Comparing Relationship Between Two Time Series (rainfall and discharge)

[brant]

Hi. I'm wondering if there are any hydrologists out there that could provide me with some advice. I have two time series datasets: daily precipitation and daily peak discharge. Both datasets span from the year 2000 until 2022. I am trying to model the correlation between daily precipitation and change in daily peak discharge (from the previous day). I want to be able to see if the effect size of the relationship between daily precipitation and change in daily peak discharge from 2000 to 2013 differs from the effect size of the relationship between precipitation and change in daily peak discharge from 2018 to 2022. Does anyone have any advice on how I can test this?

Thanks in advance.

The csv I have uploaded is formatted as follows:

Date, PeakDischarge, Precipitation, DailyChange

I want to be able to compare the strength of the relationship between "Precipitation" and "DailyChange" during both time periods (2000 to 2013) and (2018 to 2022) to see if it differs between time periods. Does anyone have any advice/guidance on this?

Thanks in advance.

[technocrat]

For each period, using daily peak discharge as v1, find the delta as v2 with

v2 <- diff(v1)

which will get you the lagged series with a one-day offset, because there is nothing to calculate the change for the first day.

With daily precipitation create v3 and then apply aov