It looks like you're new here. If you want to get involved, click one of these buttons!

- All Categories 2.3K
- Chat 500
- Study Groups 19
- Petri Nets 9
- Epidemiology 4
- Leaf Modeling 1
- Review Sections 9
- MIT 2020: Programming with Categories 51
- MIT 2020: Lectures 20
- MIT 2020: Exercises 25
- MIT 2019: Applied Category Theory 339
- MIT 2019: Lectures 79
- MIT 2019: Exercises 149
- MIT 2019: Chat 50
- UCR ACT Seminar 4
- General 69
- Azimuth Code Project 110
- Statistical methods 4
- Drafts 2
- Math Syntax Demos 15
- Wiki - Latest Changes 3
- Strategy 113
- Azimuth Project 1.1K
- - Spam 1
- News and Information 148
- Azimuth Blog 149
- - Conventions and Policies 21
- - Questions 43
- Azimuth Wiki 713

Options

I've started a wiki entry:

that explains this index. It's a famous way to tell if an El Niño is happening.

## Comments

The NOAA data is at 2.5 degree intervals, so you get 5N, 2.5N, 0, 2.5S, 5S. Are the 5N and 5S counted as in or out?

`The NOAA data is at 2.5 degree intervals, so you get 5N, 2.5N, 0, 2.5S, 5S. Are the 5N and 5S counted as in or out?`

Ugh, I can't tell! At least, not yet. All I see is that

I don't know whether they count grid points that lie right on the boundary of a rectangle as part of that rectangle!

`> Are the 5N and 5S counted as in or out? Ugh, I can't tell! At least, not yet. All I see is that > The Niño 3.4 region spans a swath from 5°N to 5°S latitude and 120°W to 170°W longitude. I don't know whether they count grid points that lie right on the boundary of a rectangle as part of that rectangle!`