Titanic and Global Warming15 April 2012
After the RMS Titanic’s collision with an iceberg a century ago today, the passengers did not believe the ocean liner would sink. The ship was so gargantuan and stably designed it showed few outward signs of being in imminent danger, and took 2 hours and 40 minutes to sink. But sink it did. The Earth’s climate is rather like the Titanic: an enormous beast that is deceptively stable and slow to respond to disturbances.
The parallels between global warming and the Titanic disaster begin before the collision, with the failure to heed iceberg warnings. If you’ll forgive me for quoting Wikipedia:
The North Atlantic liners prioritised time-keeping above all other considerations, sticking rigidly to a schedule that would guarantee their arrival at an advertised time. They were constantly driven at close to their full speed, treating hazard warnings as advisories rather than calls to action. It was widely believed that ice posed little risk […] Titanic‘s future captain, Edward Smith, declared in an interview that he could not “imagine any condition which would cause a ship to founder. Modern shipbuilding has gone beyond that.”
In the case of global warming, the scientists warned us decades ago there might be icebergs in our path, but these warnings were ignored, seen by the world’s captains as merely advice from an interest group, drowned out by the advice of powerful industries to continue full steam ahead with our fossil fuel economy, obsessed with short-term profit at any cost. The belief that ice was no longer a threat to ships is reminiscent of the confidence of today’s leaders that environmental damage does not threaten our civilization – for example, the Australian Financial Review’s insistence this week that food security cannot possibly be an important issue in Australia.
The captain did not even receive the final and most urgent warnings: the owner of the ship, Bruce Ismay, was carrying around a telegram on the fateful day which he never bothered to deliver to the captain, apparently considering it unimportant. When an iceberg did loom out of the darkness at 11:40pm on 14 April 1912, the crew did not have time to adapt. They attempted to turn the ship, but were unable to avoid impact. The iceberg scraped along the side of the ship, buckling the hull and opening narrow gaps, many meters long but with a total area of only a square meter or so, through which water began to flow.
How were such relatively small holes able to sink the mighty Titanic? The key was not the size of the openings but their distribution. The lower part of the Titanic was divided into sixteen compartments. The ship could stay afloat if only four compartments flooded, but because it did not hit the iceberg head-on, five compartments were breached, so water was able to overflow into the rest of the ship. Similarly, the carbon dioxide which is the main driving force of human-caused global warming is often ridiculed as a trace gas comprising a mere 0.04% of the atmosphere, but the important factor is not its concentration but its heat-trapping properties. Although 99% of the Earth’s atmosphere is made of nitrogen and oxygen, those gases do not behave in the same way and thus are not as important to the climate.
The collision of the Titanic is different from the onset of climate change in an important way. One cannot pinpoint a single moment when we hit the iceberg; it is more like we are crashing in slow motion. Unlike the accumulation of water in the Titanic, the buildup of carbon dioxide began very gradually. I suppose one could argue it began with the invention of the steam engine in 1775, which allowed humans to start burning carbon at a significant and increasing rate, but that analogy does not strike me as very meaningful. I think there is a more useful metaphor: the collision represented the point at which sinking became inevitable.
The climate system contains tipping points, beyond which the climate change we started would spiral out of our control. A climate tipping point may be separated into two components: the “tipping level” (say, a certain increase in CO2) and the “point of no return”. For the Titanic, these two things occurred in the same instant: the ocean liner was doomed as soon as five compartments were breached; the pumps simply could not respond fast enough. However, the inertia in the climate system suggests that even if CO2 has passed the “tipping level”, climate change may not yet have reached the “point of no return”. Some scientists argue the tipping level for dangerous global warming is 350 ppm of CO2 in the atmosphere, which we sailed past around 1990. But the point when dangerous global warming becomes inevitable, we hope, still lies ahead of us, albeit drawing closer every year we fail to take action.
There is another way the Titanic’s collision can be compared to climate change. Although it was instantaneous rather than gradual, the collision was barely noticed by passengers, who felt only a slight shudder. Yet an informed person in the boiler rooms would have been able to see the water flooding into more compartments than the ship could withstand. If the Earth is an ocean liner, then its boiler room is the Arctic Ocean. It is the fastest-warming place on Earth, and so is suffering the worst impacts. At the recent Planet Under Pressure conference, Tim Lenton argued the Arctic is approaching a tipping point, beyond which it will flip to an sea-ice-free state. That would in turn dramatically decrease the reflectivity of the Arctic surface, further accelerating global warming and particularly the melting of the Greenland ice sheet.
