Mike James wrote:
Could someone enlighten me as to why the days continue to grow shorter
after the solstice?

They don't. Sunrise continues to get slightly later for a while yet, but
overall, the days start lengthening.
--
Steve Loft
Sanday, Orkney. 5m ASL. http://sanday.org.uk/weather
Free weather station softwa http://sandaysoft.com/
uk.sci.weather FAQs/glossary/etc: http://weatherfaqs.org.uk/