In a RCP6.0 world, some thoughts on climate change by 2100

Given current trends it seems that the RCP6 scenario will be the most realistic outcome of current development. This is more conservative than the 2  °C scenario much talked about in the press and at the Paris climate conference, with less ambitious efforts needed to achieve it. It still implies quite a bit of emissions reduction, especially after a supposed 2050 peak. (Emissions have to halve from the peak by 2100) It means that the  radiative forcing values in the year 2100 will be around 4.5 W/m2 if so. From here some likely projections can be made.

  1. Global sea levels will be, on average, 32 to 63 cm higher than in the year 2000. So Florida will still be around, mostly. Some very low Pacific islands may disappear if no sea walls are constructed. The Dutch will probably need to increase their walls a bit.
  2. Average temperatures above the jet stream in the northern hemisphere will increase from 3 °C to 5 °C above the 20th century average. Toronto for example will probably be 3 °C to 4 °C hotter by 2100 than it was in the 20th century. So approximately the current climate of Denver with severer winters. And Denver in 2100 will be like present day Austin, TX with colder winters. Austin will probably become too hot to live in without air conditioning in the summer.
  3. Coastal cities beyond the tropics will see around a 2 °C to 3 °C average increase.
  4. The good news is that coastal cities in the tropics will still be habitable, with only an average increase of 1 °C to 2 °C. Thought they will become more unpleasant outdoors, and air conditioning will become used in the summer even at night.
  5. Inland cities in the tropics however will likely need air conditioning 24/7 for at least the summer to be comfortable, due to an average increase of 3 °C to 5  °C. And walking outdoors during the day may become unbearable without special clothing and arrangements, like Bedouins in the present day sand deserts such as the Sahara. Most of inland India would fall into this category.
  6. Increasing desertification unless counteracted by ’green walls’, etc.
  7. Ice caps will melt by a significant amount, though the north pole will likely have a bit of ice cover remaining.
  8. Some of the higher altitude glaciers in the tropics, such as the Himalayas and Andes will still be around, though much reduced in size. Marginal glaciers will likely all disappear.
  9. Impacts on marine life, vegetation, and land animals are not yet understood well enough to say.
  10. Certain areas of the world will likely see significantly visual changes, though other places will see quite little change. Large chunks of Miami are likely to disappear without a seawall for example, though continental inland areas will just be warmer.
  11. Measurable negative effects of CO2 on human performance begins at 600 ppm. The RCP6 scenario means global average CO2 at 670 ppm, with cities more around 700 ppm, and indoors likely 800+


The Pacific Ocean is a great mirror, and all those who gaze across it see, not a true image of the other side, but an image mixed with their own reflections

To extend the analogy, many errant reflections from surrounding mirrors, objects, and other gazers in the field of view, intrude as well.

Is it then any wonder there are misunderstandings, confused perceptions, and bewildered gazers on both sides of the Pacific?

That’s my attempt at creating the best analogy to describe the situation of humans on Earth in our present age.

Complaints about the education of the youth from 1076 by Su Shi

I thought this was an amusing paragraph expressing the writer’s frustration at the mores and practices of the youth of 1076 in China.

I can recall meeting older scholars, long ago, who said that when they were young they had a hard time getting their hands on a copy of Shiji [Records of the Grand Historian] or Han shu [History of the Former Han]. If they were lucky enough to get one, they thought nothing of copying the entire text out by hand, so they could recite it day and night. In recent years merchants engrave and print all manner of books belonging to the hundred schools, and produce ten thousand pages a day. With books so readily available, you would think that students’ writing and scholarship would be many times better than what they were in earlier generations. Yet, to the contrary, young men and examination candidates leave their books tied shut and never look at them, preferring to amuse themselves with baseless chatter. Why is this?

Su Shi

The difference arose due to the proliferation of movable wood block printing in the 1000’s in Song dynasty China.

And curious indeed when comparing to our modern age.