Aware of the situation in the boiler rooms, the Titanic’s builder Thomas Andrews informed the captain the ship would sink within 1-2 hours. The captain ordered the lifeboats to be uncovered, passengers to be brought up on deck, and distress signals to be sent. However, similarly to our planet’s leaders, the captain failed to adequately communicate the severity of the crisis by not giving the order to “abandon ship”. Again from Wikipedia:
Smith was an experienced sailor who had served for 40 years at sea, with 27 years in command. He would certainly have known that even if the boats were fully occupied, a thousand people would remain on the ship as she went down. As the enormity of what was about to happen sank in, he appears to have become paralysed by indecision. He did not issue a general call for evacuation, failed to order his officers to load the lifeboats, did not adequately organise the crew, withheld crucial information from his officers and crewmen, and gave sometimes ambiguous and impractical orders. Even some of his bridge officers were unaware for some time after the collision that the ship was sinking; Fourth Officer Joseph Boxhall did not find out until 01:15, barely an hour before the ship went down, while Quartermaster George Rowe was so unaware of the emergency that after the evacuation had started, he phoned the bridge from his watch station to ask why he had just seen a lifeboat go past.
The Titanic had only a slight list, the electricity was kept running until its final minutes, and the ship’s band played music to calm the passengers. Few realised the situation was serious:
Many passengers and crew were reluctant to comply [with the instruction to come on deck], either refusing to believe that there was a problem or preferring the warmth of the ship’s interior to the bitterly cold night air. The passengers were not told that the ship was sinking, though a few noticed that she was listing. Around 00:15, the stewards began ordering the passengers to put on their lifebelts, though again, many passengers treated the order as a joke. Some set about playing an impromptu game of football (soccer) with the ice chunks that were now strewn across the foredeck. […]
Similarly, global warming is happening gradually because it takes time for the extra heat which our emissions are trapping to work its way through the climate system, triggering feedbacks along the way, until it reaches a new equilibrium. For example, ocean currents take centuries to completely turn over.
Captain Smith continued to bungle the situation:
Smith did not advise his officers that the ship did not have enough lifeboats to save everyone. He did not supervise the loading of the lifeboats and seemingly made no effort to find out if his orders were being followed. […]
By about 00:20, 40 minutes after the collision, the loading of the lifeboats was under way, though it was perhaps symptomatic of Captain Smith’s apparent indecisiveness that it was at the suggestion of Second Officer Lightoller. As the latter recalled afterwards, “I yelled at the top of my voice, ‘Hadn’t we better get the women and children into the boats, sir?’ He heard me and nodded reply.” Smith ordered Lightoller to put the “women and children in and lower away”. Lightoller took charge of the boats on the port side and Murdoch took those on the starboard side. The two officers interpreted the evacuation order differently; Murdoch took it to mean women and children first while Lightoller thought it meant women and children only. Lightoller lowered lifeboats with empty seats if there were no women and children waiting to board, while Murdoch allowed a limited number of men to board if all the nearby women and children had embarked. Neither officer knew how many people could safely be carried in the boats as they were lowered and erred on the side of caution by not filling them. They could have been lowered quite safely with their full complement of 68 people. Had this been done, an extra 500 people could have been saved; instead, hundreds of people, predominantly men, were left on board as lifeboats were launched with many seats empty.
Titanic had more lifeboats than were required by regulations. Its owners had not bothered to provide enough boats for all the passengers, because they would have cluttered the deck. Today’s fossil fuel companies are similarly not breaking the law by digging up and burning billions of tonnes of fossil carbon, and they fiercely protest against any laws to restrict this activity.
Even if there had been enough lifeboats and the crew had handled the situation better, many passengers were reluctant to leave the apparent safety of the ship to board them:
When the crew began asking them to climb aboard the lifeboats, most didn’t believe it necessary. As Edwina Mackenzie, then Edwina Troutt, one of the survivors, recalled in a 1975 BBC interview, ‘You could not get people to go on lifeboats, you could not. They felt safer on the Titanic than in the lifeboats.’
