We recognise that climate change is going to be a big issue over the coming decades. We also recognise that there is a gap between peer reviewed publications, often difficult for non-specialists to understand and usually requiring payment or a university affiliation to read, and blogs, often frequented by “deniers” and “alarmists” whose enthusiasm in their cause is not matched by their understanding of the issues. This site is an honest, if as yet incomplete, attempt to bridge that gap.

We also believe that it is wrong for science to be politicised; not in the sense that it is used in political decision making, that is inevitable and to be welcomed, but in the sense that selected scientific findings are used to support or contradict a viewpoint using the rhetorical tactics of politicians.
Neither. We have not included or excluded data sets simply to maintain a balance. We have tried to find the best long-term data on issues of importance regardless of which “side” it seems to support. For example, we have re-analysed the radio-sonde data and shown there is a “hot spot” which is of a similar order of magnitude to that predicted by climate models and presented by the IPCC. On the other hand the 150-year record of hurricanes making landfall in the US shows there have been many variations but no significant trend over that period.

We also recognise that there are many unsolved problems whose solution could change the way we think. Examples of this are how the Milankovitch cycles affect the climate and the cause of cycles such as El Niño.
This was a two stage process. Firstly we decided which parameters to include. Some of these were obvious, such as temperature. Others were included as they are considered by many to be relevant even if their link to climate change is not proven, such as sunspots. Secondly we selected data bases which had a long duration and were from sources generally accepted as reliable. In most cases the preparation of the data sources we used has been described in peer-reviewed publications. Over time we will add further parameters and data sets.
A lot of the raw data available on the internet are held in files with different formats. Most of the data on our site have been converted from their original format to Comma Separated Value (CSV) files which can be imported to spread-sheet programs, such as Excel, and databases, such a Access or Filemaker.

Some data are recorded at irregular intervals. One example of this is ice core data. This makes it difficult to compare data of different types or from different ice cores. The method used on this site is to produce a continuous record at the regular time step interpolating between observed values. By choosing a fine time step little detail is lost from the original record but comparison becomes much easier.

For some variables, due to instrument malfunction or other reasons, data sequences are not continuous. When there are gaps in the data it is difficult to identify trends. In such cases, providing the gap is of limited duration and provided the infilling does not it itself lead to false conclusions, we have infilled missing data. Various methods have been used and these are explained fully where appropriate.

Some files give the year value as before present (BP) with positive values for the year number; this means that time runs from right-to left when plotted normally. Other files give the calendar year; this means that time runs from left-to-right. For consistency all files are re-ordered with negative year values for times before present. This means that time on the graphs presented here always goes from left-to-right.
The data were all downloaded from sites recognised for the quality of their data; in most cases described in peer-reviewed articles. All the files we processed are available for download free of charge. We give the sources and references to original data on this site which enable users to carry out their own quality checks. We are planning to add additional information on the validation checks we have carried out ourselves.
Supplementary information can accessed from the data downloads pages in each section.
Each package consists of graphs (as shown on the website) and the CSV files used to create the graphs. For each file, the contents description found on the downloads page includes the time-step, the duration and the number of variables used to construct each graph. The files for each item are downloadable in zip file format.
This type of file can be imported in spread sheets on Windows, Macintosh and UNIX.
Yes, but we reserve the right to accept or reject contributions. Please send us a message from the contact page and we will reply with an email address for you to send us attachments.