It is well known that there is considerable uncertainty in the projected response of climate models to increases in radiative forcing. However, there is also considerable uncertainty in the model simulated internal variability. Continue reading Uncertainty in temperature variability
Climate uncertainty: moving from 'what' to 'when'
Update (23/10/11): The full article has now been published in Nature Climate Change
Climate projections (such as from the IPCC) usually consider the question of “what will happen to our future climate”. But, this question may be more informative if it is changed to “when will it happen”? Continue reading Climate uncertainty: moving from 'what' to 'when'
Uncertainty in uncertainty
There has been much discussion recently on whether GCMs participating in intercomparisons, such as CMIP3 and CMIP5, are ‘independent’. But if they are not, how does this make a difference to the uncertainty in our projections for future climate? Continue reading Uncertainty in uncertainty
Trends in Central England Temperature
Previous posts have discussed climate variability in general, and modelled decadal trends in temperature specifically. However, I should have considered decadal trends in observations as well, especially as there is a long temperature record available for the UK. Continue reading Trends in Central England Temperature
Visualising climate with 2d colour bars
A recent paper by Teuling et al. suggested the use of 2d colour bars for visualising climate fields. I thought I would give this a try – and Ryan Teuling was kind enough to provide the code to construct the colour bars. Continue reading Visualising climate with 2d colour bars
Learning about past climate from ships logs
Understanding the climate of the past is extremely valuable to help put modern weather observations into a long-term context. Although we have considerable records of past weather, especially over land, more data is always welcome. Given the British obsession with the weather it is perhaps of no surprise that more data is available, it is just buried in hand-written logbooks. Transcribing this data is normally a time-consuming and expensive task…. Continue reading Learning about past climate from ships logs
When to use uncertain climate forecasts
Climate models produce projections of changes in climate from the present day, but these projections have a range, or spread. A simple measure of the confidence in a forecast would be the signal-to-noise ratio, r, of the size of the projected change to the spread around that change. An important question is ‘when does the spread in the forecasts become so large that the forecast should not be used’? Continue reading When to use uncertain climate forecasts
What is a year?
A rather surprising question perhaps, but the answer is, ‘it depends’. There is no climatic reason to define a year from January to December, but that is what is generally done. But, is this the best definition? Continue reading What is a year?