Yes, that is the L root server and if you look at the weeks range by Node you can see that it has a lot heavier load over the last day and a bit as well, it starts spiking at the end of the 28th.
The spike is in IPv4 traffic for A type queries.
What is interesting is that it appears to be from two subnets responsible.
The 18.104.22.168 subnet (country code AU) as that has gone from a mean query rate of 300 q/s (a week ago) to 1500 q/s this week
The 22.214.171.124 subnet (country code IN) has gone from about 300 q/s to 900 q/s
Also the recursion desired has gone from less than 1000 to just under 4000.