Transcript Document

Freak weather, or not?
I can’t believe this
I don’t know, I can
freak weather! We’ve
remember having lots
had so much snow,
of snow in the sixties,
and spring is really
and didn’t the River
late this year…
Thames once freeze
over?
Freak weather, or not?
Mind
the summers
… butyou,
I remember
the
seem
hotter,
and we’re
summer
of 1976
and
always
having
hosepipe
that was
a real
scorcher!
bans
and drought
I remember
queuing at
warnings…
the standpipe for
water…
Freak weather, or not?
• Many people believe that our climate is
changing and that it is due to global warming.
• There are three separate questions:
– Is the climate changing?
– If so, is it due to ‘global warming’?
– …and if it is, what’s causing the ‘global
warming’?
• We’re going to explore the first of these
questions.
Freak weather, or not?
Is the climate in Britain changing?
• What data would you need to have to be able to
give an informed response?
• How much of a change would there need to be
to convince you that there has or has not been a
change in the weather in recent years?
Freak weather, or not?
The following maps from the Met Office show the
average annual temperature for:
• 1961 to 1990
• 1971 to 2000
• 1981 to 2010
What can you tell from these maps?
Freak weather, or not?
What can you tell from these maps?
What can’t you tell?
• Some people think that summers are getting
hotter and winters are getting colder, others that
both summers and winters are getting warmer –
can you determine this from these maps?
Why do the Met Office show the average
temperature for 30 years rather than year by year?
Freak weather, or not?
Mean annual maximum temperature since 1900
15
Temperature
14.5
14
13.5
13
12.5
12
11.5
1900
1905
1910
1915
1920
1925
1930
1935
1940
1945
1950
1955
1960
1965
1970
1975
1980
1985
1990
1995
2000
2005
2010
11
Year
Is it getting warmer?
Freak weather, or not?
Choose one of these questions to work on:
• Are summers getting warmer?
• Are winters getting warmer or colder?
• Does it rain more or less than it used to?
• Is the weather in Southern England changing
more quickly than the weather in Northern
England?
…or pose your own question.
Freak weather, or not?
Exploring the question
• Decide what data you need and how you will
process and represent it.
• Think about what statistical methods or
representations are most appropriate.
Teacher notes: Freak Weather, or Not?
In this activity students consider common claims made in real life and use data to determine the truth
behind the claim. The emphasis is on using appropriate calculations and representations rather than
using every technique they know!
Since this is genuine real data, there are some avenues of exploration which will lead to a conclusion
that there is a trend and others that are less fruitful in this respect.
Content covered can be tailored to the class and can include producing and interpreting:
•
Averages
•
Range
•
Bar charts
•
Line graphs
•
Box plots
•
Moving averages and trend lines (Extension)
Teacher notes: Freak Weather, or Not?
Slide 5: Discussions in pairs or threes.
Certain points are helpful to pick up on, or pose as questions if they don’t arise from student
discussions.
What data do you need?
•
What variables would you look at? (temperature, rainfall/precipitation, humidity)
•
More precisely… Would you need annual temperature? Might you look at maximums and/or
minimums? Would you choose a certain month? Should you look at the whole of the UK or
choose certain areas?
How much of a difference is a ‘real’ difference?
•
This is a question with no ‘right’ answer, at this level, but just to convey a sense of a couple of
degrees warmer one year compared to the previous year is not as persuasive as a degree warmer
for a prolonged period.
.
Teacher notes: Freak Weather, or Not?
Slides 6 to 10: Met Office maps
These slides show the annual temperature for the UK for 30 year periods.
•
Because it’s the annual temperature, we have no idea whether it is:
– A small increase in temperature every month
– Winters the same but summers quite a bit warmer
– Winters are colder but summers are much hotter
Why look at blocks of 30 years?
•
Using a ‘time series’ approach is less affected by the variation in individual years
•
It is easier to spot emerging trends
•
It is more persuasive than looking at individual year variation
Understanding this will be helpful for students when they explore the data.
Slide 11
Small group discussion.
Question: How might we represent the data differently to gain a clearer insight?
•
Look at averages for decades instead of each year
•
Compare summer temperatures and compare winter temperatures
•
Compare box plots for each decade
•
Consider moving averages and trend lines (extension work)
Teacher notes: Freak Weather, or Not?
Slides 12 and 13: working on a question
•
You might ask different groups to work on different questions to build a bigger general picture
about climate change.
•
The emphasis is on using appropriate statistical techniques, relevant to the question they are
exploring – regardless of whether they use pencil and paper or ICT to construct or calculate.
•
The data for the questions can be explored using data from the accompanying Excel file.
•
Using ICT does allow a more thorough exploration of the data in a timely manner.
•
If students don’t have access to ICT facilities, then it is helpful to select and print a reduced range
of data for students to use.
•
If students pose their own questions, more data are available on the Met office website (links on
last slide)
•
A sheet for planning and summarising is attached.
•
A sample selection of summary data and charts is also attached for Teacher reference.
Teacher notes: Freak Weather, or Not?
Acknowledgements and links:
Met office maps: http://www.metoffice.gov.uk/climate/uk/averages/ukmapavge.html
Frozen Thames 1963 photo: http://www.thamesweb.co.uk/windsor/windsorhistory/freeze63.html
Women at standpipe 1976 photo: http://news.bbc.co.uk/1/hi/magazine/6729465.stm
Parker, D.E., T.P. Legg, and C.K. Folland. 1992. A new daily Central England Temperature Series,
1772-1991. Int. J. Clim., Vol 12, pp 317-342
http://www.metoffice.gov.uk/hadobs/hadcet/data/download.html
Alexander, L.V. and Jones, P.D. (2001) Updated precipitation series for the U.K. and discussion of
recent extremes, Atmospheric Science Letters doi:10.1006/asle.2001.0025.
http://www.metoffice.gov.uk/hadobs/hadukp/data/download.html