alternative to interpolation, how to introduce randomness

Hello, I have a vector of 8760 values, representing hourly solar irradiance per one year. I need the irradiance "per second" (so moving to 31536000 values). I can do it by interpolation but is a quite rough method, too approximated. I want to introduce some randomness. Ideas?

[Walter Roberson]

I do not understand the reference to 31.5 ?

[Nicolò Monaco]

Sorry, I made a mistake. I meant 31536000 values which are secods in a year.

[Jonas]

what about using interp() and then just adding some randomness by addition or subtraction?

Answer 1

[Walter Roberson]

d = rand(3600, length(flux_per_hour));
rd = d./sum(d,1);

flux_per_second = flux_per_hour(:).' .* rd;   %seconds down, hours across
flux_per_second = flux_per_second(:);         %consecutive seconds

[Nicolò Monaco]

good method, thank you