenhouse gases.
Located within a terrestrial wetland environment where plant material cannot entirely decompose due to the presence of water.
Any ground that remains completely frozen—32°F (0°C) or colder—for at least two years straight. These permanently frozen grounds are commonly found in regions with high mountains and near the North and South Poles.
A petabyte is equal to one quadrillion (one thousand trillion) bytes, 1 million gigabytes, or 1,000 TB.
Supercomputing capable of performing at least 1 FLOPS (floating-point operations per second) or storage systems capable of storing at least 1 petabyte. A petabyte is equal to one quadrillion (one thousand trillion) bytes, or 1,000 TB.
More commonly known as solar panels – generate power using devices that absorb energy from sunlight and convert it into electrical energy through semiconducting materials.
Relating to both physical and chemical properties of any sample or substance and their interactions and reactions.
planetary boundary layer
The lowest layer of the troposphere where wind is influenced by friction.
predictive understanding
Predictive understanding refers to the ability of a system, typically an artificial intelligence or machine learning model, to anticipate future events or outcomes based on historical data and patterns.
Pyrite (FeS2) is a mineral composed of the elements iron and sulfur.
pyrogenic organic matter (PyOM)
Pyrogenic organic matter (PyOM) is produced by the incomplete combustion of organic matter. PyOM can represent a large portion of total soil organic carbon in fire-affected systems, and where PyOM is added intentionally as a soil amendment.
Python is a programming language that is an interpreted, object-oriented, high-level language used to automate tasks and conduct data analysis.
Data represented numerically, including anything that can be counted, measured, or given a numerical value.
quantum error mitigation
Refers to techniques used to reduce or correct errors that occur in quantum computing systems due to factors such as noise, imperfect operations, and environmental interference.
quantum mechanic
The field of physics that explains how extremely small objects simultaneously have the characteristics of both particles (tiny pieces of matter) and waves (a disturbance or variation that transfers energy).
radar meteorology
Weather information based upon the returned burst of energy emited by the radar. Radiowaves strike an object (rain drop, snowflake, hail, bug, etc.) and return a small fraction of energy directly back toward the radar.
radiative balance
Radiation Balance is the energy balance between incoming energy from the Sun and outgoing energy from the Earth.
radiative flux
The measurement of the amount of radiant energy that is released from the Earth's atmosphere across specific wavelengths ranging from solar to thermal infrared.
A chemical reaction that takes place between an oxidizing substance and a reducing substance. The oxidizing substance loses electrons in the reaction, and the reducing substance gains electrons.
remote sensing
The process of detecting and monitoring the physical characteristics of an area by measuring its reflected and emitted radiation at a distance (typically from satellite or aircraft).
renewable energy
Renewable energy comes from unlimited, naturally replenished resources, such as the sun, tides, and wind. Renewable energy can be used for electricity generation, space and water heating and cooling, and transportation.
A manmade lake that is created when a dam is built on a river. River water backs up behind the dam creating a reservoir.
The process whereby living organisms consume CO2, convert it to energy, and release it as O2.
The soil region influenced by plant roots where complex biological and ecological processes occur.
river corridor
A river (or stream) corridor includes the width of the channel in which water flows and is typically expanded to account for the extensive influence of the watercourse into the surrounding landscape.
The measure of dissolved salts in water. The rise in sea level due to global warming could result in increased salinity of rivers, bays, and aquifers.
A genus of large brown seaweed (a type of algae) that floats in island-like masses and never attaches to the seafloor.
secondary metabolite
Those molecules produced by organisms that are not required for growth per se, but which provide significant advantages to those organisms producing them.
secondary organic aerosol (SOA)
Secondary Organic Aerosols (SOAs) are air pollutants emitted from natural and man-made sources. They are produced through a complex interaction of sunlight, volatile organic compounds from trees, plants, cars or industrial emissions, and other airborne chemicals.
A way of describing groups based on their education, income, or job type. Socioeconomic status is usually described as low, medium, and high.
soil carbon
The measurable amount carbon dioxide stored in soil. It is the primary indicator of soil health, and it impacts the chemical, physical, and biological characteristics of the soil.
soil carbon process
A cycle that moves carbon between plants, animals, and microbes, minerals in the earth, and in the atmosphere.
An instrument attached to a weather balloon that measures and transmits pressure, humidity, temperature, and winds as it ascends.
A cereal grain crop grown primarily for its seeds, which can be consumed by humans, fed to livestock, or used to make sorghum syrup.
Rainwater or melted snow that runs off streets, lawns and other sites.
Stratification refers to layers in rocks, soil, large bodies of water, and the atmosphere.
stratocumulus clouds
Low clouds with irregular masses of clouds, rolling or puffy in appearance, sometimes with space between the clouds.
surface water
Any body of water above ground, including streams, rivers, and lakes.
synchrotron radiation
The electromagnetic radiation emitted when charged particles travel in curved paths.
The process of combining a number of things into a coherent whole to form a theory or system.
The geographical and biological features that are associated with the Earth's solid, rocky surface, residing on or resembling the land or terrain found on our planet.
A process or phenomenon that involves both thermal (heat) and chemical reactions.
The land's physical attributes within a specific area or region, comprising both natural formations like mountains, valleys, and rivers, alongside human-made additions such as roads and buildings.
A type of ecosystem dominated by lichens, mosses, grasses, and woody plants. Generally located at high latitudes (arctic tundra) and high altitudes (alpine tundra).
Concentrations of human populations into discrete areas. This concentration leads to the transformation of land for residential, commercial, industrial and transportation purposes.
volatile organic compound (VOC)
Compounds that have a high vapor pressure and low water solubility. Many VOCs are human-made chemicals that are used and produced in the manufacture of paints, pharmaceuticals, and refrigerants.
water electrolysis
Defined as a chemical process in which water molecules (H2O) are divided into hydrogen gas (H2) and oxygen gas (O2) via an electric current.
An area of land that channels rainfall and snowmelt to creeks, streams, and rivers, and eventually flows to the lowest point in a basin.
An area of land that is periodically saturated with water, which influences the types of plants and animals that can live there. Wetlands include swamps, marshes, bogs, and other similar areas.