The cost of one barrel (159 litres) of crude oil in US dollars. This dashboard uses Brent Crude from 1987 onwards and WTI (West Texas Intermediate) before 1987 as a proxy. Both are international benchmark prices used to value global oil trade.

The most widely used global oil price benchmark, sourced from the North Sea. Used to price approximately 2/3 of the world oil supply. Preferred in this dataset from 1987 when EIA records begin. Slightly higher than WTI due to transportation cost differences.

The main US oil price benchmark, extracted in Texas and Oklahoma. Used in this dashboard as a proxy for global oil prices before 1987 when Brent data is unavailable. WTI and Brent track closely but can diverge during supply disruptions.

Mb/d = Million barrels per day. kbd = Thousand barrels per day. These measure how much oil a country or the world actually uses (burns) each day. Consumption includes transport, industry, heating, and electricity generation. Global consumption grew from ~31 Mb/d in 1965 to ~101 Mb/d in 2024.

How many thousand barrels of crude oil a country extracts from the ground per day. Production differs from consumption — a country can produce much more than it uses (e.g. Saudi Arabia) or use more than it produces (e.g. USA historically). Wars often disrupt production in the conflict country.

The percentage change in average oil price during a war compared to the average price in the 3 years before the war. Formula: ((During avg - Before avg) / Before avg) x 100. A positive value means oil got more expensive during the war. The Iran-Iraq War caused the biggest spike at +57.7%.

EJ = Exajoule. One exajoule = 10^18 joules. This measures total energy consumed from all sources (oil, coal, gas, nuclear, renewables) before conversion losses. It is a broader measure than oil consumption alone and helps understand the full energy footprint of a country or the world.

Gt = Gigatonne = 1 billion metric tonnes. This is the standard unit for measuring global greenhouse gas emissions. In 1960, global CO2 was 9.4 Gt. By 2024 it reached 38.6 Gt — a 311% increase. Most CO2 comes from burning fossil fuels (oil, coal, gas) and deforestation.

Mt = Megatonne = 1 million metric tonnes. Used for smaller country-level measurements. 1,000 Mt = 1 Gt. Country emissions are typically expressed in Mt while global totals use Gt. For example, Kuwait emits ~0.033 Gt (33 Mt) per year under normal conditions.

CO2 emissions broken down by the fuel that produced them. Oil CO2 comes from burning petrol, diesel, jet fuel and heating oil. Coal CO2 comes from power plants and industry. Gas CO2 comes from natural gas burning. Coal produces the most CO2 per unit of energy, which is why it dominates the stacked chart despite oil wars.

Total CO2 emissions divided by the country or world population, expressed in tonnes per person per year. This removes the population size effect and shows the emissions intensity of each person's lifestyle. The global average peaked around 4.7 tonnes per person in 2012 and has stayed roughly flat since.

The year-on-year percentage change in global CO2 emissions. Positive = CO2 went up vs the prior year. Negative = CO2 went down (rare — happened in 1980, 1992, 2009, 2020 recession/COVID). Wars sometimes cause a temporary dip in the war country but rarely reduce global CO2 growth because other countries fill the supply gap.

In this study, a Tier-1 war is defined as a major armed conflict (more than 1,000 battle deaths per year by UCDP definition) fought in or between countries that are significant oil producers or that sit on critical oil supply routes. All 6 wars analyzed qualify: Arab-Israeli, Iran-Iraq, Chad-Libya, Gulf War, Iraq War, and Russia-Ukraine.

Each war is analyzed across 3 phases within a study window. Before = the 3 years preceding the conflict start. During = the active conflict years. After = the 3 years following the conflict end. Averages for oil price, CO2 and consumption are calculated separately for each phase to measure the war's impact.

A country's annual defence budget expressed as a percentage of its Gross Domestic Product (GDP). Wars typically cause a sharp spike in this metric as governments increase defence budgets. The global average was around 3-4% during the Cold War and has fallen to around 2% in recent decades. Data from SIPRI covers 193 countries from 1949.

The UCDP (Uppsala Conflict Data Program) classifies conflicts by intensity. Level 2 = war, defined as more than 1,000 battle-related deaths in a calendar year. Level 1 = minor conflict (25-999 deaths). This study uses only Level 2 conflicts to ensure only major wars with real oil market impact are included.

A statistical measure of the linear relationship between two variables, ranging from -1 to +1. r = +1 means perfect positive relationship (both rise together). r = -1 means perfect negative relationship (one rises as the other falls). r = 0 means no relationship. In this study: oil consumption vs CO2 = r=0.983 (near-perfect), oil price vs CO2 = r=0.856 (strong), military spend vs oil price = r=-0.74 (moderate negative).

A technique that sets all variables to 100 at the base year (1960) so they can be compared on the same chart regardless of their original units. A value of 400% means the variable is 4x its 1960 level. This removes the unit problem (you cannot plot $/barrel and Gt on the same scale) and shows relative growth rates instead.

A chart with two different Y-axes — one on the left and one on the right — allowing two variables with different units to be plotted together. In the Strategic Timeline, the left axis shows oil price in $/barrel and the right axis shows CO2 in Gt. This reveals whether they move together over time without needing to normalise the data.

The primary analytical framework used in the War Scenarios section. For each conflict, the average value of oil price, CO2 and oil consumption is calculated separately for the before, during and after phases. Comparing these three bars shows whether the war caused a significant change in each variable and whether the effect was temporary or permanent.

The Uppsala Conflict Data Program, maintained by Uppsala University (Sweden) and the Peace Research Institute Oslo (Norway). Considered the gold standard for conflict data. Records all armed conflicts globally from 1946 to present with conflict type, location, parties, intensity level and battle deaths. Used to identify and verify all 6 wars in this study.

The Stockholm International Peace Research Institute tracks military spending for 193 countries from 1949. Data is expressed as % of GDP, per capita and in constant USD. Considered the most comprehensive and reliable source for defence expenditure data globally. Updated annually.

A comprehensive CO2 and greenhouse gas emissions dataset maintained by Our World in Data, built on data from the Global Carbon Project, BP Statistical Review and IEA. Covers 254 countries and territories from 1750 to 2024 with over 50,000 rows. Includes CO2 by source (oil, coal, gas), per capita, per GDP and cumulative totals.

Formerly the BP Statistical Review of World Energy (published annually since 1952). One of the most authoritative sources of global energy data. Covers oil, gas, coal, nuclear and renewables production and consumption for 141 countries from 1965. Used in this study for oil production and consumption data (oilprod_kbd, oilcons_kbd).

The Federal Reserve Bank of St. Louis maintains one of the world largest economic databases. The WTI oil price series (WTISPLC) used in this study goes back to 1946 with monthly observations, providing the longest available oil price history. Data is freely available and updated in real time.

The statistical agency of the US Department of Energy. Provides comprehensive energy data including the Europe Brent Spot Price FOB series used as the primary oil price source from 1987 onwards in this study. FOB (Free On Board) means the price at the point of loading, excluding shipping costs.