Global Circulation System
A complex pattern of atmospheric movements that distribute heat and moisture around the Earth, significantly influencing the planet's climate and weather patterns.
Hadley Cell
(Largest cell) the low-latitude overturning circulations that have air rising at the equator and air sinking at roughly 30° latitude.
Ferrel Cell
(Middle cells) its circulation are complicated by a return flow of air at high altitudes towards the tropics, where it joins sinking air from the Hadley cell.
Polar Cell
(Smallest and weakest cell) which extends from between 60 and 70 degrees north and south.
High Pressure
A condition of the atmosphere in which the pressure is above average.
Low Pressure
Characterized by or exhibiting atmospheric pressure that is below average.
Tropical Storms
Distribution: These storms thrive in warm ocean waters (typically above 26°C or 80°F) near the equator.
Frequency: The global number of tropical storms formed each year varies, but averages around 80-100.
Droughts
Distribution: Can occur anywhere globally.
Frequency: Can last weeks, months, or even years. Their frequency varies depending on the region's climate.
Causes of Extreme Weather Conditions Associated with Tropical Storm
Warm Ocean Temperatures
Low Atmospheric Pressure
Coriolis Effect
Minimal Wind Shear
Moisture Availability
Warm Ocean Temperatures
Fuels tropical storms as warm, moist air rises from the ocean surface, it cools and condenses, releasing energy that powers the storm.
Low Atmospheric Pressure
A key ingredient to tropical storms as air naturally flows from high pressure to low pressure.
Coriolis Effect
Deflects winds circulating in the storm system.
Minimal Wind Shear
Allows the storm to develop a more organized structure, concentrating its energy and strengthening it.
Moisture Availability
More available moisture adds more energy to release when it condense which fuels the storm intensity.
El Niño
The above-average sea-surface temperatures that periodically develop across the east-central equatorial Pacific.
Triggers: Shifted Jet Stream, Suppressed Convection, and Reduced Rainfall
La Niña
The periodic cooling of ocean surface temperatures in the central and east-central equatorial Pacific.
Triggers: Intensified Trade Winds, Altered Atmospheric Circulation, and Disrupted Precipitation Patterns
Layers of the Earth
Crust, Mantle, Inner Core, and Outer Core
Crust
The outermost, thin, solid layer (around 30-70 km thick). It is the earth’s skin with two main types;
Continental Crust
Thicker and less dense, made up mostly of granite and other rocks. (Continents)
Oceanic Crust
Thinner and denser, composed mainly of basalt. (Ocean Floors)
Mantle
The thickest layer, made up of hot, solid rock (about 2800 km thick).
Upper Mantle
More rigid due to cooler temperatures in which its solid portion, along with the crust, forms the lithosphere, which is broken into tectonic plates.
Outer Core
Liquid layer made of super hot molten iron and nickel (about 2200 km thick) where movement within this layer is crucial to plate tectonics.
Inner Core
Solid sphere of iron and nickel at the Earth's center (about 1200 km radius).
Plate Tectonics
A theory explaining the structure of the earth's crust and many associated phenomena as resulting from the interaction of rigid lithospheric plates which move slowly over the underlying mantle.
Convection Currents
A process that involves the movement of energy from one place to another
Earthquakes
Occurs when sudden movement or stress release happens along plate boundaries.
Shallow-Focus Earthquakes
The most common and destructive earthquakes where the movement of tectonic plates creates stress and strain on the rocks along plate boundaries.
Deep-Focus Earthquakes
Less frequent but can be powerful when the immense pressure and heat at these depths cause the rock to deform in a ductile (bendable) way, leading to sudden breaks and deeper earthquakes.
Volcanoes
Form at plate boundaries where molten rock (magma) from the mantle erupts onto the surface.
Shield Volcanoes
Broad, gently sloping volcanoes with a dome-like shape.
Composite Volcanoes
( or stratovolcanoes) are steep-sided, conical mountains with alternating layers of ash, lava, and rock debris that erupts with a more explosive style/
Mountain ranges
Created when plates collide and push against each other, forcing rock layers to buckle and rise.
Constructive Plate Boundaries (Divergent Boundaries)
Plates that diverge or pull away from each other.
Destructive Plate Boundaries (Convergent Boundaries)
One plate dives (subducts) beneath another.
Oceanic-Continental Convergence
Creates mountain ranges on the continent and volcanic arcs offshore.
Oceanic-Oceanic Convergence
Forms deep ocean trenches and volcanic island arcs.
Conservative Plate Boundaries (Transform Boundaries)
Plates that slide horizontally in opposite directions.
Collision Zone Boundaries
A special case of convergent boundaries occurs when two continental plates collide head-on.
Hotspots
Stationary plumes of hot molten rock rising from deep within the mantle, typically not located at plate boundaries.
Seismic-Resistant Construction
Advancements in engineering allow for buildings designed to withstand strong shaking.
Smart Building Materials
Emerging materials like self-healing concrete that can repair cracks or shape-memory alloys that return to their original form after deformation offer promising possibilities for earthquake-resistant infrastructure.
Earthquake Monitoring Networks
Densely distributed seismic sensor networks can detect subtle changes in ground movement that might precede earthquakes.
AI-Powered Prediction Models
Artificial intelligence can analyze vast amounts of seismic data to identify patterns and correlations that might lead to improved earthquake prediction capabilities.
