Climate change threatens bridges
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Started by wglassfo - Nov. 7, 2019, 11:01 p.m.

I just came across an article written by engineers reporting on a threat of climate change. Specifically steel expansion bridges which employee expansion joints to allow the steel to expand or contract according to temperature

We all know that steel will expand or contract, when temperature changes. This is why steel expansion bridges have an expansion space to allow steel to expand during periods of high heat. These open spaces [as we would understand them] are often clogged with foreign material 

This requires periodic maintanence to keep the space clear of foreign material, and also keep to a minimum the movement of transport vechicles which use these bridges

As the planet heats up, which it is, then more frequent maintanence will be required or the steel will buckle under higher heat then the bridge was designed to accomodate and if the space is not cleared of foreign material more frequently

Northern climates will need more maintance as the temperature will affect these bridges more than bridges built in southern climates which are designed for higher heat expansion

Thus in yrs to come, expect highway interuptions to become more frequent as climate change will require more traffic interuption as the maintance is carried out more often.

If the space is not sufficient to allow for higher heat expansion, then the steel beams or plates will buckle and the bridge will fail.

IA has some 5000 steel expansion bridges

Comments
By wglassfo - Nov. 7, 2019, 11:11 p.m.
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I failed to explain what I meant by a minimum of vechicles using a steel expansion bridge. It should have been a minimum or slower travel speed of vechicles will be able to use the bridge while work is being done on one lane

 We all know the frustration of having a lane closed due to work performed on a highway lane and traffic forced to use a reduced amount of lane space

By metmike - Nov. 8, 2019, 3:10 p.m.
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Thanks Wayne!


Here's an article that discussed this:

Climate-driven extreme weather is threatening old bridges with collapse

http://theconversation.com/climate-driven-extreme-weather-is-threatening-old-bridges-with-collapse-121458

metmike: There has been climate change and today's climate vs 100 years is a climate optimum for almost all of life on this greening planet. Benefits outweight negatives for life by a 10 to 1 margin. We can continue with the same slow rate of warming for another 100  years and conditions for most life will continue to improve.

However, bridges are not living creatures and weaker constructed ones in some areas are more vulnerable to heavier rains. Mainly, very old, historic bridges.

 One of the things that climate change has caused is heavier rains, because warmer air holds more moisture>

So yes, some bridges will be more vulnerable to damage, especially the older, eroded or poorly constructed ones.

What should the response be to this?

To answer that, let's pretend we could go back to the old climate and CO2 from a century ago. 1 deg. C cooler and 100 parts per million less CO2.

1 billion people on this planet would starve to death within 3  years because of the drop in crop production, most life would suffer more adversity, especially from cold.

So even if that was an option, its a dumb idea to decrease rains by something like 6%.

What about taking actions so we don't have even more beneficial warming at a cost of tens of trillions of dollars because that means even more rains?

That would only make sense if:

1. We could spend all that money and have more than the 0.1 deg. C temperature difference it might make.

2. If that difference was actually saving the planet.  Earth does not need to be saved from a climate optimum. 

So that leaves 1 obvious choice. Adaptation to the heavier rains. New bridges, of course are structurally sound. We should make a strong effort to reinforce very old bridges and structures, at a cost that is a very tiny fraction of the cost of, wasting our time trying to change the climate...........that  doesn't need changing.


By metmike - Nov. 8, 2019, 3:17 p.m.
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On this being a climate optimum..............of course it is. 

Every other time in human history, we viewed these current conditions as a climate optimum. EVERY TIME!


That is, until climate science was hijacked for the political agenda.

CO2 is still a beneficial gas in all fields of science, biology, zoology, agronomy, climate/meteorology.

Only in politics is it defined as pollution.


https://en.wikipedia.org/wiki/Holocene_climatic_optimum

Temperature variations during the Holocene from a collection of different reconstructions and their average. The most recent period is on the right, but the recent warming is only seen in the inset.


The Holocene Climate Optimum warm event consisted of increases of up to 4 °C near the North Pole (in one study, winter warming of 3 to 9 °C and summer of 2 to 6 °C in northern central Siberia).

Out of 140 sites across the western Arctic, there is clear evidence for conditions warmer than now at 120 sites. At 16 sites, where quantitative estimates have been obtained, local HTM temperatures were on average 1.6±0.8 °C higher than now.  Northwestern North America had peak warmth first, from 11,000 to 9,000 years ago, and the Laurentide Ice Sheet still chilled the continent.  Northeastern North America experienced peak warming 4,000 years later. Along the Arctic Coastal Plain in Alaska, there are indications of summer temperatures 2–3 °C warmer than present.[5] Research indicates that the Arctic had less sea ice than the present."


That's the authentic science about past warmings compared to today that you are not told about. 

By metmike - Nov. 8, 2019, 3:26 p.m.
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What happens in Winter?

It gets cold in the mid/high latitudes and almost all of life faces the most harsh, life threatening conditions of the year.

Some life will migrate south to a warmer place to survive. Some life will hibernate because there is almost no food. Most plants will go dormant to not be killed by the cold. Annuals all get killed.

Global warming the past 100 years is warming the coldest places during the coldest times of year the most.

How is that bad?