---
title: "CO2 Keeling"
author: "David Elser"
date: "05-03-2021"
output: html_document
---
## Data preprocessing fetch the Data file and check if file already exists

The data is available from the  Web site of the Scripps Institute "https://scrippsco2.ucsd.edu/data/atmospheric_co2/primary_mlo_co2_record.html"

Soure script available at : https://github.com/DemirhanOzelTrojan/Keeling_Predict/blob/master/main.R
install.packages('forecast', dependencies = TRUE)
install.packages("imputeTS")

```{r}

install.packages("imputeTS")
library(forecast)
library(imputeTS)
```


```{r}
data_url = "https://scrippsco2.ucsd.edu/assets/data/atmospheric/stations/in_situ_co2/monthly/monthly_in_situ_co2_mlo.csv"
data_file = "CO2.csv"

if (!file.exists(data_file)) {
    download.file(data_url, data_file, method="auto")
}
```

Skip the frist 5 lines of the file

```{r}
data = read.csv(data_file, header=TRUE, skip=5)
```

Let's have a look at what we got:
```{r}
head(data)
tail(data)
```


```{r}
data$X.ppm.[data$X.ppm. == -99.99] <- NA
data$X.ppm. <- na.interpolation(data$X.ppm.)
head(data)
tail(data)
```