England and Wales Rainfall

In 2016 I posted about UK rainfall and found that by the measure used the probability of a very wet year had increased in recent decades to 3/6 from a prior frequency of 1/6. In this post I revisit that work using an improved demarcation for wet and very wet.

What I have now found is a change of precipitation around 1998, before which the joint probability of a wet or extreme wet year has now risen from 18% prior to 1998 to 58%, a three-fold risk increase, in line with my 2016 work. 

This is a substantial change with serious implications for human impacts such as flooding.

2015 Record Temperature

As you already know 2015 was the warmest year on record in the instrumental record, at an anomaly of 0.87degC this is a substantial new record. Anyway, for what it's worth, here are a few comments and graphs (late because I've been too busy at work).

Is Prince Charles Correct?

In an interview recorded before the recent Paris massacre Prince Charles has recently told Sky News that he thinks that Climate Change is one causal factor in the ongoing Syrian situation. Rejecting him out of hand does not seem sound to me based on the available evidence.

UK H2O

Tamino has recently posted a summary of the drought situation in California. Frankly if I lived there and read that post (or read the news!) I would be selling up and moving out before it gets worse. Anyway, now that I have finally got round to doing it, this seemed like a good excuse to finally get round to updating the UK rainfall plot.

Global and UK Temperatures 2014: New Records?

The BBC are reporting that this year looks set to be the warmest year across the globe and here in the UK. Although I mainly concentrate on the Arctic and sea ice, I couldn't do that without being all too aware of anthropogenic global warming, so here goes...

UK Wet Summers post 2007: How Unusual?

In my mid month miscellanea post earlier today I posted a list of the top ten wettest summers, four of those are years from 2007 to 2013. Just how odd is this?

Eurasian Snow Cover and Atmospheric Impacts

I've been looking again at the new summer atmospheric circulation pattern. In "The Recent Shift in Early Summer Arctic Atmospheric Circulation.", abstract, Overland et al identify the shift as an Arctic Dipole pattern. However as I have shown, and as Overland et al also state, this has wider impacts.

But is there a role for snow cover changes in driving this new pattern, and if so what is it?

Northern Hemisphere Blocking.

Over at Neven's Sea Ice Blog, Steve Bloom posted a link to some data on Northern Hemisphere blocking, I've got to work on the data Steve linked to, but haven't really got to the bottom of the matter. This data holds some exciting detail. I've not reached a firm conclusion on this, I need to read some more papers on blocking. But this post summarises where I've got to.

Drought again...

Due to events in the Arctic this will be a short post, no need to click 'more', there isn't any more.

Stuart Staniford, on his "Early Warning" blog, has done a typically excellent post on Aiguo Dai's latest paper, the post is here. I've previously blogged on the issue of drought and Hansen's Climate Dice, here and here. Dai's paper is published around the same time as Hansen's Climate Dice new paper is also published, that's discussed here, the actual paper is available here. It's basically a re-run of the Climate Dice whitepaper Hansen released last November, this time peer reviewed and published.

Aiguo Dai's paper, "Increasing Drought under Global Warming in Observations and Models" is available here, that link brings up an html version of the paper for me - no paywall. It revisits earlier work and finds that the lack of drought signature in the US had been due to climatic variability, specifically the Pacific Interdecadal Oscillation, as that impact is now reducing and the warming is continuing, the match between models and observations this century has improved. But rather than me re-produce Stuart's post go read it.

Actually, it strikes me that Al Qaeda have been following the wrong path all along. Instead of suicide bombings, the way to destroy the USA would be to set up an Islamic theocracy somewhere where there's loads of oil, get the US addicted to it by selling it for less than it's really worth, and let the climate system do the hard work. Hang on...

CO2's role in the end of the Last Glacial

A recent paper by Shakun et al may throw new light upon the role of CO2 in the past glacial and interglacial periods. What does it mean, and does it change the situation we face with regards the current era of anthropogenic global warming, driven in large part by human emissions of CO2?

Mid January Miscellanea.

Arctic Sea-Ice in the Little Ice Age.

A recent paper by Kinnard et al examines the history of sea-ice using proxy data and recent observations. It really puts what's been going on recently in context and is another brick in the wall of evidence showing that current events in the Arctic are so unusual that they demand explanation and cannot simply be dismissed as being down to natural factors when anthropogenic warming is an ongoing process. Skeptical Science have covered Kinnard et al, now Tamino has a good post with an observation I was going to comment on over there, but it could do with some expanding. And as I have a blog...

Into the Hot Zone.

On Friday the IPCC released the draft version of their new report: Special Report on Managing the Risks of Extreme Events and Disasters to Advance Climate Change Adaptation (SREX) PDF. The report relased is merely the Summary for Policy Makers (SPM), the full scientific basis report will not be released until early 2012. Much of the text concerns vulnerability and exposure to the risks of climate change, although there is a shallow but useful summary of the observations and projections related to climate extremes. RealClimate have already done a post on the findings related to Tropical Storms. I'm not going to go over SREX in great detail but a few points from it relate to the recent Hansen paper discussed in my previous post.

Hansen's Climate Dice.

I'm facing another battle with scepticism. Previously when I was a sceptic of Anthropogenic Global Warming (AGW) I just wasn't thinking critically. Now I think I'm thinking more critically, and the battle I face now is with the issue; Just how bad is AGW going to be?

Matters arising from D'Aleo 3: The 1940s and the present.

The warming of the 1940s was not like the current warming. There are differences in observations and the model evidence supports the idea that while the 1940s was an outcome of natural variability, whereas the recent warming is externally forced.

Matters Arising from D'Aleo 2: The AMO & PDO.

Regarding the Atlantic Multi-decadal Oscillation (AMO). D'Aleo claims it "Looks like an awfully good fit. There is very little, if any, global warming." I've already pointed the following out to him. The Center for Atmospheric Research suggests that the major part of recent ocean warming in the AMO is due to global warming, once the global warming signature is removed the AMO is rather a small effect. So that source suggests that if warmer ocean waters due to the AMO are substantially responsible for loss of Arctic sea-ice, then it is global warming that is causing most of the warming.

Cooling of the Arctic Stratosphere since 2007

In comments on my earlier post "Arctic Dipole: A Positive Feedback" Kevin O'Neill raised an intriguing point regarding stratospheric cooling and tropospheric warming in the post 2007 period during the summer (June - August).He also pointing out that there was a mixed picture previously, see here. Kevin's graphic is here.

This has had me puzzling over it for the last few days, so yet again the posts I was going to do on the recent cold winters will be delayed. However I think I now have a reasonable explanation for the observations Kevin raised.

Cool wet summer.

Here in the UK we've had another cool wet summer dominated by low pressure systems. UK temperature is notably very variable, this is due to our location and the interplay of weather systems. We're in the battleground between continental European, and maritime Atlantic air masses, at the end of the Jetstream's path across the Atlantic.
Unfortunately the NCEP/NCAR interface doesn't allow me to compare a string of years seasonally, and looking for any changes in the summer weather needs to be seasonally based (by definition). However there is a publicly available dataset that does allow me to look at temperatures, the world's longest instrumental temperature series, the Central England Temperature series (CET).

The loss of multi-year sea ice, Part 1.

There are two types of sea-ice in the Arctic, first-year (FY) and multi-year (MY). It's been known for some time that MY sea ice is in decline.

Here is an NSIDC graphic of the series of James Maslanik.