GEOG 1020: Quiz #4

Space weather

Environmental changes in space driven by the Sun, specifically solar flares, radiation storms, and coronal mass ejections (CMEs)

Solar cycle

An approximately 11-year period of fluctuations in the Sun's magnetic field and activity, marked by changes in the number of sunspots; it begins at a solar minimum (few sunspots) and moves to a solar maximum (maximum sunspots and intense activity), during which the Sun's magnetic poles reverse

Solar flares

Bursts of electromagnetic radiation that reach Earth in about eight minutes and can trigger radio blackouts and communication interruptions

Coronal mass ejections (CMEs)

Large expulsions of plasma and magnetic field from the Sun’s corona that can cause geomagnetic storms, power fluctuations, and transformer impacts

Radiation storms

Occur when large bursts of charged particles—primarily protons—are emitted by the Sun during solar flares or coronal mass ejections, affecting spacecraft electronics, astronauts, and high-frequency radio near the poles

Geomagnetic storm

A major, temporary disturbance of Earth’s magnetosphere caused by solar wind shockwaves or coronal mass ejections (CMEs) interacting with our planet's magnetic field

Carrington Event (1859)

The most powerful geomagnetic storm in recorded history when a massive solar coronal mass ejection (CME) struck Earth, causing global telegraph system failures, widespread electrical sparks, and auroras visible as far south as the Caribbean

Hydrologic (water) cycle

The continuous, solar-driven movement of water between the Earth's surface, atmosphere, and subsurface, with key stages include evaporation/transpiration, condensation, precipitation, and runoff/infiltration, constantly recycling freshwater

Evaporation

The physical process where a liquid turns into a gas (vapor), driven by heat energy

Transpiration

The process where water evaporates from plants, moving from the soil through the plant into the atmosphere

Evapotranspiration

The combined process of water transferring from the Earth's surface to the atmosphere through evaporation and transpiration, accounting for 14% of the water entering Earth’s atmosphere

Percolation

The slow, gradual movement of a liquid through a porous substance or filter, commonly used to describe water seeping through soil

Soil moisture zone

The top layer of soil, typically extending from the surface down to roughly 1 meter, from which plants extract water and nutrients

Soil moisture storage

The volume of water held within the soil pore spaces, generally located between the land surface and the groundwater table

Water budget

An accounting system that tracks the rates of water inflows, outflows, and changes in storage within a specific area or watershed over a set time, based on the principle of conservation of mass

Precipitation

The process where water—in liquid or solid forms like rain, snow, sleet, or hail—falls from clouds in the atmosphere back to the Earth's surface

Actual evapotranspiration

The water that is actually moving from the land to the atmosphere

Potential evapotranspiration

The water that could move to the atmosphere if enough moisture were available

Runoff

The precipitation water that does not infiltrate into the soil

Maximum storage

Determined by the total porosity of the soil, which will be almost the same as the saturated water content

Wetlands

An area of land that is either covered by shallow water or has waterlogged soil for at least part of the year

Groundwater

Water found underground in the cracks and spaces of soil, sand, and rock, storing in geological formations called aquifers

Water table

The upper, underground boundary where the soil or rock becomes completely saturated with water

Aquifer

A scientifically defined body of saturated, permeable rock, sand, gravel, or fractured limestone located underground, capable of storing and transmitting usable amounts of groundwater

Climate

The collective pattern of weather over many years, long-term average atmospheric conditions

Climatology

The study of climate and its variability

Köppen-Geiger Climate Classification

A widely used system for categorizing world climates based on annual and monthly averages of temperature and precipitation, designed to match vegetation zones

Six basic climate categories

1. Tropical — (tropical latitudes)

2. Mesothermal — (midlatitudes, mild winter)

3. Microthermal — (mid and high latitudes, cold winters)

4. Polar — (high latitudes and polar regions)

5. Highland — (high elevations at all latitudes; highlands have lower temperatures)

6. Dry — (permanent moisture deficits)

Isotopes

Variants of elements with the same number of protons but different neutron counts, resulting in distinct atomic masses

Ice cores

Cylinder-shaped samples drilled from glaciers and ice sheets that act as "time machines" for climate science