Early Warning Systems for Public Alerts
Advanced communication technologies can be used to disseminate real-time earthquake alerts to the public via smartphones, loudspeakers, and other channels.
Pattern of Climate Change
Glacial Period, Interglacial Period, and the Current Interglacial
Glacial Periods (Ice Ages)
Lasted for much longer durations, typically tens of thousands of years where colder global temperatures prevailed with drier conditions in many regions.
Interglacial Periods
Relatively warm intervals lasting several thousand years where global temperatures were warmer, with increased precipitation and vegetation growth in many areas.
The Current Interglacial
known as the Holocene epoch, which began about 11,700 years ago.
High Reliability Evidence
Global Temperature Data and Ice Cores
Moderate Reliability Evidence
Sea Ice Positions
Paintings and Diaries
Sunspots and Solar Activity
Suggests that variations in sunspot activity might influence Earth's climate.
Volcanic Eruptions
Can inject large amounts of ash, dust, and sulfur dioxide aerosols into the stratosphere which impact global temperatures for a few years.
Milankovitch Cycles
Describe variations in Earth's orbit around the Sun and the tilt of its axis where orbital changes influence the amount of solar radiation reaching different parts of Earth at different times, impacting global temperatures over long timescales.
The Greenhouse Effect
A natural process that warms the Earth’s surface and acts like a giant blanket which traps some of the Sun's heat and preventing Earth from becoming a cold, desolate rock.
Human Activities that Influence The Greenhouse Effect
Burning Fossil Fuels, Deforestation, Industrial Processes, and Agricultural Practices
Consequences of the Enhanced Greenhouse Effect
Rising Global Temperatures, Increased Extreme Weather Events, Sea Level Rise, Ocean Acidification, and Disruptions to Ecosystems
Landscape
All the visible features of an area of countryside or land, often considered in terms of their aesthetic appeal.
Natural Landscapes
Primarily shaped by natural processes over long timescales.
Built Landscapes
Dominated by human-made features.
Uplands
Characterized by higher elevations, steeper slopes, and harsher weather conditions compared to lowlands.
Lowlands
Characterized by fertile soils, making them ideal for agriculture and supporting a higher population density.
Glaciated Landscapes
Recognizable by features like U-shaped valleys carved by glaciers, corries (circular hollows), and pyramidal peaks.
Weathering
The breakdown and alteration of rocks and minerals at the Earth's surface, preparing them for erosion.
Mechanical Weathering
Physical processes break down rocks into smaller fragments without altering their chemical composition.
Chemical Weathering
Chemical reactions transform rocks and minerals, changing their composition.
Biological Weathering
Plants, animals, and microorganisms contribute to rock breakdown.
Mass Movement
Downslope movement of rock, soil, and other debris under the influence of gravity.
Slides
Rapid movement of large masses of rock or debris down a slope.
Slumps
Downward and rotational movement of a block of rock or soil along a curved surface.
Earthflows
Slow, continuous movement of saturated soil down a slope.
Abrasion
Rocks and particles grind against each other, causing wear and tear.
Hydraulic Action
Moving water (waves, rivers) exerts force, breaking off rock fragments.
Attrition
Particles collide and break into smaller pieces as they are transported.
Solution
Water dissolves some minerals, carrying them away in solution.
Transport
The movement of eroded particles by wind, water, glaciers, or gravity.
Traction
Particles are dragged or rolled along the ground by wind or water.
Saltation
Particles bounce and skip along the surface, propelled by wind or water.
Suspension
Fine particles are carried within a fluid (air or water) for extended periods.
Deposition
The accumulation of transported sediment in new locations which occurs when the agent carrying the particles loses energy and can no longer transport them.
Sedimentary rocks
Layers of deposited sediments get compacted and cemented over time, forming sedimentary rocks like sandstone and shale.
Alluvial plains
Floodplains formed by the deposition of sediments by rivers.
Windblown deposits
It is when sand dunes are formed by the accumulation of wind-blown sand.
Glacial deposits
Till (unsorted glacial debris) and moraines (deposits left by glaciers) are formed by the deposition of material transported by glaciers.
The erosive power of waves depends on factors like wave height, wave frequency, and the type of rock the waves are hitting.
Erosion
The geological process in which earthen materials are worn away and transported by natural forces such as wind or water.
Headlands
Areas of high land that jut out into the sea.
Bays
Curved indentations in the coastline between headlands.
Differential Erosion
A geological process in which different rock layers or materials are eroded at varying rates due to differences in their resistance to weathering and erosion.
Caves
Waves constantly batter the coast, and over time, cracks and weaknesses in the rock are exploited.
Arches
As caves grow deeper, the roof thins and weakens. Eventually, the roof collapses, leaving behind a natural arch.
Stack
A tall, isolated pillar of rock standing offshore.
Beach
An accumulation of loose sediment (sand, pebbles, or cobbles) deposited by waves along the coast.
Spit
Are elongated narrow strips of land that project out from the coast at an angle.
Waterfall
Occurs where the river encounters a sudden drop in elevation, often due to differences in rock hardness.
Gorge
Typically deep and narrow, with exposed rock faces showcasing the power of erosion.
V-shaped Valleys
Deep, narrow valleys with steep sides that form in the upper course of a river.
Floodplain
A flat, low-lying area bordering the river channel.
Meander
As a river flows across a floodplain, it may develop bends or curves called meanders.