The document summarizes key findings from the Sixth Assessment Report of the Intergovernmental Panel on Climate Change (IPCC) Working Group I on the physical science basis of climate change for the European region. It finds that temperatures are rising across Europe faster than the global average and heat waves are increasing, while cold spells are decreasing. Precipitation patterns are changing with more heavy rainfall in northern Europe in winter and drying in the Mediterranean in summer. Sea level rise and coastal flooding are increasing, and snow and ice cover is declining at high altitudes and latitudes. Specific regional impacts are also discussed, such as increased flooding in northern and western Europe but decreased flooding and increased fire risk in eastern Europe. The combination of changes poses increased risks

1. SIXTH ASSESSMENT REPORT
Working Group I – The Physical Science Basis
9 August 2021
#ClimateReport #IPCC #IPCCAtlas
SIXTH ASSESSMENT REPORT
Working Group I – The Physical Science Basis
Climate change information for the impact and risk assessment in the
European region
Erika Coppola, Maialen Iturbide, Robert Vautard,
Christophe Cassou, Irina Gorodetskaya , Svitlana
Krakovska , Bart van den Hurk, José Manuel Gutiérrez
Christophe Cassou
CERFACS. Department: Global Change and Climate
Modelling Project

2. SIXTH ASSESSMENT REPORT
Working Group I – The Physical Science Basis
• General intro on European Climate Change and CID’s (guided by Factsheet Europe): Erika (10 minutes live)
• Importance of the WG1 climate information for WG2 assessment: Daniela (10 minutes live)
• Intro and brief demo of the Interactive Atlas: Maialen (10 minutes live)
Examples of regional assessments
• Eastern Europe : Svitlana (10 minutes live)
• High latitudes: Irina (10 minutes online)
Additional dedicated topics:
Event Attribution: a tribute to Geert Jan van Oldenborgh : Robert (10 minutes online)
Climate change and internal variability in Europe: Christophe (10 minutes online)
Break out groups to tackle Q&A’s on the topics above (approx 20 minutes):
• Guidance for CIDs and assessment (moderated by Erika and Bart)
• Interactive Atlas and Mediterranean climate change as showcase (moderated by Maialen, Jose and Jorge)
• Attribution (moderated by Robert and Richard)
• Internal variability (moderated by Christoph)
• High latitudes (moderated by Irina)
• Eastern Europe (moderated by Svitlana)
Session outline

3. SIXTH ASSESSMENT REPORT
Working Group I – The Physical Science Basis

4. SIXTH ASSESSMENT REPORT
Working Group I – The Physical Science Basis
New Concept

5. SIXTH ASSESSMENT REPORT
Working Group I – The Physical Science Basis
Common regional changes

6. SIXTH ASSESSMENT REPORT
Working Group I – The Physical Science Basis
• Regardless of future levels of global warming, temperatures will rise in all
European areas at a rate exceeding global mean temperature changes,
similar to past observations (high confidence).
• The frequency and intensity of hot extremes, including marine
heatwaves, have increased in recent decades and are projected to keep
increasing regardless of the greenhouse gas emissions scenario. Critical
thresholds relevant for ecosystems and humans are projected to be
exceeded for global warming of 2°C and higher (high confidence).
• The frequency of cold spells and frost days will decrease under all the
greenhouse gas emissions scenarios in this report and all time horizons,
similar to past observations. (high confidence)
• Despite strong internal variability, observed trends in European mean and
extreme temperatures cannot be explained without accounting for
anthropogenic factors. Before the 1980s, warming by greenhouse gases
was partly offset by anthropogenic aerosol emissions. Reduced aerosol
influence in the recent decades has led to an observable positive trend in
shortwave radiation. (high confidence)
Heat and cold

7. SIXTH ASSESSMENT REPORT
Working Group I – The Physical Science Basis
• Observations have a seasonal and regional pattern consistent with projected
increase of precipitation in winter in Northern Europe.
• A precipitation decrease is projected in summer in the Mediterranean
extending to northward regions.
• Extreme precipitation and pluvial flooding are projected to increase at global
warming levels exceeding 1.5°C in all regions except the Mediterranean. (high
confidence)
Precipitation

