Sea levels in the Pacific

I recently visited Port Vila, capital of the Pacific island nation of Vanuatu (the photo above is from the Port Vila waterfront). Port Vila is the site of a sea-level measuring station. It is interesting that, although local newspapers are deeply concerned about sea level rise, the average sea level rise between 1993 and 2017 at Port Vila was essentially zero (see chart below, which uses LOESS smoothing of monthly measurements).

How can this be? Aren’t global sea levels rising at 2–3 mm per year? Well, “global sea level” is a rather theoretical concept. Ocean temperatures are not uniform. Some islands are rising out of the ocean. Others are sinking. Air pressure, and the El Niño Southern Oscillation cycle, have a huge effect on sea levels too. As they say, it’s complicated.

The NASA map below shows that some areas of the Pacific have actually seen a long-term reduction in sea level (independent of any upward or downward movement of land). Other areas, of course, have seen quite rapid increases (the increases and decreases average out to a rise of about 3 mm per year). The map covers data only up to 2008, however. Since 2008 was roughly the peak for the Port Vila data, it doesn’t quite explain the last decade of the graph above. If I had to guess, I’d assume that some of those sea-level-decrease areas on the map had shifted a bit.


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New solar car teams #5: Appalachian State

It’s a bit of a stretch calling Appalachian State University / Sunergy  (click: ) a new solar car team. Having rebuilt the shell of an old car donated by PrISUm, they first hit the American solar car scene at FSGP 2015 (where they failed scrutineering), ASC 2016 (where they came 6th), and FSGP 2017 (where they came a satisfying 2nd). But this year they did become a new team (in the Cruiser class), with their first car built from scratch, ROSE.


AppState’s ROSE (picture credit)

The Cruiser class is, in some ways, a tougher race than the Challenger class, but it’s an easier sell (to sponsors and to the general public). For example, I’m a big fan of Nuon’s beautiful and efficient Nuna 9S (the Stradivarius of solar cars), but you can’t really point to it and say “this is the future of transportation.” It’s far too cramped for that – more like an elegant mathematical proof or a work of art than like a practical vehicle. However, “the future of transportation” would be a feasible label for Cruisers like Eindhoven’s Stella Lux or Bochum’s SunRiser – so it’s not surprising that many solar car teams want to emulate those two pioneers.


The Stradivarius of solar cars, from Dutch champions Nuon, is nevertheless a little cramped (picture credit)

AppState did the right thing by attending ASC 2018, although their car had apparently not even been turned on before the race. Because of electrical problems, they did not manage to drive the entire distance – but they obtained good experience, and they know what to fix now. We can expect to see a greatly improved version of their car at the 2019 Bridgestone World Solar Challenge. Good luck, y’all!

AppState’s multi-stage path to the BWSC is a good model for other intending Cruiser class teams to follow. And with a drag coefficient of 0.17, they have not made the mistake of neglecting aerodynamics – because, in the Cruiser class, efficiency still rules.


New solar car teams #4: ATN

ATN Solar Car Team  (click: ) is a new Australian Cruiser-class solar car team. They are attempting something I have never seen done before – design and construction of a solar car by a team distributed across a continent. According to the initial press release:

I will be very interested to see if they can make this work and which virtual team tools and techniques they will use to do so. So far, ATN Solar Car Team has produced a number of quite different design concepts. The video below shows one of the more interesting ones, and has produced many admiring comments:

Note: Independently of this effort, the experienced Team Arrow will continue as a Cruiser-class team based in Brisbane (also associated with QUT).


New solar car teams #3: Chalmers University

Chalmers Solar Team  (click: ), from Gothenburg, is one of two new Swedish solar car teams (both in the Challenger class, as are the existing teams from Jönköping University and Mälardalens University). Their preliminary render (above) is reminiscent of the South African Naledi (from NWU), but this render seems to date from before the start of serious design work, so we might see something quite different for the race. Lycka till!


The team is housed next to the campus library (photo: Bjoertvedt)


Support for Kavanaugh vs support for Trump

Brett Kavanaugh has been in the news rather a lot lately. The chart above shows support for his appointment to the US Supreme Court, for various demographic groups, as per a 1 October Quinnipiac University Poll. This is compared to the 2016 Trump vote for those same groups, as per CNN exit polls (in both cases, some missing information had to be inferred using the data provided plus census data). The area of the circles shows the size of the various groups.

Responses to Kavanaugh seemed largely to follow partisan lines. Democrats mostly went one way, Republicans the other. However, white women seemed to support Kavanaugh less than expected, perhaps because they were more likely to believe the accusations made against him. Minority groups, on the other hand, were more supportive of Kavanaugh than of Trump, perhaps because of concerns about evidence, corroboration, and due process. Overall, it seems to almost balance out, though – I must say that I can’t see any support here for a “blue wave” at the November elections.


New solar car teams #2: Halmstad University

Halmstad University Solar Team  (click: ), from Halmstad, is one of two new Swedish solar car teams (both in the Challenger class, as are the existing teams from Jönköping University and Mälardalens University). Their university is relatively new, having been established in 1983. It sees itself as “innovation driven,” which makes building solar cars a good fit for them. HUST is still refining their design, but they seem to be influenced by Michigan’s 2017 “bullet car.” They are also fundraising on gofundme to raise support for their solar car construction and travel to Australia. Lycka till!


New solar car teams #1: Top Dutch

Top Dutch Solar Racing  (click: ) is a new solar car team sponsored by the northern (“top”) region of the Netherlands: the provinces Groningen, Friesland, and Drenthe (see topdutch.com). This is a region with a long history and a strong environmental focus (see montage above).

The team is associated with the Hanze University of Applied Sciences, the University of Groningen, the NHL Stenden University of Applied Sciences, and local high schools. They are building a Challenger-class car for the 2019 Bridgestone World Solar Challenge. Although I wasn’t aware of it at the time, they had observers at the 2017 event, so they know what they are up against. They will be joining three other teams from the Netherlands (Nuon, Twente, and the Cruiser-class team from Eindhoven), which means that, for the first time, an all-Dutch podium becomes a possibility.

Team manager Jeroen Brattinga explains the project in this (Dutch) video. They have also been driving a test chassis around for some time.