Tag Archives: climate change

From the NOAA Global Climate Report – May 2020:

The global land and ocean surface temperature for May 2020 tied with 2016 as the highest in the 141-year record at 0.95°C (1.71°F) above the 20th century average of 14.8°C (58.6°F). The 10 warmest Mays have all occurred since 1998; however, the 2014–2020 Mays are the seven warmest in the 141-year record. May 2020 also marked the 44th consecutive May and the 425th consecutive month with temperatures, at least nominally, above the 20th century average.

The global land-only surface temperature for May 2020 was also the highest on record at 1.39°C (2.50°F) above the 20th century average of 11.1°C (52.0°F). This was 0.04°C (0.07°F) above the previous record set in 2012. The 10 highest May global land-only surface temperature departures have occurred since 2010.

The May 2020 global ocean-only surface temperature was near-record warm at 0.79°C (1.42°F) above average. This value was only 0.01°C (0.02°F) shy of tying the record warm May of 2016.

May time series data here. Climate.gov provides a summary of May 2020 in their post Was May 2020 warm and dry or cool and wet across the U.S.? It depends… by Rebecca Lindsey (6/9/2020)

From the climate.gov article Brief periods of dangerous humid heat arrive decades early  by Alison Stevens (5/12/2020):

The paper authors used an index called “wet-bulb temperature” based on weather station temperature and humidity data. The reading, from a thermometer when covered in a wet cloth, is related to how muggy conditions feel. This map shows locations that experienced extreme heat and humidity levels briefly (hottest 0.1 percent of daily maximum wet-bulb temperatures) from 1979–2017. Darker colors show more severe combinations of heat and humidity. Some areas have already experienced conditions at or near humans’ survivability limit of 35°C (95°F).

Who’s close to the 95°F?

The authors identified over 7,000 past occurrences of wet-bulb temperatures above 88°F (31°C), over 250 above 91°F (33°C) around the world, and two stations that reported multiple daily-maximum wet-bulb temperatures above 95°F. These extremes occurred for 1–2 hours in parts of coastal southwest North America, South Asia, and the coastal Middle East.

The southeastern United States, especially along the Gulf of Mexico, had multiple incidences of wet-bulb temperatures at or above 88°F; specifically, in east Texas, Louisiana, Mississippi, Alabama, the Florida Panhandle, Arkansas, and North Carolina. Parts of India, Pakistan, northwestern Australia, the coast of the Red Sea, and areas along the Gulf of California in Mexico saw even higher extremes.

The article links to the original paper.

The Climate.gov article 2010-2019: A landmark decade of U.S. billion-dollar weather and climate disasters by Adam B. Smith (1/8/2020) reports:

During 2019, the U.S. experienced a very active year of weather and climate disasters. In total, the U.S. was impacted by 14 separate billion-dollar disasters including: 3 major inland floods, 8 severe storms, 2 tropical cyclones (Dorian and Imelda), and 1 wildfire event. 2019 also marks the fifth consecutive year (2015-19) in which 10 or more separate billion-dollar disaster events have impacted the U.S.

Historical context:

In broader context, the total cost of U.S. billion-dollar disasters over the last 5 years (2015-2019) exceeds $525 billion, with a 5-year annual cost average of $106.3 billion (CPI-adjusted), both of which are records. The U.S. billion-dollar disaster damage costs over the last decade (2010-2019) were also historically large, exceeding $800 billion from 119 separate billion-dollar events. Moreover, the losses over the most recent 15 years (2005-2019) are $1.16 trillion in damage from 156 separate billion-dollar disaster events.

The article has other graphs and tables.  These events are tracked on NOAA’s Billion-dollar Weather and Climate Disasters: Overview page.

For those of us living in the northeast or a good part of the U.S. we might have felt that April was cold and it was. It is easy to use that as evidence that climate change is “fake news” yet it is good to keep in mind that if it is cold where you are it is likely much warmer somewhere else. The map here is from NASA’s GISS Surface Temperature Analysis page where similar maps can be made for a variety of time periods.  Here we can see that for April 2020 parts of the U.S. and Canada where one of the  few cold spots in the world. The rest of the planet was warmer.

NOAA’s Global Climate Report – April 2020 notes:

Averaged as a whole, the global land and ocean surface temperature for April 2020 was 1.06°C (1.91°F) above the 20th century average of 13.7°C (56.7°F) and the second highest April temperature in the 141-year record. Only April 2016 was warmer at +1.13°C (+2.03°F). The eight warmest Aprils have occurred since 2010. April 2016 and 2020 were the only Aprils that had a global land and ocean surface temperature departure above 1.0°C (1.8°F).

Time series data is available on the NOAA page. Note that NASA uses 1951-1980 as their baseline while NOAA is using the 20th century. This accounts for the slight differences in their calculations on April’s anomaly from the baseline.

From the NOAA Global Climate Report – March 2020:

Averaged as a whole, the global land and ocean surface temperature for March 2020 was 1.16°C (2.09°F) above the 20th century average of 12.7°C (54.9°F) and the second highest in the 141-year record. Only March 2016 was warmer at 1.31°C (2.36°F). The 10 warmest Marches have all occurred since 1990, with Marches of 2016, 2017, 2019, and 2020 having a global land and ocean surface temperature departure from average above 1.0°C (1.8°F). The March 2020 global land and ocean surface temperature departure tied with February 2020 and December 2015 as the third highest monthly temperature departure from average in the 1,683-month record. Only February and March 2016, when a strong El Niño was present in the tropical Pacific Ocean, had higher temperature departures.

