Learn: Climate Change Fundamentals

Climatology

The scientific study of climate and weather conditions averaged over time.

Instrumental Period

Begins around 1860 with reliable temperature instrumentation and quasi-global data.

Mercury Thermometer

Invented by Daniel Fahrenheit in 1714.

Proxy Data

Indirect measures of past climate like tree rings, coral skeletons, and ice cores.

Tree Rings

Larger rings indicate warmer, wetter weather.

Ice Cores

Glacial ice cores provide climate data going back 700,000 years or more.

Greenhouse Effect

Greenhouse gases redirect heat rising from Earth's surface back down.

Milankovitch Cycles

Cycles affecting solar radiation: eccentricity, axial tilt, and axial precession.

Eccentricity Cycle

Earth's orbital shape varies on a roughly 100,000-year cycle.

Methane Heat Trapping

Methane traps heat 21 times more effectively than CO2.

IPCC Role

The Intergovernmental Panel on Climate Change reports every 5 years.

Sea-Level Rise Causes

Caused by thermal expansion and melting ice from land and glaciers.

Ocean Acidity Increase

Increased by 30%, decreasing ocean water pH by about 0.1.

Phenology

The study of seasonal behaviors within species' geographic ranges.

Second Biggest GHG Source in US

Home energy use, coming right after transportation.

Demography

The statistical study of human populations and their characteristics and growth consequences.

Thomas Malthus

Wrote 1798 essays predicting food production could not support exponential population growth.

Neolithic Era Population

About 10,000 years ago, global population was 2 to 3 million people.

Global Population 1804

The year human population first reached 1 billion.

Great Famine of 1315-1317

Historical catastrophe that killed 10 to 25% of Europe's population.

Black Death

Plague between 1347 and 1352 that killed one-third of Europe's population.

Rapa Nui (Easter Island)

Society that degraded once-fertile land, leading to drastic population reductions.

Chaco Canyon Anasazi

Society forced to abandon the area due to a 50-year drought in the 12th century.

Greenland Viking Colonies

Perished or abandoned areas after the Little Ice Age following 400 years of livestock grazing.

William Vogt

Author of 1948 book Road to Survival predicting 75% of humans would be wiped out at 3 billion.

Paul Ehrlich

Author of the 1968 book The Population Bomb predicting population collapse.

Crude Birth Rate

The total number of births per thousand people per year.

Crude Death Rate

The total number of deaths per thousand people per year.

Rate of Natural Increase (RNI)

Calculated as (Births - Deaths) / population, ignoring immigration and emigration.

Total Fertility Rate (TFR)

The average number of children born to a woman over her reproductive life.

Replacement Fertility

A TFR of 2.1 where the population does not grow or decline.

Factors Influencing Birth Rates

Includes education, wealth, child labor value, cost of children, marriage age, and urbanization.

Factors Influencing Death Rates

Includes nutrition, sanitation, healthcare, and conflict.

Land Required Per Person

Today requires 0.2 hectares per person, with projections to drop to 0.1 hectare.

Carrying Capacity

The maximum number of individuals of a species that a habitat can sustainably support.

US Consumption Impact

If all 7 billion people consumed like the average US citizen, it would take over four Earths.

Contraception and Fertility

Safe contraception technologies have greatly reduced the probability of pregnancy and fertility rates.

China's One-Child Policy

Enforced in 1980 to limit rapid population growth, reducing TFR to 1.6 by 2000.

Iran's Population Policy

Late 1980s free clinics distributed free contraception, reducing TFR from 7 to 2.1 in 10 years.

Singapore's Population Incentives

Offered online matchmaking services and cash bonuses due to a low TFR of 1.14.

Eugenics and Forced Sterilization

Unethical historical policies implemented in the US and Nazi Germany to eliminate undesirable traits.

Brazilian Soap Operas

Studied by Eliana La Ferrara for encouraging birth control use and reducing fertility rates.

