Climate Change, Geology, and Ecosystems Practice Flashcards

Comprehensive vocabulary flashcards covering climate change evidence, geological processes, Earth's interior, fluvial and glacial systems, and ecosystem fundamentals based on Lecture 8-13 notes.

Climate

The long-term average of weather conditions and extremes in a specific region.

Climate change

Changes in the state of the climate through its mean or variability on seasonal, decadal, or longer temporal scales.

Global warming

A rise in global temperature specifically due to the increase in greenhouse gases.

Arctic amplification

A phenomenon where the Arctic warms at more than twice the global average rate, mostly in winter, weakening the jet stream and destabilizing the polar vortex.

Convection (Arctic Context)

The process where hot air rises and mixes vertically; in the Arctic, the absence of this causes greenhouse gas warming to be larger near the surface.

Ocean warming

The absorption of $90\%$ of global warming by the ocean, resulting in a temperature increase of $0.4\,^{\circ}C$ over 30 years.

Ice cores

Long-term climate reconstruction method reaching back 800,000 years, using air bubbles for atmospheric composition and oxygen isotope ratios for temperature.

Oxygen isotope ratios

The ratio of heavy to light oxygen isotopes used to suggest ancient temperatures; fewer heavy isotopes in polar ice cores indicate lower ancient temperatures.

Radiocarbon dating

A short-term climate reconstruction method using the constant decay rate of $^{14}C$, which has a half-life of $5,730$ years.

Tree rings

The study of annual growth rings where wider rings indicate favorable conditions and narrow rings indicate harsher conditions, going back 10,000 years.

Paleocene-Eocene Thermal Maximum (PETM)

A period 50 million years ago characterized by a sudden increase in $CO_2$ and a significant spike in temperatures.

Solar constant

The Sun's luminosity, which has increased by $30\%$ since its creation, growing at a rate of approximately $1\%$ every 110 million years.

Milankovitch Cycles

Natural cycles in Earth's orbit including the 100,000-year elliptical cycle and the 41,000-year axial tilt cycle ($21.5$ to $24.5$ degrees).

Albedo

A measure of surface reflectivity from 0 to 1; for example, the open ocean is $<0.1$, ice is $0.5$, and snow is $0.9$.

Cryosphere

A dynamic system encompassing all places on Earth where water exists in a solid form.

Sea Ice

Frozen ocean water that serves as a reflective barrier and habitat; its summer extent is shrinking by $12.6\%$ per decade.

Ice Sheets

Masses of glacial land ice extending more than $50,000\,km^2$, such as those in Greenland and Antarctica which contain $77\%$ of Earth's freshwater.

Mass balance (Glacial)

The net gain or loss of ice calculated as the difference between accumulation (snowfall, avalanches) and ablation (melting, sublimation, calving).

Ocean acidification

The reduction in ocean pH caused by the uptake of $30\%$ of atmospheric $CO_2$, resulting in fewer carbonate ions for calcifying organisms.

Keeling curve

A graph showing the seasonal variations and the long-term increase of atmospheric $CO_2$ levels, which have raised $50\%$ in less than 200 years.

REDD+

A program focused on reducing emissions from deforestation and forest degradation in developing countries.

Geoengineering

Large, planetary-scale interventions in the Earth's atmosphere, oceans, and land designed to counteract climate change.

Endogenic system

Internal Earth processes powered by radioactive decay and primordial heat, such as tectonics, earthquakes, and volcanoes.

Exogenic system

External Earth processes powered by solar energy and gravity, such as weathering, erosion, and the action of rivers and glaciers.

Earth's Core

The hottest part of the interior; the inner core is solid iron at $6000\,^{\circ}C$ due to pressure, and the outer core is molten liquid iron and nickel.

Lithosphere

The rigid, cooler outermost layer of Earth (up to $200\,km$) consisting of the crust and the uppermost mantle.

Asthenosphere

A plastic, semi-fluid layer in the upper mantle ($70\,km$ to $250\,km$) that is $10\%$ molten, allowing tectonic plates to move.

Igneous rock

Rock formed from cooling magma or lava; intrusive types cool slowly below the surface, while extrusive types cool quickly on the surface.

Sedimentary rock

Rock formed from the compaction, cementation, or chemical precipitation of minerals and organic remains, representing $75\%$ of surface rocks.

Metamorphic rock

Rock that has been changed by heat and pressure, occurring through contact with magma (contact) or deep in the lithosphere (regional).

Seafloor Spreading

The process where magma rises from diverging plates to create new ocean crust, driving continental movement.

Subduction

A process at a convergent boundary where one tectonic plate is pushed under another into the mantle.

Orogeny

A term meaning 'mountain generating,' referring to the process of mountain building through plate collisions.

Anticline

An arch-shaped upward fold in rock strata caused by crustal deformation.

Syncline

A trough-shaped downward fold in rock strata caused by crustal deformation.

Epicenter

The area on the Earth's surface directly above the focus, where an earthquake's seismic waves are initiated.

Richter scale

A logarithmic scale that calculates earthquake size by measuring ground motion on a seismograph.

Shield volcano

A broad volcano formed from effusive, low-viscosity eruptions, typically associated with hotspots and continental rift zones.

Drainage Basin

Also known as a watershed, it is the area of landscape from which a particular river or stream receives its water.

Stream discharge

The volume of flow per unit of time, calculated using the formula $Q = w \times d \times v$.

Competence

A stream's ability to move particles of a specific size.

Capacity (Fluvial)

The total sediment load a stream can transport, which is a function of its discharge.

Aggradation

The build-up of a river channel through deposition when energy and capacity are reduced.

Nickpoint

A point of interruption in a stream's gradient, such as a waterfall or rapids, where erosive action undercuts the bank.

Spring tides

Tides with the greatest tidal range, occurring during the full moon and new moon.

Neap tides

Tides with a lesser tidal range, occurring during quarter moons.

Aeolian

Pertaining to wind processes, including the erosion (deflation/abrasion), transport, and deposition of materials.

Glacier

A large mass of ice resting on land or floating as an ice shelf, moving slowly in stream-like patterns following valleys.

Firn

An intermediate stage in the formation of glacial ice where old snow is compressed and re-crystallized.

Moraine

A landform produced by the deposition of glacial sediment (till); types include terminal, lateral, medial, and ground moraines.

Permafrost

Soil or rock that remains below $0\,^{\circ}C$ for at least two consecutive years.

Net Primary Production (NPP)

The initial conversion of $CO_2$ into plant biomass, representing the difference between GPP and carbon lost through respiration.

Nitrogen fixation

The process where mid-soil and root bacteria convert atmospheric nitrogen ($78\%$ of air) into ammonia.

Trophic cascade

An ecological phenomenon triggered by the addition or removal of top predators, leading to reciprocal changes in predator and prey populations.

Endemism

The state of a species being native and exclusive to a single specific geographical area.

Fundamental niche

The complete set of environmental conditions and resources an organism can theoretically survive in without limiting factors from other species.

Realized niche

The actual set of conditions and resources an organism uses, restricted by biotic interactions like competition and predation.

Climate Velocity (CV)

A measure calculated as $CV = \text{climate change [degree/y]} / \text{climate gradient [degree/km]}$.