Milankovitch cycles

Periodic variations in Earth’s orbit, axial tilt, and wobble that influence the amount of solar radiation (insolation) reaching the Earth, driving long-term climate changes like ice ages over tens to hundreds of thousands of years

Palynology

The scientific study of organic microfossils—specifically pollen, spores, and plankton—to reconstruct past environments, date rock layers, and aid forensic investigations

Exine

The outer wall of a pollen grain

Intine

A more delicate inner wall made mostly of cellulose and pectin

Apertures

Where the exine is thinner or absent, emerging during fertilization or periods of vulnerability

Conditions leading to pollen degradation

1. Extremely harsh chemical environments

2. Biological degradation

3. Physical abrasion and weathering

4. Ultraviolet (UV) radiation

Macrofossils

Fossilized remains of plants, animals, or trace evidence large enough to be observed and studied without a microscope

Microfossils

Microscopic remains of organisms—typically algae, protists, or small invertebrates—preserved in sedimentary rock, usually requiring electron or light microscopes to identify

Precambrian era

The earliest and longest unit of geologic time, spanning from Earth's formation about 4.6 billion years ago to roughly 538.8 million years ago, representing nearly 90% of Earth's history during which the planet cooled, oceans formed, and early life evolved

Paleozoic era

The first and longest era of the Phanerozoic Eon, marked by a massive explosion of complex life, the colonization of land by plants and animals, and the assembly of the supercontinent Pangaea

Mesozoic era

The "Age of Reptiles" or "Middle Life,", featuring the dominance of dinosaurs, the breakup of the supercontinent Pangea, and a warm climate, ending with a mass extinction event caused by an asteroid

Cenozoic era

The current and most recent geological era, spanning from 66 million years ago to the present, defined by the rapid diversification of mammals, birds, and flowering plants following the dinosaur extinction, along with significant global cooling, the rise of major mountain ranges, and the evolution of humans

Medieval Climate Anomaly (MCA)

A time of unusual regional climate variability from around 950 to 1250 CE, characterized by warmer, often drier conditions in the North Atlantic and Europe, and significant fluctuations elsewhere

Little Ice Age

A period of regional cooling, primarily in the North Atlantic and Europe, lasting roughly from 1300 to 1850, marked by advancing glaciers, harsh winters, and wet summers, resulting in crop failures, famine, and significant socio-political disruptions

Anthropocene

A proposed, current geological epoch defined by humanity's significant, accelerating impact on Earth's ecosystems, geology, and climate

Factors of natural climate fluctuation

1. Solar variability

2. Earth’s orbital cycles

3. Continental position and topography

4. Atmospheric gases and aerosols

Climate feedbacks

Natural processes within the Earth system that respond to, and either amplify (positive) or diminish (negative) an initial change in global climate, such as temperature increases

Carbon budget

The maximum amount of cumulative, global net CO₂ emissions allowed to keep global warming within a specific limit, such as 1.5°C or 2°C above pre-industrial levels

Global climate models

Used to assess past climatic trends and forecast future climate changes

Pros of the IPCC projection

• Multi-model ensembles

• Scenario-based projections (SSPs)

• Process-based Earth system simulations

Cons of the IPCC projection

• Cloud feedback

• Regional-scale prediction is weak

• Structural model bias (emphasize on macro-factors)

Solar and wind expansion

• Replace fossil fuel electricity with near-zero GHG sources

• Driven by cost declines + grid-scale deployment

• Backbone of most IPCC mitigation pathways

Electrification of end uses

• Shift transport, heating, cooking → electricity

• Major sectors: EVs, heat pumps, electric industry

• Enables decarbonization

Carbon capture and engineered removal

• Captures CO₂ at point sources (power plants, cement, steel)

• Injects into deep geological formations

• Key for “hard-to-abate” sectors (e.g., steel, cement, shipping, and aviation; ~40% of global emissions)

Direct air capture

• Removes CO₂ directly from atmosphere

• Currently expensive and energy-intensive

• Important for achieving net-negative emissions

Reforestation and afforestation

• Trees store carbon in biomass + soils

• Relatively low-cost, scalable

• Limited by land availability & permanence risks (fire, drought)

Coastal “blue carbon” ecosystems

• Mangroves, salt marshes, seagrass trap and bury carbon in sediments

• High long-term storage efficiency (anoxic burial)

• Directly aligned with wetland & paleoecology work