About two months ago I had the post How low is Lake Mead? The graph in the post was the yearly minimum end of month elevation. In this post we have a closer look at the end of month elevation since 2011. The last month in the data is July 2021, which is a record low following the previous record low in June 2021. In the previous post I mentioned that this really should be given in some per capita format. I’ll add that presumably the decrease in the volume of water is not linear with the lake elevation. Data here.
The graph below shows the number of days per year that sea level in Kings Point, NY is projected to exceed 60 cm above MHHW.
Sea level rise will increase the likelihood of tidal flooding. NASA has posted a tool, Flooding Days Projection Tool, to help understand how much tidal flooding may increase. There is a drop down menu for numerous locations in the U.S. For example, the graph here is for Kings Point, NY. Along with the value of the data there are calculus terms in the post:
These projections are based on unique, location-specific relationships between annual mean sea level, the top 1% of astronomical tides in each year, and annual counts of threshold exceedances.
An interesting and essential feature of these graphs is that the number of flooding days per year does not necessarily increase smoothly in time. In most cases, there are inflection points where the frequency of flooding days increases rapidly, which may be useful when establishing planning horizons. In many locations around the United States and its territories, there are sharp inflection points around the mid-2030s that are related to the interaction between accelerating sea level rise due to climate change and a long-term, 18.6-year cycle in the amplitude of astronomical tides.
And discussions of probabilistic modeling:
The purpose of this tool is to produce probablistic projections of flood frequency in the future that provide information about the full range of possibilities for a given year, including the potential for the occasional—yet inevitable—severe years. The projections leverage the predictability inherent in certain contributions (e.g., tidal amplitude and climate-change-induced sea level rise) and use statistical methods to account for everything else. The projections are probabilistic, because rather than producing a single, most-likely number of flooding days for a future year, these projections produce a range of plausible numbers with probabilities assigned to each possibility or range of possibilities.
All in all this is a great resources for math classrooms.
Have you wondered if your state just had the hottest, driest, wettest, etc. month? You can get this information from NOAA’s Statewide Ranking page. For example, the graphic here is for California for July 2021. The output will provide ranking information for 1-12, 18, 24, 36, 48, and 60-month time periods. The 1, 2, 3, 4, and 5 month periods ending in July 2021 have been the hottest on record going back 127 years. The page allows users to select a state and various periods. Each output also has a link to the data. An overview and definitions of these ranking is given on the Climatological Rankings page.
As a whole, the July 2021 global surface temperature was the highest for July since global records began in 1880 at 0.93°C (1.67°F) above the 20th-century average of 15.8°C (60.4°F). This value surpassed the previous record set in 2016 (and subsequently matched in 2019 and 2020) by only 0.01°C (0.02°F). Because July is the warmest month of the year from a climatological perspective, July 2021 was more likely than not the warmest month on record for the globe since 1880. Nine of the 10 warmest Julys have occurred since 2010, with the last seven Julys (2015-2021) being the seven warmest Julys on record.
The data is available at the top of the page under Additional Resources.
The IPCC sixth assessment report was just released. The graph here is from the summary for policymakers. The 42 page summary could be used as part of a sustainability or QL type course as there are plenty of graphs. Page 15 starts the discussion on the different scenarios, which is an opportunity to talk about modeling and assumptions. For a sense of the long term consequences:
In the longer term, sea level is committed to rise for centuries to millennia due to continuing deep ocean warming and ice sheet melt, and will remain elevated for thousands of years (high confidence). Over the next 2000 years, global mean sea level will rise by about 2 to 3 m if warming is limited to 1.5°C, 2 to 6 m if limited to 2°C and 19 to 22 m with 5°C of warming, and it will continue to rise over subsequent millennia (low confidence). Projections of multi-millennial global mean sea level rise are consistent with reconstructed levels during past warm climate periods: likely 5–10 m higher than today around 125,000 years ago, when global temperatures were very likely 0.5°C–1.5°C higher than 1850–1900; and very likely 5–25 m higher roughly 3 million years ago, when global temperatures were 2.5°C–4°C higher (medium confidence).
