UV App revived
.... and the 'Geeks' mode for the GlobalUV app explained.
Sorry about the typos in the e-mailed version my last offering. Get the Substack App (freely available for both Android and iPhone) to see versions of my posts with corrections and updates. Back-postings are readily findable. Also avoids losing posts in spam folders.
Some of you may have noticed that for a short time last month, the UVNZ smartphone app that produces UVI information for New Zealand was not operating correctly. We know some noticed, but hopefully not too many, because the glitch occurred in winter when UV levels are low, so the risk of harm is small.
The data displayed in the app comes courtesy of a NIWA data server. Unfortunately, NIWA decided in July to make some changes in data formatting, which tripped up the code to read it. My friend Jerry was able to quickly fix the Android version, but the iPhone version took a little longer because of Apple’s draconian developer’s quagmire.
Both are now fixed. If you don’t have automatic app updates enabled on your phone, your current version may still look wrong. If so, go to the app store for a free update. Hopefully, the new version will be more robust and immune to future data formatting changes.
The GlobalUV app, which calculates the daily progression of UVI anywhere on the globe, was not affected and has continued to run reliably since we introduced it four years ago. It calculates the UVI on the fly from input fields of ozone, cloud transmission, and aerosol optical depth. Even if those data feeds are not available, it still provides realistic estimates of clear-sky UV from an ozone climatology. GlobalUV (note: no spaces there) is limited by its use of cloud transmission data only for local solar noon (to keep the size of data transfers manageable). It then assumes that cloud transmission at noon persists throughout the day. By contrast, UVNZ includes shorter term cloud effects.
On the subject of GlobalUV, I’d like to point out nice educational feature that you may not have stumbled across. It can be found under the ‘Geeks’ sub menu item (accessible from top left of the main screen on the iPhone version).
A sample screen-shot is shown below. It allows you to see both the temporal changes in UVI over a day at any location (graph at top), and the spatial pattern of UVI over the globe at that time (map below). The site selected here - see the black dots on each image - was Cairns, Australia, as accessed that day from my iPhone in New Zealand at 16:10 NZST (i.e., 14:10 in Cairns).
In the map, you an see that the peak UVI at that time occurs to the north west of Cairns - roughly over the equator - for this late afternoon period near the spring equinox. The controls at the bottom also allow you to investigate the effect of seasonal changes (by month), and of selectable changes in ozone. Everything you always needed to know in one handy package!
Both apps include behavioural advice on skin damage protection and vitamin D production, each of which depends on selectable skin type. The latter also depends on selectable clothing attire. UVNZ has the endorsement of the Cancer Society of New Zealand (and since the messaging in GlobalUV is the same, I’m sure they’d be happy to endorse that as well).
Finally, these changes at NIWA had one further benefit. They motivated my colleagues there to add similar functionalities into the NIWA weather app. I’d tried for years before my ‘retirement’ in 2012 to get somebody there to this, before giving up and persuading Jerry to do it. The NIWA version is not yet as good as Jerry’s apps but is a lot better than it was (and even has tidal information). Hopefully, it will continue to be supported long after Jerry and I have moved to greener pastures.