What will be the climate change effect?

What will be the climate change effect? This is a bit like asking 'how long is a piece of string' because the effect could be large, widespread and catastrophic— as some of the politicians and activists would have us believe.

Or it could be small, local and a nudge to the environmental system, well within its capacity to cope.

Small or large depends on how much the climate will change, how rapidly it changes and where you happen to be on the planet.

Consequently, the specifics are hard to pin down. There is considerable uncertainty around the detail.

What we do know is that climate is changing and this means that

• local and global weather patterns will be different to those in the past
• oceans will change their volume and pattern of circulation with implications for sea level and the weather on coasts and islands
• glaciers will retreat and advance
• snow cover will change its extent and persistence with direct effects on meltwater and the earth’s albedo

And all this is normal and to be expected.

Think of it like this.

Climate has changed continually throughout the earth’s history.

Any long-term view would see temperatures range wide enough to turn a polar desert into a hot one and the amount of rainfall vary enough to turn arid plains into wet forests. 

So the conundrum is not that change happens, it is what change brings with it that concerns us.

When the climate changes, or more exactly when the pattern of weather is consistently out of the ordinary, nature must respond to the new conditions. Each plant and animal from bears to tiny ameoba in the soil, must respond to the new temperature and moisture regime.

And for all the plants and animals that make up the natural systems there will be one of three outcomes, organisms will:

1. survive or prosper under the new conditions
2. move away if the conditions don’t suit 
3. die out if the new conditions are stressful and the move away option is blocked

If world weather changes fast or with such intensity that survival and movement are compromised for more than a handful of organisms the capability of nature to function is compromised.

More importantly this is the same nature that drives agriculture and a host of other environmental services that 7 billion people rely on. 

This is the critical unknown for the climate change effect — how much it will impact on the services that humans need.

Specific climate change effects

The list of specific effects will be long.

Here is the climate change wisdom compilation, not exhaustive and presented in no special order and with links to more details:

• changes to ocean currents
• melting glaciers
• change in frequency and intensity of wild fires
• size, shape and thickness of ice caps
• ocean acidification
• severe weather events including severe storms and cyclones
• drought
• sea surface temperature changes
• snow cover
• desertification
• rising sea levels

Some of these effects are events – wild fires, severe weather, drought – that will change in their intensity or frequency depending on where you are in the world.

Others are more pervasive across time and/or space – ocean currents, ocean acidification, snow cover, rising sea levels - and these will have both direct and knock on consequences for nature.

The most serious are the effects that generate positive feedback, where the effect has itself an impact on climate change, especially on global warming:

• methane release form melting permafrost peat bogs (arctic methane release)
• methane release from hydrates
• carbon cycle changes
• forest fires
• retreat of sea ice through the ice-albedo feedback
• sulfer cycle

Hold on a minute. These are all physical effects.

Without realizing it we have lapsed into the objective speak of the scientist and honed in on to climate change effect in the physical and biological world.

There will also be a climate change effect on human economic and social systems.

Human health, migration patterns, economic development, agriculture, insurance, transport infrastructure will all be different as a result of a changing climate.

Why? Because our social and economic systems, if not always our wealth, are still tied very closely to how the environment performs for us.

Climate change will affect how easy is it to

• grow crops
• herd stock
• produce timber
• find a place to live and
• to move around the place

and can be made easier or harder by the weather and its patterns.

The physical factors may have dominated debate on the climate change effect; but it is the social and the economic effects that will determine the real consequences.

the real effect

When all is said and done, climate change, that most natural of things that has defined planet earth for 4,500 million years, is a human issue… a species from a lineage that has been around for less than 0.07% of that time.

0.07% is less than one minute of a 24 hour day