Looking back even farther by using a drought indicator known as the Standardized Precipitation Index, the current drought in Arizona is also the worst on record back to the late 1800s. Going back even farther than THAT by using tree rings across the Southwest as stand-ins for soil moisture, the current drought over the entire region is one of a handful of the worst droughts in the last 1200 years. Other especially bad droughts occurred in the late 1500s and late 1200s (known as the Great Drought). Basically, this is a long-winded way of saying the current drought in Arizona and the Southwest is bad no matter if you look back 10 years, 100 years, or 1,000 years.
The graph copied here shows that it has been 6 years since a wet year with 2020 precipitation the lowest since 1900. And, of course:
According to the Climate Science Special Report, temperatures across the Southwest have increased by 1.61 degrees Fahrenheit since the first half of the 20th century. These increases in temperature contribute to aridification in the Southwest by increasing evapotranspiration, lowering soil moisture, reducing snow cover and impacting snowmelt.
Looking to the future, temperatures in the Southwest are projected to increase by the end of the century by around 5 degrees Fahrenheit if carbon dioxide emissions follow a lower path and up to 9 degrees if emissions follow a much higher path. Increasing temperatures can make soils even drier, amplifying drought.
There are other graph in the article but no direct links to data. Still, there is good information and plenty of material for a QL course.
The June 2021 global surface temperature was the fifth highest for June in the 142-year record at 0.88°C (1.58°F) above the 20th century average. Only Junes of 2015 (fourth warmest), 2016 (second warmest), 2019 (warmest), and 2020 (third warmest) were warmer and had a global temperature departure above +0.90°C (+1.62°F). Nine of the 10 warmest Junes have occurred since 2010.
But June seemed hot you say? Yup:
The global land-only surface temperature for June 2021 was the highest on record at 1.42°C (2.56°F) above average. This value surpassed the previous record set in 2019 by +0.11°C (+0.20°F). The ten warmest June global land-only surface temperatures have occurred since 2010. The unusually warm June global land-only surface temperature was mainly driven by the very warm Northern Hemisphere land, which also had its highest June temperature departure at +1.69°C (+3.04°F). The now second highest June temperature for the Northern Hemisphere occurred in 2012 (+1.51°C / +2.72°F).
Time series data is available at the link near the top of the page.
Berkeley Earth summarizes the recent heatwave in the Pacific Northwest in the article The Pacific Northwest Heatwave in Context (7/6/2021). The graph by Dr. Robert Rohde copied here is striking and really says all that needs to be said. This is a graph that everyone should have to study and understand. This was anything but a typical heatwave.
There are other graphs and links to dedicated data pages for Washington State, Oregon, Seattle, Portland, Vancouver, and Canada. On these pages there are more graphs and links to the data that created the graphs.
The 2021 Atlantic hurricane season starts today, June 1. Our colleagues at NOAA are predicting another active season, with an above average number of named storms. At NASA, we’re developing new technology and missions to study storm formation and impacts, including ways to understand Earth as a system.
The third fact:
Climate change is likely causing storms to behave differently. One change is in how storms intensify: More storms are increasing in strength quickly, a process called rapid intensification, where hurricane wind speeds increase by 35 mph (or more) in just 24 hours.
In 2020, a record-tying nine storms rapidly intensified. These quick changes in storm strength can leave communities in their path without time to properly prepare.
After about a 4 year hiatus, the EPA’s page Climate Change Indicators in the United Stats has been updated with “Twelve new indicators and several years of data have been added to EPA’s indicator suite.” One new indicator is Permafrost:
The Deadhorse site in northern Alaska had the highest rate of temperature change, at +1.5°F per decade. The Livengood site in interior Alaska was the only site to get cooler over the period of record, though only slightly. Overall, permafrost temperatures have increased at an average rate of 0.6°F per decade.
There are csv files to download the data and background information about the indicators. This is an excellent resource page.