8. SIXTH ASSESSMENT REPORT
Working Group I – The Physical Science Basis
• Regardless of level of global warming, relative sea level will rise in all European areas except the Baltic Sea, at a rate close to or
exceeding global mean sea level. Changes are projected to continue beyond 2100. Extreme sea level events will become more
frequent and more intense, leading to more coastal flooding. Shorelines along sandy coasts will retreat throughout the 21st century
(high confidence).
• Strong declines in glaciers, permafrost, snow cover extent, and snow seasonal duration at high latitudes/altitudes are
observed and will continue in a warming world (high confidence).
Coastal
Snow and ice
• Multiple climatic impact-drivers have already changed concurrently over recent decades. The number of climatic impact-driver
changes is expected to increase with increasing global warming (high confidence).
Multiple climatic impact-drivers

9. SIXTH ASSESSMENT REPORT
Working Group I – The Physical Science Basis
Sub-regional specificities

10. SIXTH ASSESSMENT REPORT
Working Group I – The Physical Science Basis
Northern Europe (NEU)
• Observed increase in
pluvial flooding attributed
to human influence and
projected to further
increase at global warming
of 1.5°C (medium
confidence) and 2°C and
above (high confidence).
• Projected decrease in river
flood at global warming of
2°C and above (medium
confidence).
• Projected increase in
severe wind storms at
global warming of 2°C and
above (medium
confidence).
Change in river discharge per unit catchment
area corresponding to the return period of 100
years for the mid-21st century
drought indicator
m3 s-1 km-2

11. SIXTH ASSESSMENT REPORT
Working Group I – The Physical Science Basis
Western & Central Europe
(WCE)
• Projected increase in
pluvial flooding at global
warming of 1.5°C (medium
confidence) and 2°C and
above (high confidence).
• Observed increasing trend
in river flooding and
projected further increase at
2°C and above of global
warming (high confidence).
• Projected increases in
hydrological, agricultural
and ecological droughts at
mid-century warming levels
of 2°C or above, regardless
of the greenhouse gas
emissions scenario (medium
confidence).
drought indicator
Change in river discharge per unit catchment
area corresponding to the return period of 100
years for the mid-21st century
m3 s-1 km-2

12. SIXTH ASSESSMENT REPORT
Working Group I – The Physical Science Basis
Eastern Europe (EEU)
• Projected increase in
pluvial flooding at
global warming of
1.5°C (medium
confidence) and 2°C
and above (high
confidence).
• Projected decrease in
river flood at global
warming of 2°C and
above (medium
confidence).
• Projected increase in
fire weather at global
warming of 2°C and
above (medium
confidence).
drought indicator
Change in river discharge per unit catchment
area corresponding to the return period of 100
years for the mid-21st century
m3 s-1 km-2

13. SIXTH ASSESSMENT REPORT
Working Group I – The Physical Science Basis
Mediterranean (MED)
• Observed increase in
hydrological and
agricultural and ecological
droughts (medium
confidence), projected
increase in aridity and fire
weather conditions at global
warming of 2°C and above
(high confidence).
• Projected combination of
climatic impact-driver
changes (warming,
temperature extremes,
increase in droughts and
aridity, precipitation
decrease, increase in fire
weather, mean and extreme
sea levels, snow cover
decrease, and wind speed
decrease) by mid-century and
at global warming of at least
2°C and above (high
confidence).
drought indicator
Change in river discharge per unit catchment
area corresponding to the return period of 100
years for the mid-21st century
m3 s-1 km-2

14. SIXTH ASSESSMENT REPORT
Working Group I – The Physical Science Basis
Regional Synthesis TS4

15. SIXTH ASSESSMENT REPORT
Working Group I – The Physical Science Basis
Regional Synthesis IA
EU
With further global warming, every region is projected to increasingly experience
concurrent and multiple changes in climatic impact-drivers. Changes in several climatic
impact-drivers would be more widespread at 2°C compared to 1.5°C global warming
and even more widespread and/or pronounced for higher warming levels. {SPM C.2}

16. SIXTH ASSESSMENT REPORT
Working Group I – The Physical Science Basis
9 August 2021
#ClimateReport #IPCC
SIXTH ASSESSMENT REPORT
Working Group I – The Physical Science Basis
@IPCC
@IPCC_CH
linkedin.com/company/ipcc
IPCC: www.ipcc.ch
Interactive Atlas: interactive-atlas.ipcc.ch
Follow Us: