I tend to disagree that John Howard invented the term El Nino , it has been known of for the last 10,000 years.
Known about in scientific circles for a long time certainly but the general public seems to have only recently become aware of it.
I mentioned it at a public meeting about 20 years ago in the context of drought in Australia. Would have been a few hundred people in that room and every single one of them had a blank look on their faces. In contrast, these days I think most would at least recognise the terms and know that El Nino is associated with drought in parts of Australia.
Today, we're in that same place with the Indian Ocean Dipole. Another cycle that has an impact in Australia, in some areas it's actually more significant than El Nino / La Nina, but there's relatively little public knowledge about the IOD thus far.
ENSO conditions have occurred at two- to seven-year intervals for at least the past 300 years, but most of them have been weak.
Another factor with the impact is the intensity of resource use.
If you go back to pre-1950 then to a very large extent we made no effort to utilise an entire natural resource. We built a dam on a river to supply a town with water, but the town only used a few % of the available water and the rest went down the spillway. The impact of drought was less water going down the river but it had no impact on the town's water supply unless it came to the point of the river literally drying up.
Much the same with agriculture in Australia. We had more than enough land and most of it unused so it wasn't overly difficult to just scale up farming as needed.
Same with hydro power. We've been generating power from the South Esk River (Tas) since 1895, so that's 120 years, but it wasn't until 1955 that sufficient capacity was installed to use the full non-flood flow of the river. So pre-1955, any variation in water flow affected how much water
didn't go through Duck Reach power station but had no effect on the power station itself (well, OK, the 1929 flood disaster wrecked the plant and a lot of other things, including many lives lost, but that's another story).
Past - we went to whatever land or river and used a bit of what was available to supply the needs of the time.
Today - we use the whole lot apart from any land or water set aside for reasons of maintaining the natural environment.
So modern society, whilst in some ways seemingly insulated from weather (big cities, global distribution of food etc), is actually more sensitive to weather variation than in the past to the extent that that variation leads to reductions in water availability (for whatever purpose) or food production.