Climate questions: Where can I find reliable information about climate science?

There is a lot of information on climate change science available in the media and on the internet – but how can you ensure what you are reading is independent and not influenced by personal, social or political agendas? Science relies on the continued questioning and challenging of ideas. The peer-review process provides a mechanism to quality control scientific discourse and therefore peer reviewed papers provide a reliable and quality assured source of information on climate change science.

Climate questions: Has global warming stopped?

All measurements of the climate system indicate the long term warming trend is continuing. It is inappropriate to use short term data sets to determine long term trends.

Climate variability within a changing climate

The physical evidence shows that the climate has warmed over the last century. Analysis and physical
interpretation of climate data reveals an underlying or background global warming of around 0.74°C since
the start of the 20th century.

Climate questions: Can the warming of the 20th century be explained by natural processes?

It is often claimed that the observed warming of the climate system results from natural climate processes rather than being human-induced. However, there are no known natural factors that can explain the observed warming. The Intergovernmental Panel on Climate Change finds it is very likely that most of the observed global warming since the mid 20th century is due to anthropogenic increases in greenhouse gases.

If scientists are unable to forecast next week's weather accurately, how can they predict the climate in the next 50 to 100 years?

Weather is highly variable, making it difficult to predict over the short term whereas climate is defined as the average weather over the long term. Scientists can project future climate because the underlying processes are well understood.

Climate questions: How reliable are climate models?

The ability of climate models to project future climate is often questioned. There will always be a range of uncertainty in climate projections. Climate models, which are based on the laws of physics and thoroughly tested, provide credible quantitative estimates of future climate change.

Climate questions: Is there an inconsistency between observed and modelled patterns of warming in the lower atmosphere?

It is commonly claimed that a predicted fingerprint of climate change – a warming (or hot spot) in the lower troposphere – is missing from the measurements. Recent reanalysis of the data has established that observations are not inconsistent with the modelled patterns of warming for the troposphere. Thus there is no ‘missing’ hot spot.

Climate questions: Understanding current climate change in a palaeoclimatic context

The Earth’s climate has varied naturally over hundreds of millions of years – why should we believe humans are causing current changes? Understanding past changes between glacial and interglacial periods helps us to understand how unusual the current warming is. For example, the linear warming trend over the past 50 years of 0.13 °C per decade is much more rapid than the rate of warming between ice ages and warm interglacial periods of around 0.01 °C per decade.

Climate questions: Have methane levels stabilised?

Following almost a decade with little change in global atmospheric methane, new measurements show renewed atmospheric growth starting in 2007, continuing through 2008 and starting to wane in 2009. This renewed growth has lead to concerns by some science commentators that large quantities of methane are becoming destabilised as the planet and the oceans heat up.