I'm not keen on encouraging indexing for this type of operation. It can make brittle code that fails silently or unexpectedly. How about using coord_categorisation here to add a year coord? e.g.
```python
import iris.coord_categorisation

iris.coord_categorisation.add_year(temperatures, 'time')
time_mean = temperatures.collapsed('time', iris.analysis.MEAN)
anomaly = temperatures - time_mean

year = 1982
specific_year_anomoly = anomolies.extract(iris.Constraint(year=year))
```
It's a simple opportunity to demonstrate and encourage this approach. You can then use ```year``` and ```time_mean.coord('year').bounds[0]``` to get the values for the title.