Demographic Transition Model

Shift from high birth and death rates to low birth and death rates as human development index increases.

Mortality Transition

Phase of demographic transition where access to food, water, and medical care lowers death rates.

Fertility Transition

Phase where population growth slows because birthrates decrease due to societal changes.

Demographic Window

A time when working-age population dominates and dependents under 15 or over 64 are low.

Stability Transition

Final period of demographic transition where low death rates match low birth rates for zero growth.

Youth Bulge

An explosion of young people caused by a prolonged period of low mortality and high fertility.

Population Pyramids

Histograms displaying age structure and sex ratios of a population.

Population Momentum

Phenomenon where population continues to grow for a generation even after TFR drops to 2.1.

Human Development Index (HDI)

A composite statistic measuring health, education, and economics of a population.

Urbanization and TFR

Urbanization tends to decrease TFR, with global urban TFR averaging 2.2 compared to 3.0 in rural areas.

Education of Women and TFR

Educated women marry later and have lower fertility rates, heavily impacting population growth.

Cairo Consensus

1994 international agreement holding that development goals require balancing rights and opportunities of both genders.

Literate Life Expectancy (LLE)

The average number of years in a person's life with the ability to read and write.

GDP and Consumption Correlation

Economic improvement raises living standards, increasing consumption even as population stabilizes.

Richest Billion Consumption

Consumes more than 32 times the average of the other 6 billion people on Earth.

I = PAT Equation

Environmental impact (I) equals Population (P) times Affluence (A) times Technology (T).

Daniel Fahrenheit

Invented the mercury thermometer in 1714, enabling standard temperature records.

Central England Temperature Data

Historical temperature series beginning monthly in 1659 and daily in 1722.

Weather Satellites

Satellites like TIROS-1 and the GOES series that have provided high-level data since the 1970s.

Surface Air Temperatures (SAT)

Temperatures recorded by numerous terrestrial weather stations.

Marine Air Temperatures (MAT)

Temperatures recorded across the oceans, which cover 71% of Earth's surface.

Argo Program

International program using floating probes that drift for 4 to 5 years and report via satellite.

Global Drifter Array

Oceanic program recording sea surface temperature, atmospheric pressure, wind, and salinity.

Geothermal Gradients

Measuring bores deep into Earth's crust to reconstruct historical surface temperatures.

Isotopic Analysis of Ice Cores

Using stable isotopes of oxygen (16O, 17O, 18O) in ice cores to estimate past temperatures.

Cretaceous Period Climate

Fossil evidence indicates that polar regions were forested during this period.

Snowball Earth

Period 700 million years ago when glacial sediments near the equator suggest complete ice cover.

Albedo

The reflectivity of light-colored surfaces on Earth that impact solar radiation absorption.

Plate Tectonics and Climate

Drifting continents alter solar radiation access and ocean current heat distribution.

Milankovitch Cycles - Axial Tilt

Changes in Earth's axial obliquity on a 41,000-year cycle affecting seasonal extremity.

Milankovitch Cycles - Axial Precession

Changes in the direction of Earth's rotational axis, similar to a spinning top.

Krakatoa Eruption

1883 volcanic eruption that decreased average Northern Hemisphere summer temperatures by 0.73° F.

Atmospheric Lifetime of CO2

Natural atmospheric life of carbon dioxide ranges from 50 to 200 years.

Methane Emission Sources

Released from coal mines, natural gas leaks, rice farming, livestock production, and landfills.

Nitrous Oxides (N2O)

Greenhouse gases increased by 20% since preindustrial times, trapping heat 310 times more effectively than CO2.

Halocarbons

Synthetic chemicals used in aerosols and refrigerants that act as powerful greenhouse gases.

Phenology and Climate Change

Global warming alters the seasonal timing of biological activities and species behaviors.

Positive vs Negative Feedback Loops

Positive feedback enhances the original change, while negative feedback counters it.