400 ppm exceeded at Mauna Loa

The Manua Loa weather station. Photo: flickr.com Flatbush Gardener cc by-nc-nd

The symbolic level of 400 ppm of carbon dioxide in the atmosphere has been exceeded at Mauna Loa in Hawaii for the first time since records began in 1958. It is the oldest of all the atmospheric measurement stations in the network of stations that the Global Atmosphere Watch coordinates. It was on 9 May this year that a reading of 400.3 ppm was recorded as the daily average. Levels exceeding 400 ppm have previously been recorded at several more northerly stations. The first was Barrow in Alaska, where the threshold was exceeded back in April 2012. The plus 400 ppm reading at Mauna Loa has since been followed by stations at locations closer to the equator, including the Canary Islands.

The highest concentrations of carbon dioxide over the year generally occur during the northern atmospheric spring, just before large amounts of carbon dioxide are absorbed by growing vegetation.

The global annual average concentration in 2011 was 390.9 ppm, that is 40 per cent higher than pre-industrial levels. With the current rate of increase it is estimated that the global annual average concentration will exceed 400 ppm by 2015 or 2016.

Carbon dioxide is responsible for 85 per cent of the increase in radiative forcing – the warming effect on our climate - over the past decade. Between 1990 and 2011 there was a 30 per cent increase in radiative forcing because of greenhouse gases.

United Nations Environment Programme, Press release, 14 May 2013
The Mauna Loa record, systematically zooming in to the finer more recent data

In this issue

Warming can be limited to 1.5°C

There are reduction pathways that would make a global target of below 1.5°C possible, but they require negative CO₂ emissions in the second half of this century.

Editorial: Last warnings?

For the last 25 years environmental organisations around the world have been trying to warn the world about the threat of climate change and demand urgent and steep reductions in greenhouse gases.

Shale gas has lost its lustre

The “Golden Age” of shale gas, heralded by the International Energy Agency (IEA) a year ago, may not arrive after all, at least not in Europe. The promises of plenty, soon and cheap are not materialising.

EU energy tax reform stalled

Poland and Romania block even small steps toward technology-neutral fuel taxes in the EU.

Need for stronger EU action on air pollution

World Health Organization calls for tightening of Eurpean Union air quality standards.

Sea levels might rise 2 metres for each degree of warming

Prehistoric data has been used to simulate possible sea levels over the next two millenia.

Agreement on equity issues essential

The equity knot remains to be cut before we can see a new global climate agreement. Climate Action Network (CAN) has just launched a proposal.

Shipping air pollution costs €60 billion per year

Total health-related costs in Europe caused by air pollutant emissions from international shipping are expected to increase from €58 billion to €64 billion between 2000 and 2020.

Ship emissions down in the Baltic and North Sea

Switching to low-sulphur marine gas oil and lowering cruising speeds can reduce shipping emissions of air pollutants and greenhouse gases.

Air pollution causes 210,000 deaths each year

Road transportation and power plants are the leading causes of air-pollution-related deaths in the US, contributing to 53,000 and 52,000 early deaths respectively each year.

Fewer congestion charge exemptions

From 1 July, new cars in London will no longer be able to be registered for the Greener Vehicle Discount which gave cars with emissions under 100 grams of CO₂ per kilometre ..

Germany blocks CO2 deal for cars

The agreed CO₂ rules for cars are threatened by demands from Germany to re-open the negotiations.

High potential to further cut pollution from power plants

Emissions of the main air pollutants – sulphur dioxide, nitrogen oxides and dust – could be significantly further reduced if the emission levels associated with the best available techniques were to be achieved.

New tool raises awareness of air pollution impact

Clean Air in London has launched a new app that warns people about the dangers of air pollution and gives advice about how they can protect themselves.

7th Environment Action Programme agreed

In late June, representatives from the outgoing Irish presidency and the European Parliament agreed the final text of the EU’s seventh environment action programme (7EAP) for the period to 2020.

Coal power must be replaced with green energy

An additional 32,000 life years would be lost every year if the coal-fired power plants currently under construction or being planned in the EU go into operation.

More food, less climate change

Improved meat production in Latin America and higher crop yields in Africa are key measures to reduce greenhouse gas emissions from land-use change, while improving food security.

New CAP deal: “little more than greenwash”

The new Common Agricultural Policy (CAP) for the period 2014–2020 was sold as a green reform, when the Commission launched its proposal a bit more than a year ago. For the first time, direct payments, the EU budget’s biggest single expenditure, would require ..