Grams of CO2 produced for every passenger per kilometre travelled.
Air (domestic) – 316
Air (short haul) – 260
Air (long haul) – 210
Car (1 passenger) – 200
Car (1.56 passengers) – 128
Motor Bike
Cycle
Bus – 70
Coach – 25
Sea Ferry – 45
Train – 22
Taxis – 600 (1 passenger)
Reference 1: http://www.defra.gov.uk/sustainable/government/
“Green guide for buyers – Climate change (action sheet)”
Whats our goal?
- To reduce emissions of greenhouse gases covered by the Kyoto Protocol. Following the Kyoto Protocol, the UK has a legally binding target to reduce emissions of greenhouse gases to 12.5% below 1990 levels over the period 2008 -2012. 1
- To meet the Government’s domestic goal of a 20% cut in CO2 emissions below 1990 levels by 2010.
Did you know?
- Carbon dioxide is the most important greenhouse gas, and accounts for about 80% of all greenhouse gas emissions.
- The equivalent of 10 tonnes of carbon dioxide are generated from:
- Powering 86 PCs for a year or using 23,000 kWh of electricity.
- Running an average petrol car for 30,000 miles or 48,000 km.
- Flying 14 international long haul trips or 110 short haul trips.
- Travelling 165,000 km on a train.
- Running an articulated lorry over 5,000 miles or over 9,000 km.
- Refrigeration leakage over 2 years from an air conditioning plant in a medium sized office block.
- Emitting half a tonne of methane from a landfill site or from wastewater.
- World temperatures this century could rise by between 1.4 and 5.8 ° C resulting in less rain, spreading deserts, risks to food supplies, more storms and floods and an increase in infectious diseases like malaria and dengue fever 2.
- Projections show that emissions of HFCs will rise from 2.5 MtC (million tonnes of carbon) in 2000 to 3 MtC in 2020.
- Without action to reduce emissions of greenhouse gases, the number of people flooded annually by the 2080s is likely to increase seven-fold . About 13 million are currently affected each year.
- A report for the UN Environmental Programme published in February 2001 estimates that the effects of global warming could annually cost the world £200 billion by 2050.
The above figures give:
Electricity – 435 gm CO2 per kWh or 121 gm CO2 per megajoule
Car journey – 208 gm per vehicle kilometer
Train journey – 61 gm CO2 per passenger kilometer
Articulated lorry – 1,111 gm CO2 per passenger kilometer
Air Travel
For each short haul flight above 91 kgs of CO2 are produced
For each long haul flight 714 kgs are produced.
The figures on this site are much larger because flights are return flights and they include a radiative forcing index of 2 (The current IPCC figure is 2.7).
Assuming this is the case, the short haul filghts above are 699 kms (London to Hamburg one way). The long haul flights are 6803 kms (London to Nairobi one way).
Methane
Equating half a tonne of methane to 10 tonnes of CO2 assumes methane has a global warming potential(GWP) 20 times as powerful as Carbon Dioxide.
Methane actually has a much greater GWP.
It does, however, decay in the atmosphere so that little is left after 100 years. 23 is GWP of methane over 100 years. Over 20 years the GWP is 62 (http://en.wikipedia.org/wiki/Global_warming_potential)
If the next 20 years is considered crucial for climate change, methane should have a higher GWP than 20.
Any extra warming now causes positive feedbacks such as increasing the melting of the arctic ice-cap. This means emissions now are worse than the same emmissions in the future.