To be forward thinking it’s important for Oxford City Council to think about future changes. This includes changes to the climate.

The UK Climate Impacts Programme (UKCIP) supply climate projections based on work by the Met Office Hadley Centre. See findings for Oxford below.

Key Findings for Oxford (2030s)

• Average air temperature = 1.0 - 2.6 degrees C increase “likely”
• The ‘central estimate’ for the warmest day of summer = 2 degrees C increase
• The ‘central estimate’ for winter precipitation (rain, sleet and snow) = 8.6% increase
• The ‘central estimate’ for summer precipitation = 9.4% decrease

Summary Climate Projections for Oxford in the 2030s (medium global emissions scenario)

Air temperature	Average annual air temperature is likely to be 1.0-2.6oC higher. The average for the summer months is likely to be higher (0.8-2.9oC).
Hottest day temperature	The central estimate for the change in temperature for the warmest day of summer is a 2oC increase
Coldest day temperature	Autumn days shows the highest likely rise in temperature on the coldest day. The central estimate for autumn’s coldest day is a 1.8oC rise.
Hottest night temperature	The warmest autumn nights are likely to increase between 0 and 3.3oC. The central estimate for the warmest winter warm nights is a 1oC rise.
Coldest night temperature	The temperature of the coldest winter night is likely to increase by between 0.4oC and 4oC.
Precipitation	The central estimate for winter rainfall is an increase of 8.6%. In winter the likely range between -2.1% and 21.7%. The central estimate for the summer month is a decrease of 9.4%.
Wettest Day	The central estimate for precipitation on the wettest day of winter is a 8.5% increase.
Relative humidity	Relative humidity in summer is likely to decrease 2-10%.
Cloud cover	The central estimate for mean cloud cover is an increase of 0.7% in winter and a decrease of 3.2% in spring. Summer cloud cover is estimated to be likely increase by 0.6-0.7%.
Wind	Currently there are no projections for wind

How were these climate projections made?

Climate is a 30 year average of weather conditions such as temperature and rainfall. Climate scientists at the Met Office Hadley Centre used hundreds of  different model runs to plot how the climate might behave over the next 20-80 years. These model runs all came up with slightly different results of how climate might change within realistic ranges.  After also adding in work from other centres, the Met Office brought all these results together to create a ‘probability curve’ of likely projections for the UK, split up in to grid squares of 25km2 (25 by 25 km squares). Changes are relative to the climate period 1961-1990.

What are the key findings based on?

The key findings and information below is from the projections for Oxford’s main grid square for the medium global emissions scenario for the 2030s (2020-2049). See more information about emissions scenarios on the UK Climate Projections website.

What is the ‘central estimate’?

The ‘central estimate’ means the middle point on the probability curve. This is not necessarily ‘most likely’  and usually does not occur at the peak of the graph but means that, based on the projections, conditions are as likely to be above it as below it, see image below.

What does ‘likely’ mean here?

These sort of projections cannot tell us what is ‘most likely’. Instead the projections can tell us that average air temperatures are ‘likely’ to be between 1 and 2.6 degrees higher in the 2030s. By ‘likely’ we mean that only 10% of the models showed changes either less than 1 degree C or over 2.6 degrees C, see chart below.