The second of the most intense pair of heat waves ever to roll across the European continent is now departing Scandinavia and headed for Iceland and Greenland where it will finally dissipate altogether. On account of these unprecedented bursts of heat, the weather record book has been rewritten across much of Europe. All-time national heat records were set in Belgium (41.8°C/107°F), France (46.0°C/115°F), Germany (42.6°C/109°F), Luxembourg (39.0°C/102°F), and the Netherlands (40.7°C/105°F). A provisional record of 38.7°C/102°F was established in the United Kingdom and is currently under review for verification. Norway had an all-time record-tying 35.6°C/96°F temperature. Paris' Parc de Montsouris, where records go back to 1872, recorded a 42.6°C/109° all-time record. Helsinki (Kaisaniemi), where records go back to 1844, reached an all-time record of 33.2°C/92°F. Prior to 2019, Germany had never registered a 40.0°C or above temperature. At the height of the European furnace on July 25, 25 German cities reached or exceeded 40.0°C.
Although both air masses had origins in northern Africa, ongoing climate change played a critical role in driving the outcome. The historic heat demonstrated that the findings of an enormous and growing body of climate science research are not only valid, but also that the implications of climate change are verifying in remarkable fashion.
On that topic, a paper published just last year explained:
Previous European assessments have shown that the number of heat-waves in Europe is projected to increase, with greater increases expected in southern Europe...
Heat-waves were defined as three consecutive days where both the maximum and the minimum temperature exceed their respective 95th percentile from the historical period. All calculations were done for May to September...
We have analysed 50 climate model projections from the CMIP5 (RCP8.5) ensemble and calculated consistent and comparable metrics of climate impacts for HW, droughts and flooding for 571 European cities. More frequent and hotter HW are expected for all European cities. Southern cities see the largest increase in the number of HW days (as much as 69%).
To date, the fastest warming has been taking place in the Arctic. As a result, average annual sea ice extent and the summer minimum extent have generally been declining. During the 1990-99 period, average annual Arctic sea ice extent was 11.443 million square kilometers and the average minimum extent was 6.492 million square kilometers. During the 2010-2018 period, the average annual extent was 10.330 million square kilometers and the average annual minimum was 4.330 million square kilometers. In short, the average annual figure has fallen by nearly 10% while the average annual minimum has fallen by around one-third meaning larger summer melts and slower winter recovery.
What is happening in the Arctic has far broader implications. The combination of the resulting Arctic Amplification (AA) and dramatic slowing of the Atlantic Meridional Overturning Current (AMOC) has favored the development of patterns that can bring brutal heat to Europe.
A paper published in Nature explained:
Recent studies indicate that the Atlantic Meridional Overturning Circulation (AMOC, i.e., the large-scale north-south transport in the Atlantic ocean) has seen an unprecedented slowdown in recent decades, something which is projected for future warmer climates as well. This slowdown results in anomalously cold SSTs over the northern Atlantic which can trigger a quasi-stationary Rossby wave response favoring blocking high-pressure systems over western Europe. So, just like AA, a slowdown of the AMOC leads to weakening westerlies in summer over the Atlantic sector, favoring persistent hot-dry extremes over Europe. Recent observational studies indeed indicate that weather persistence in Europe and some other mid-latitude regions has increased in boreal summer.
At this stage, as most Europeans know based on the repeated results of opinion polls, the scientific evidence for climate change with anthropogenic fossil fuel emissions being the principal driver is all but unequivocal. Residual uncertainties exist, but the overall foundation of the science is highly robust. No credible counterargument based on internal variability or solar cycles exists, as the global temperature trend has decoupled from these natural variables.
On a global basis, the last colder than normal month was September 1992 with an anomaly of 0.01°C below normal. Through June 2019, the last 225 months have all been warmer than normal. The last colder than normal year was 1976 with a global anomaly of 0.10°C below normal.
The recent historic European heat waves are the latest symptoms of climate change. Relief is coming. Nevertheless, climate science research warns that the frequency and intensity of such heat could continue to grow in coming decades.
12 comments
Stormlizard said:
Don Sutherland replied to Stormlizard:
In my view, it is an important topic, especially as "science denialism" remains entrenched and maintains disproportionate influence over public policy in some areas (less so in Europe). This attitude is not honest scientific skepticism.
A recent paper published in Nature Human Behavior distinguishes between scientific skepticism and the "science denialism" being advanced to mislead the public about climate change.
Science denialism must not be confused with scepticism. Scepticism towards scientific propositions is a crucial element of science itself. In fact, it functions as a driving force of scientific debates and increases the quality of new propositions via mechanisms such as peer review and the replication of experimental research. The common ground of this functional scepticism is the scientific ethos that scientists use data to update their prior beliefs regardless of the outcome. However, in contrast to functional scepticism, science deniers accept evidence only if it confirms their prior beliefs--that usually contradict the scientific consensus. This dysfunctional scepticism is driven by how the denier would like things to be rather than what he has evidence for, making science denialism a motivated rejection of science.
t.co/jysNBwsVA2
Stormlizard replied to :
I see things here that have never before been seen so far north, animals, birds, insects and plants which is absolute proof of the changing climate.
Don Sutherland said:
A recording of 38.7°C at Cambridge Botanic Garden on Thursday 25 July has become the highest temperature officially recorded in the UK.
The provisional value was released on Friday and has been subject to quality control and analysis over the past few days. It has now been validated by the Met Office observations’ team.
This figure exceeds the previous record of 38.5°C recorded in Faversham, Kent, in August 2003.
www.metoffice.gov.uk/about-us/press-office/news/weather-and-climate/2019/new-official-highest-temperature-in-uk-confirmed
Andy Rodker said:
Nonetheless, you provide some interesting data, Don and whilst I have been a semi-sceptic, never a denier, I am slowly falling into line. Why was I a sceptic? Simply because my history studies revealed variations from century to century anyway, often caused by increased volcanic activity and so on, at least within the last 10,000 years or so of (amazing) stability.
Don Sutherland replied to Andy Rodker:
You most definitely don't qualify as a "denialist" or "denier. There's a difference between honest skepticism and denial. One who is skeptical allows oneself to be guided by the evidence and, in the process, reassesses one's opinion as warranted. The latter refuses to accept the evidence or any other information that might challenge his or her position no matter how unsustainable that position might be.
Don Sutherland replied to :
Don Sutherland said:
rmets.onlinelibrary.wiley.com/doi/epdf/10.1002/joc.6213
LutzP said:
aNNa schramm said:
greetings aNNa*
Don Sutherland replied to aNNa schramm:
Don Sutherland said: