RealClimate

Climate science from climate scientists...

You are here: Home / Archives for Climate Science

Climate Science

The IPCC Sixth Assessment Report

by

Climate scientists are inordinately excited by the release of a new IPCC report (truth be told, that’s a bit odd – It’s a bit like bringing your end-of-(seven)-year project home and waiting anxiously to see how well it will be received). So, in an uncharacteristically enthusiastic burst of effort, we have a whole suite of posts on the report for you to read.

If/when we add some more commentary as we digest the details and we see how the report is being discussed, we’ll link it from here. Feel free to discuss general issues with the report in the comments here, and feel free to suggest further deep dives we might pursue.

Realclimate redesign

by

After more than 15 years with basically the same layout, the Realclimate website – while still functional – has become increasing anachronistic both in appearance and ‘under the hood’. In order to take advantage of more up to date web-site designs and new features that have been developed since the early 2000s (!), we need to upgrade the site, and while we are at it, update the theme and design, while maintaining an aesthetic link to the original.

With this post, we can reveal the new layout.

The differences are not related to content but to appearance – all of the material is still here – but the new layout is much fresher and includes much better support for people reading the site on their phones or iPads. We are using larger typefaces, cleaner menus and a more content-focused presentation for posts.

All of this is intended to improve the reader/commenter experience, but it’s inevitable that we have missed some aspects and/or some of the design features may be suboptimal for some. We will endeavor to fix any issues or problems that you find. So please comment below if you like it or hate it, if you find anything that’s broken or if you have any specific requests for tweaks. We’ll try and iterate over the next few days to get it right.

Thanks!

Unforced Variations: Aug 2021

by

This month is IPCC month – the Sixth Assessment Report from Working Group 1 is out on Monday August 9. We’ll have some detailed comments once it’s out, but in the meantime, feel free to speculate widely (always considering that IPCC is restricted to assessing existing literature…).

Open thread – please stick to climate science topics.

Climate adaptation should be based on robust regional climate information

by

Climate adaptation steams forward with an accelerated speed that can be seen through the Climate Adaptation Summit in January (see previous post), the ECCA 2021 in May/June, and the upcoming COP26. Recent extreme events may spur this development even further (see previous post about attribution of recent heatwaves). 

To aid climate adaptation, Europe’s Climate-Adapt programme provides a wealth of resources, such as guidance, case studies and videos. This is a good start, but a clear and transparent account on how to use the actual climate information for adaptation seems to be missing. How can projections of future heatwaves or extreme rainfall help practitioners, and how to interpret this kind of information? 

[Read more…] about Climate adaptation should be based on robust regional climate information

Rapid attribution of PNW heatwave

by

Summary: It was almost impossible for the temperatures seen recently in the Pacific North West heatwave to have occurred without global warming. And only improbable with it.

It’s been clear for at least a decade that global warming has been in general increasing the intensity of heat waves, with clear trends in observed maximum temperatures that match what climate models have been predicting. For the specific situation in the Pacific NorthWest at the end of June, we now have the first attribution analysis from the World Weather Attribution group – a consortium of climate experts from around the world working on extreme event attribution. Their preprint (Philip et al.) is available here.

Trends in Tmax globally
[Read more…] about Rapid attribution of PNW heatwave

Why is future sea level rise still so uncertain?

by

Three new papers in the last couple of weeks have each made separate claims about whether sea level rise from the loss of ice in West Antarctica is more or less than you might have thought last month and with more or less certainty. Each of these papers make good points, but anyone looking for coherent picture to emerge from all this work will be disappointed. To understand why, you need to know why sea level rise is such a hard problem in the first place, and appreciate how far we’ve come, but also how far we need to go.

[Read more…] about Why is future sea level rise still so uncertain?

Nenana Ice Classic 2021

by

And…. it’s that time again. The clock stopped on the Nenana ice classic this afternoon (April 30, 12:50pm AT). This is pretty much on trend and unsurprising given the relatively slightly cool winter in Alaska. The jackpot on offer this year was $233,591 but will likely be shared among several winners. This year’s ‘break up’ is a little odd, since the ice moved sufficiently to trigger the clock, but not enough to actually topple the tripod (which is still visible as this is being written (9pm ET) – Update 10:30pm ET: gone now though!). But, the rules are the rules…

Nenana Ice Classic break-up dates since 1917.

The trends in the break up date is about 8 days earlier per century (±4), estimated over the whole record, but substantially faster over the last 50 years (16 ± 12 days/century, 95% CI).

Other phenological records show similar trends, notably the longest cherry blossom record from Kyoto which dates back to 9th Century, and which had a record earliest peak bloom this year and a clear trend over the last few decades:

Kyoto Cherry Blossom trends (graph from Statista)

Feel free to link to your favorite such record in the comments…