The Mpemba Effect . . .

. . . . is incredibly counter-intuitive.

First, some context. The following chart shows the cooling behaviour that most people would expect from two identical containers of water that start at different temperatures; the cooler sample (the blue line) would reach zero degrees first (Time #1) and turn to ice (Time #2) before the warmer sample (the red line).

TypicalProfile

The Mpemba effect says that sometimes the warmer water freezes first! Continue reading The Mpemba Effect . . .

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Crunching the numbers of the 1984 Election

In a previous blog post I took exception to the media’s characterization of the Liberal victory in the 2015 federal election as ‘stunning’ and ‘decisive’ (link). It occurred to me afterwards that it would be interesting to compare this Liberal victory with the Conservative victory of 1984, which the media also characterized as ‘stunning’ (link).

Spoiler: The Conservative victory in 1984 was seventeen times more stunning and decisive than the Liberal victory in 2015!

Continue reading Crunching the numbers of the 1984 Election

Crunching the numbers of the 2015 Election

In October 2015 the liberals won 184 seats in the Canadian Parliament of 338 seats. The CBC called it a “decisive majority” (link). The National Post wrote that the Liberals “steamrolled to a stunning majority victory” (link). From my perspective, those conclusions seem hyperbolic.

Continue reading Crunching the numbers of the 2015 Election

Dendroclimatology in my sideyard!

An opportunity to investigate the value of using tree rings to measure relatively long-term temperature trends almost fell into my lap a couple of weeks ago; a windstorm blew down my neighbour’s tree. It was about forty years old, seventy feet high and on the north side of my house. The trunk is around 30 inches across at the base and the tree rings were clearly visible. I measured its tree ring widths for the last twenty complete years (1997-2016), and correlated it with the maximum annual temperature in Ottawa (link) of those years. Fascinating!

Continue reading Dendroclimatology in my sideyard!