Oceans and seas

Kids enjoying the sea off Bubble Beach, Dominica

After talking about the atmosphere I briefly turn to the oceans and seas. The atmosphere would have a lot more CO2 and be a lot hotter if the deep water covering 70% of the planet hadn’t absorbed huge amounts of both. We are not funding enough research into the impacts on global warming. And because ocean research is expensive scientists don’t know as much as they would like. But we know enough to understand the broad impacts. I will mention a few aspects relevant to those on the front lines – islands and coastal communities.

Sea level rise

Imperceptible to me, but Grand Anse is retreating with the rising sea and will eventually be lost

Sea levels are rising with the melting of our land based ice fields. Greenland and Antarctica are the two major ones. There is enough ice on Greenland to raise sea level by 20 feet and 10 times that amount around the south pole. Oceans are rising because of the meltwater and because water expands as it warms.

From Micheal Mann, but several website use this or similar graphs

The average annual increase in oceans levels between 1900 and 1930 was about 0.02 inches per year. The annual average rate then more than doubled to 0.05 inches until 1993. After 1993 the rate more than doubled again to 0.13 inches per year. Since 2015 the annual rate is now about 0.18 inches. Still, a lot of ice remains on land. It’s not good that it seems like we’ve already past a couple of small tipping points and the rate of change might follow an exponential rather than linear pattern.

Sea level is a rising concern in many places. Some Pacific islands formed by corals are returning to the seas and displacing communities and nations. Volcanic islands like the Hawaiian islands, Grenada, and Dominica are taller, but much of the infrastructure and tourist attractions are on the level ground near sea level, such as airports, beaches, and coast roadways.

Coastal countries, such as Bangladesh, are already also suffering. Coastal cities in the US are not immune to the global rise. Millions will suffer and be displaced in this (as yet still) slow moving problem. I hope most can somehow adapt and respond but I don’t see practical methods to prevent loss of coastline and infrastructure in developing countries other than moving and better long term planning. I’m not going to retire to southern Florida in any event.

Heat - Storms

Photograph by Peter Swarzenski (USGS)

https://www.usgs.gov/media/images/flooding-sorlie-bridge

Warmer oceans mean that more water can evaporate and warmer air can hold more moisture. This leads to heavier rains with more flooding and soil erosion. Tropical Storm Erika in 2015 is a recent Caribbean example. You don’t need a hurricane to cause massive destruction and death.

These storms represent a clear danger today. There might be little warning so action must be taken before the storms to prevent the worse damage.

Heat and acidification – ocean life

Healthy (Coral reef - public domain)

Warmer oceans aren’t able to hold as much oxygen as cooler waters which is bad enough for most life. But the absorbed CO2 is reducing the ocean pH from around 8.1 towards 7.8. As the oceans move from a base toward neutral the calcium carbonate structures needed by many ocean life forms are harder to form. These factors stress life starting at the bottom of the food chain with phytoplankton and moves all the way up.

Most phytoplankton are plants. They are not only vital in the ocean food web but might account for half of the CO2 absorbed by photosynthesis on the planet. We can see the destruction of major forests but it is much harder to notice the 40% decrease in phytoplankton.

Not healthy (https://www.usgs.gov/media/images/fire-coral-bleaching)

We depend on the oceans for life and the foundation of the food chain is dying away. Island nations and coastal communities rely on the oceans for food and employment. Life will be harder with degraded fisheries. Quality of life and tourism also suffers when coral reefs die and beaches disappear. Degraded ocean life is a problem we have to face. A full scale collapse of ocean life system is a long way off and should be avoided at all costs.

So much to learn about

Global warming is very complicated and I’ve touched on only the very tip top of the iceberg. I’ve chosen topics I think are relevant to my current Peace Corps assignment. If I was in the gulf coast the dead zone from agricultural runoff would be more important. If I was in Bangladesh I would put more emphasis on sea level rise and salination of farmland. Rain patterns and heat would be primary concerns in the Upper West of Ghana.

I hope these past few weeks have been interesting and that you will do your own research with scientific publications or accurate mainstream reporting. Pick topics that interest you personally. Look around and see how global warming is changing your area and how you want to react. People in Nebraska, and their climate denier governor, might be more interested in heavy rains and flooding than sea level rise. And on and on.

Afterwards, look for things you can do to either reduce the problem or to make yourself, your family, and your community more resilient to our shared future. Certainly citizens in industrial countries can work for policy change that might save the planet. Focused boycotts, demonstrations, and other political actions can change policy. Local small activities can lead to national and global impacts – just ask a young Swedish girl who sat outside her parliament.

There are many activities people in non-industrial countries, such as those served by Peace Corps, can do to improve the quality of life and increase resiliency on our warming planet. Some actions will also reduce the level of greenhouse gas as a bonus.

My future posts will include to some practical responses that volunteers and others might try. If you have ideas in this regard it would be great to tell me, greater if you tried to put them into practice, and wonderful if you spread the word to others. We are all in this together.

Field trip

On Friday the school went on a field trip to Mt. Carmel falls and Grand Etang lake. It was nice to get out with the kids, even though I had to remind them about littering a few times.