7. Oct 2010 – March 2012 Rainfall
% of 1971-2000 average
2 dry winters
Extreme weather
From drought...
8. Summer 2012 Rainfall
% of 1971-2000 average
Extreme weather
...to flood
Wettest June on
record
(180% of average)
3rd wettest summer on
record for Wales
(240% of average)
9. Important processes
• North Atlantic weather – North Atlantic Oscillation/ jet stream
• Tropical Pacific weather – El Nino
• Arctic Sea ice retreat
12. Little risk:
Action unlikely to be
required
Possible risk:
Action where assets
already close to design
limits
Some understanding:
More work to quantify
risks
Probable risk:
Action likely to be
required for most assets
Coastal
infrastructure
Wind
CCGTs
Trans-
Formers
Urban &
Rural
Cabels
North &
South
Network
design
Line rating
Network
Resilience
Climatology
for demand
forecasting
2010| 2020| 2030| 2040| 2050| 2060| 2070|
Climate change adaptation guide for Energy Phase 2 project
19. Hiatus in warming: Possible contributions
Met Office Hiatus report (IPCC AR5 will contain synthesised results)
http://www.metoffice.gov.uk/research/news/recent-pause-in-warming
• Natural variability: models have 10-15 year periods with no
warming or even cooling
• Incoming radiation: reduction of 0.6 Wm-2 needed to explain
pause. Maximum possible is 0.3 Wm-2
• Recent decrease in stratospheric water vapour: traps less heat: up to
0.1Wm-2
• Change in man-made aerosols: little net effect
• Volcanic eruptions: not enough during period
• Extended solar minimum: less than 0.2Wm-2
• Ocean changes: could be a major contributor
• Ocean heat content, sea-level rise observations: Earth system continued
to absorbed heat
• Additional heat appears to have been absorbed in the ocean.
• Increased exchange to deep ocean appears to have caused at least part
of the pause in surface warming,
• Observations indicate that Pacific Ocean may play a key role.
22. Climate model projections CMIP5
Preciptation (single study, AR5 will contain synthesised results)
Knutti and Sedláček, 2013
December - February
June - August
Stippling – high robustness
Hatching – no significant change
White – models inconsistent
Editor's Notes
The science of climate change is developing continually and raising important new issues and challenges.There are increasing demands for climate information on all timescales from months to decades. The Met Office is responding by establishing the UK Climate Service.
The Representative Concentration Pathways (RCPs) define feasible future pathways of greenhouse gas and aerosol concentrations and radiative forcing. They are based on Integrated Assessment Model simulations. RCP 8.5 is a high emissions scenario consistent with a high fossil fuel ‘business as usual’ future. RCP 2.6, which can be considered a world with a transition to a low carbon economy, has large and rapid reductions in man-made greenhouse gas emissions. They, along with intermediary RCP 4.5 and RCP 6.0, will form the future pathways used in the IPCC Fifth Assessment Report.
485 mm rainfall for Wales summer 2012Average – 270.6mmWettest June on record – 205mm (avg 86.2mm)
Alasdair Skea
Multi-model mean relative precipitation change for two seasons (December–February, DJF, and June–August, JJA) and one 20-year time periods centred around 2090, relative to 1986–2005, for CMIP5 (left) and CMIP3 (right). Stippling marks high robustness, hatching marks no significant change and white areas mark inconsistent model responses (