In a previous post I discussed the Old Weather project which is using volunteers to transcribe the hand-written weather data from Royal Navy ships logs in the World War 1 period. The good news is the first 243 ships have been completed (providing data scattered throughout the period 1914-1923), and some simple analysis shows whether this data can help reconstruct past Atlantic atmospheric variability. Continue reading Reconstructing Atlantic atmospheric variability
Category Archives: variability
Time of emergence of climate signals
The time at which the signal of climate change emerges from the ‘noise’ of natural climate variability (Time of Emergence, ToE) is a key variable for climate predictions and risk assessments. Continue reading Time of emergence of climate signals
Uncertainty in temperature variability
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
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
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
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?
Arctic predictability
After attending a recent workshop on Arctic predictability, I thought a brief discussion on sea-ice variability and potential predictability might be of interest. Continue reading Arctic predictability
Atlantic multi-decadal variability
Observations of Atlantic SSTs show significant multi-decadal variability since 1870 (see red line in figure 2 below), often termed the Atlantic Multi-Decadal Oscillation (AMO), though there is no clear evidence that it is really an ‘oscillation’. Continue reading Atlantic multi-decadal variability