Sustainability Math A Quantitative Literacy and Mathematics Resource for Instructors

The Ocean Cleanup article Forecasting Ocean Plastic Around The GLOBE: A Deep Dive Into Modeling The Garbage Patches by Axel Peytavin (2/12/2021) provides an excellent overview of modeling the movement of plastic to the main garbage patches in the oceans.

We are now ready to delve into the core of the dispersion model: the advection scheme . It revolves around a central differential equation that integrates all phenomena at stake to give an estimate of a particle velocity, or the plastic’s speed through water. Basically, our methods calculate the particle’s velocity at a given time with a formula and use it to estimate where the particle will be a few minutes later. We repeat this process over a long period of time to get a series of positions, i.e., a trajectory of where the plastic goes.

Interesting data storage needs:

As this process has to be repeated over years, the datasets containing wind and speeds all around the globe can take up a lot of space. For instance, the LLC4320 global circulation model uses no less than 5 petabytes of data to be stored. At The Ocean Cleanup, we often use HYCOM data for currents (illustrated below), and GFS for the wind; and our datasets require at least 1.5 terabytes to be stored.

There is an equation and animated graphs.

As an aside here is a page with interesting marine mammal facts: Expert Guide to the Most Interesting Marine Mammals on the Planet.

For NOAA’s Global Climate Report – January 2021:

The January 2021 global land and ocean surface temperature was 0.80°C (1.44°F) above the 20th century average and ranked as the seventh warmest January in the 142-year global records. January 2021 also marked the 45th consecutive January and the 433rd consecutive month with temperatures, at least nominally, above the 20th-century average.

Only 7th warmest but

The year began with a La Niña episode in the tropical Pacific Ocean that started in August 2020. The El Niño-Southern Oscillation (ENSO) can affect global temperatures. La Niña tends to cool global temperatures slightly, while El Niño tends to boost global temperatures. With a slightly cool start to the year, there is only a 2.9% chance of 2021 ending as the warmest year on record. However, there is an over 99% chance of the year ranking among the 10 warmest years on record.

and

According to NCEI’s regional analysis, North America, as a whole, had its second warmest January on record, with a temperature departure from average of +3.96°C (+7.13°F). This was only 0.10°C (0.18°F) shy of tying the record warm January set in 2006.

and

As a whole, about 5.93% of the world’s surface had a record-warm January temperature–the third highest January percentage since records began in 1951. Only Januarys of 2016 (15.73%) and 2020 (7.05%) had a higher percentage of record warm January temperatures. Meanwhile, much of northern Asia was at least 2.0°C (3.6°F) colder than average, in stark contrast to most of 2020, when the region was well above average.

As always the report is worth reading and the data in the graph is available.

The eia article EIA’s AEO2021 shows U.S. energy-related CO2 emissions rising after the mid-2030s by Perry Lindstrom and Kevin Nakolan (2/11/2021) provides the graph copied here.

EIA projects that U.S. energy-related CO2 emissions will increase in the latter years of the projection as a result of increasing economic growth that leads to growing industrial energy requirements. EIA projects energy use in transportation will increase as vehicle fuel efficiency plateaus in the mid-2020s and becomes outweighed by increases in vehicle travel demand.

There are links to data in the article.

The USC Center for Economic and Social Research has a page Understanding America Study with results of survey questions related to COVID-19. For example, here is a time series of the percent of individuals very or somewhat likely to get a vaccine by race (not exactly encouraging). There are numerous choices from their dropdown menu regarding perceptions, behaviors, and impacts of COVID-19. Some details about the site:

The USC Center for Economic and Social Research’s Understanding Coronavirus in America tracking survey is updated daily with the responses of members of our population-representative Understanding America Study. Each panel member is invited to respond on a pre-assigned day of the week every other week. Each data point represents a full sample of responses from the previous seven days*. The graphs are updated just after 3am PDT every day of the week.

Each graph has a link to download the data.

The Climage.gov article Climate Change: Global Sea Level by Rebecca Lindsey (1/25/2021) provides a nice overview of rising sea levels. It is easy to forget that thermal expansion of water is a significant contributor to sea level rise.

Global mean sea level has risen about 8–9 inches (21–24 centimeters) since 1880, with about a third of that coming in just the last two and a half decades. The rising water level is mostly due to a combination of meltwater from glaciers and ice sheets and thermal expansion of seawater as it warms.

To estimate how much of the observed sea level rise is due to thermal expansion, scientists measure sea surface temperature using moored and drifting buoys, satellites, and water samples collected by ships. Temperatures in the upper half of the ocean are measured by a global fleet of aquatic robots. Deeper temperatures are measured by instruments lowered from oceanographic research ships.

To estimate how much of the increase in sea level is due to actual mass transfer—the movement of water from land to ocean—scientists rely on a combination of direct measurements of melt rate and glacier elevation made during field surveys, and satellite-based measurements of tiny shifts in Earth’s gravity field. When water shifts from land to ocean, the increase in mass increases the strength of gravity over oceans by a small amount. From these gravity shifts, scientists estimate the amount of added water.

