Weather: space & time differences

Prof. Grant Bigg, Head, Department of Geography, University of Sheffield

The Climate System

The Climate System

(Naturally varying)

The Climate System

(directly anthropogenically varying)

Differences (or variability) over different timescales

• Millennial

• Centennial

• Decadal

• Interannual

• Seasonal

• Daily

• Hourly

Millennial cycling

Centennial change

Fig. 6.10 IPCC (2007)

Decadal change

Global surface air temperature(IPCC Fig. 3.6)

Interannual change

Central England Temperature

(from www.metoffice.gov.uk/hadobs)

oC

Seasonal change

Central England Temperature 2009-2011

(from www.metoffice.gov.uk/hadobs)

oC

Daily change

Central England Temperature 2012

(from www.metoffice.gov.uk/hadobs)

Hourly change

Google Earth.lnk

Let’s look at Google Earth’s weather overlays for hourly variation

Then go to spatial scales

• Stop slide show

• Go to Google Earth (pre-set to Weather & Terrain only)

• Expand weather layer

• Comment on cloud patterns observed over eastern Atlantic

• Click cloud animation in Temporary Places

• Turn off weather layer

• Drag play pointer slowly along describing time evolution and introducing spatial scales

• Go to yesterday evening and zoom to UK or some other region where overnight variation

• Point to reduced scale and zoom in to area

• Move through sequence commenting on what it reveals about space and time scales

• Go over UK if not there

• Turn on weather layer

• Draw attention to weather data and temperature

• Zoom in to bring more stations

• Click on station – note features (and that probably from analysis, not real data)

• Click on hourly and details to give hour by hour step

• Note forecast only, from US Weather Channel

• Remove and note spatial limitations of this detailed data to major towns

• Now switch to radar data and move to clear rainfall zone

• Note 3 hour 30 minute delay between radar and cloud (radar ahead) – hence mismatch in patterns

• Activate radar animation

• Follow through, discussing spatial and temporal scales

Sources of data or ideas

• Royal Meteorological Society MetLink site (www.metlink.org)

• Meteorological Office Weather Observations Website (wow.metoffice.gov.uk/home)

Suggestions For Weather Space- Time Differences Questions That Can Be Explored With Student Observations

• Variation over time at home (hourly, daily or longer)

• Variation over school catchment at same time (synoptic view)

• For those with solar panels – how does power generation relate to cloudiness?

Any Questions?