Another survivor, a Major F.W. Prentice, interviewed by the BBC in 1966 said, ‘The first boats that got away were only half-filled … nobody realised then that she would sink, you know. She was supposed to be unsinkable, absolutely. She had a double bottom …’
And Commander Lightoller, interviewed in 1936 stated, ‘Up to the time of getting away the first few boats, no-one believed that the ship was actually in any danger. I’m afraid my own confidence that she wouldn’t or couldn’t sink rather conveyed itself to others, for there were actually cases where women absolutely refused to be put in a boat.’
Eva Hart in a 1983 BBC interview stated, ‘In fact, I believe some people did go back to bed. But he (my father) said, “Stay here and I’ll see if I can find one of the officers,” and away he went again. And he came back and said, “They are going to launch the boats, purely a precaution. You will all be back on board for breakfast.”‘
The first lifeboat was launched a full hour after the collision – demonstrating the social inertia in responding to the crisis:
J. Bruce Ismay, realising the need for urgency, roamed the starboard deck and urged passengers and crew to evacuate. A trickle of women, couples and single men were persuaded to board starboard lifeboat No. 7, which became the first lifeboat to be lowered.
As the third-class passengers were in the lower part of the Titanic, the disaster affected the poorest first and worst, though ultimately it affected everyone on the ship. As their quarters flooded, third-class passengers had to find their way through a maze of corridors to get up on deck. There were barriers between third-class and second-class levels of the ship, and the crew had locked some of them (there is controversy about whether there was deliberate intent to prevent third-class passengers from reaching the lifeboats). Some made it to the deck, but others did not even attempt to, remaining to pray or perhaps awaiting orders.
Global warming is somewhat similar in that the poorest are tending to feel its effects hardest, partly because they happen to be in the wrong place at the wrong time, and partly because they have less capacity to adapt. (We could argue about which events can be attributed to global warming, but there are obvious physical reasons why warming would be causing more floods and droughts, sea level rise, etcetera.) Eventually, of course, if we allow the Earth to warm several degrees, no corner of it will be safe.
It was not until the last hour that the passengers on deck began to panic. The boats were loaded more quickly and with more people; the wireless messages became ever more desperate. After the last lifeboat was launched at 2:05am, the captain declared “every man for himself”.
Throughout the first 2 hours and 20 minutes, more than half of the ship was above water. But of course, the ocean liner did sink, and when the point of collapse finally came it happened quickly. After the forecastle disappeared beneath the waves around 2am, it only took about 20 minutes for the entire ship to be totally submerged. In Titanic’s last few minutes, as water flooded in from the top, the ship’s angle increased rapidly and its front half was submerged, causing the ship to split in two and the lights to go out; then as the stern flooded it rapidly went vertical, causing large numbers of passengers to fall into the water, and finally plunged into the ocean at 2:20am. A collapse of global civilization would also likely occur relatively suddenly, after the gradual worsening of environmental problems.
Unlike Titanic, our Earth is alone in the ocean of space. There are no lifeboats, no other spaceships to rescue us. But also unlike Titanic, we still have time to avert a catastrophe.
Whereas Titanic flooded 15 times faster than its pumps could cope with, the Earth still has natural sinks which are removing carbon dioxide from the atmosphere (and in the future we may be able to capture some artificially). We still have a narrow window in which, if we can cut global fossil fuel emissions to zero or near-zero fast enough, we should be able to bring CO2 back below the tipping level of 350 ppm. This means we must replace fossil fuels with renewable energy technologies. I am optimistic this is possible. Thus if the Titanic represents not the Earth but our fossil-fuelled economy, one could say renewable energy sources are our lifeboats.
However, if we wait too long, CO2 will climb too high to reverse, or the carbon sinks will warm up enough that they cease to absorb our CO2 and instead emit more of it (among other nasty feedbacks). The latest science suggests we have about two decades, maybe three. Just as Titanic’s builder gave a time limit for when the ship would sink, the Earth’s scientists have given us a rough time limit for how long we have to limit global warming to a manageable level.
Our economy is sinking, and so far we have done little more than rearrange the deckchairs. It’s time to heed the warning from the Earth’s boiler rooms and get into the lifeboats.
This post was partly inspired by Ockham’s Razor, 17 April 2011, “The Titanic Disaster and Global Warming”.