The are other graphs in the article and links to data (note the link at the end of the article).

The eia article Six states accounted for more than half of U.S. jet fuel consumption in 2019 by Mickey Francis (1/27/2021) provides the graph here. Now, this isn’t surprising as CA, TX, FL, and NY are the four most populous states in that order. IL comes in 6 and GA 8. The article essentially notes this in the last line here:

In 2019, more than half of the jet fuel consumed in the United States was consumed in California, Texas, Florida, New York, Illinois, and Georgia, according to the U.S. Energy Information Administration’s (EIA) State Energy Data System. These states are home to many of the nation’s busiest airports and headquarters for many of the largest U.S. airlines. The six states are also among the most populous, accounting for about 40% of the U.S. population in 2019.

These six states represent 40% of the population but use 53% of the jet fuel and so there is a discrepancy. What accounts for the difference? For example, these 6 states account for about 44% of the GDP in the U.S. (BEA page 6), which closes the gap some. A stats project in the making. The eia page has links to their data.

The U.S. Bureau of Labor Statistics posts the chart (partially) copied here and last updated Sept 2020. An initial look at the graph and we see that the top 5 each have a median pay higher than the median pay in the U.S. (about $35k), but this is based on growth rate. On the other hand, if we look at the number of jobs the top 5 here are predicted to create, Table 1.3 from the BLS, we get 152.2 thousand jobs.  The sixth job on this list, home health and personal care aides, has a below median pay but is predicted to create 1,159.5 thousand jobs. There are 30 jobs listed in table 1.3 and home health and personal care aides represents about 45% of predicted new jobs created on this table. One can download the data in table 1.3 in an xlsx file.

The Pew article, A record number of women are serving in the 117th Congress by Carrie Elizabeth Blanzina and Drew Desilver (1/15/2021) reports:

Counting both the House of Representatives and the Senate, 144 of 539 seats – or 27% – are held by women. That represents a 50% increase from the 96 women who were serving in the 112th Congress a decade ago, though it remains far below the female share of the overall U.S. population.

The stacked bar chart copied here may be nice to look at but it is really hard to compare the changes in Republican women. A downside of the stacked bar chart.

Our World in Data now has a vaccinations as part of their Coronavirus Pandemic Data Explorer. As you can see the U.S. is doing relatively well. Now, Israel is doing much better than anyone and they aren’t on the graph because it makes it hard to see the rest of the countries selected here. Kevin Drum noted this is his post today The US is Doing OK on COVID-19 Vaccinations. He notes (referencing roughly the same graph here):

Why do I keep posting charts like this? Because we’ve spent way too much time on doom and gloom about how incompetently we’ve rolled out the COVID-19 vaccine. With the well-known exception of Israel, we’re doing as well or better than anyone else. If we’re incompetent, then the entire world is incompetent.

You can download the data from the Our World in Data page.

In my last post we saw that December 2020 was only the eighth warmest December. So, how did 2020 fair overall?  From NOAA’s Global Climate Report – Annual 2020:

With a slightly cooler end to the year, the year 2020 secured the rank of second warmest year in the 141-year record, with a global land and ocean surface temperature departure from average of +0.98°C (+1.76°F). This value is only 0.02°C (0.04°F) shy of tying the record high value of +1.00°C (+1.80°F) set in 2016 and only 0.03°C (0.05°F) above the now third warmest year on record set in 2019. The seven warmest years in the 1880–2020 record have all occurred since 2014, while the 10 warmest years have occurred since 2005. The year 1998 is no longer among the 10 warmest years on record, currently ranking as the 11th warmest year in the 141-year record.

The report is lengthy and worth reading. I’ll not this in particular:

Ocean Heat Content (OHC) is essential for understanding and modeling global climate since > 90% of excess heat in the Earth’s system is absorbed by the ocean. Further, expansion due to increased ocean heat contributes to sea level rise. Change in OHC is calculated from the difference of observed temperature profiles from the long-term mean.

The annual global ocean heat content (OHC) for 2020 is relatively unchanged from 2019, previously the highest annual OHC on record: while the 0–700m OHC is slightly lower, the 0–2000m annual global OHC is slightly higher than in 2019. The six highest OHC have all occurred in the last six years (2015–20). During 2020, the heating was distributed throughout the world’s oceans, with higher rates of warming in the northern and southern Atlantic and in localized zones of the Pacific, Indian, and Southern Oceans.

The ocean heating is irrefutable and a key measure of the Earth’s energy imbalance: the excess greenhouse gases in the air trap more heat inside the climate system and drives global warming. More than 90% of the heat accumulates in the ocean because of its large heat capacity, and the other heating is manifested in warming the atmosphere, warming and drying land, and melting land and sea ice. There are no reasonable alternatives aside from the human emissions of heat-trapping gases (IPCC 2001, 2007, 2013, 2020; USGCRP 2017).

The time series data is available in the box on the top center of the page under Temperature Anomalies Time Series.