Data for the graph here.

From the article The 2019/2020 summer of Antarctic heatwave by Sharon A. Robinson et. e. (3/30/2020) in Global Change Biology:

Heatwaves are rarely reported in Antarctica, but elsewhere are often classified as three consecutive days with both extreme maximum and minimum temperatures. Using this classification, Casey experienced a heatwave between 23 and 26 January with minimum temperatures above zero and maximum temperatures above 7.5°C. Casey also recorded its highest maximum temperature ever (9.2°C) on 24 January followed by its highest minimum (2.5°C) the following morning.

Interestingly,

In the past, much of East Antarctica has been spared from rapid climate warming due in part to ozone depletion, which cools surface temperatures slightly and enhances the strength of the westerly wind jets which shield Antarctica from more northerly warming air (Bornman et al., 2019; Robinson & Erickson, 2015).

But,

 In late 2019, stratospheric warming led to an early breakup of the ozone hole (Lewis, 2019) and Antarctic temperature records started to break (Figure 1a). In what we believe is a first, we report a heatwave event at Casey Station, East Antarctica (Figure 1b) in January, to add to the record high temperatures reported for Antarctica in February.

Impacts,

Although it is too early for full reports, this warm summer will have impacted Antarctic biology in numerous ways, probably leading to long‐term disruptions at ecosystem, community and population scales.

From NOAA’s Global Climate Report  – February 2020:

Averaged as a whole, February 2020 was near-record warm with a global land and ocean surface temperature departure from average of 1.17°C (2.11°F) above the 20th century average. Only February 2016 was warmer.

The February 2020 temperature departure from average was also the third highest monthly temperature departure from average for any month in the 1,682-month record. Only March 2016 (+1.31°C / +2.36°F) and February 2016 (+1.26°C / +2.27°F) had a higher temperature departure.

This means that the February 2020 global land and ocean surface temperature departure from average was the highest monthly temperature departure without an El Niño present in the tropical Pacific Ocean, surpassing the previous record set only last month (January 2020).

The data is available for the graph copied here. Click on Temperature Anomalies Time Series for February.

Climate Central has put together their 2020 Spring Package (2/2/2020) with information and a selection of city graphs. For example

Analyzing average spring temperatures since 1970, the top increases occurred in the Southwest—where spring is the fastest warming season. Reno, Nev. topped the list with an increase of 7.2°F, followed by Las Vegas, Nev. (6.4°F), El Paso, Texas (5.8°F), and Tucson (5.8°F). In general, 81% (197) of the 242 cities analyzed warmed by at least 1°F over the past fifty years. 

There are four different graph selections for spring: Average Temperature, Days Above Normal, Last Freeze, and a National Map. For the first three you can select from various cities. For example, I chose the graph for last freeze for Duluth, MN, which shows that on average the last freeze is occurring almost two weeks sooner.

The graphs are set up for easy download but there isn’t corresponding data. A previous post How much have fall nighttime temperatures risen? provides details on how to obtain this type of data.

No, as can be easily seen by the graphic here copied from the NASA article There is No Impending ‘Mini Ice Age’ (2/13/2020). At the same time we won’t be seeing an ice age anytime soon:

This is called a “Grand Solar Minimum,” and the last time this happened, it coincided with a period called the “Little Ice Age” (a period of extremely low solar activity from approximately AD 1650 to 1715 in the Northern Hemisphere, when a combination of cooling from volcanic aerosols and low solar activity produced lower surface temperatures).

Even if a Grand Solar Minimum were to last a century, global temperatures would continue to warm. Because more factors than just variations in the Sun’s output change global temperatures on Earth, the most dominant of those today being the warming coming from human-induced greenhouse gas emissions.

The article has another time series of solar irradiance with a source.

From the NOAA Global Climate Report – Annual 2019:

The year 2019 was the second warmest year in the 140-year record, with a global land and ocean surface temperature departure from average of +0.95°C (+1.71°F). This value is only 0.04°C (0.07°F) less than the record high value of +0.99°C (+1.78°F) set in 2016 and 0.02°C (0.04°F) higher than the now third highest value set in 2015 (+0.93°C / +1.67°F). The five warmest years in the 1880–2019 record have all occurred since 2015, …

The report contains summaries by region and has abundance of quantitative information such as:

North America was the only continent that did not have an annual temperature that ranked among its three highest on record. Overall, North America’s temperature was 0.90°C (1.62°F) above the 1910–2000 average, marking the 14th warmest year in the 110-year continental record. The yearly temperature for North America has increased at an average rate of 0.13°C (0.23°F) per decade since 1910; however, the average rate of increase is more than twice as great (+0.29°C / +0.52°F per decade) since 1981.

The graphic here is from NASA, NOAA Analyses Reveal 2019 Second Warmest Year on Record (1/15/2020). Time series data can be obtained from Climate at a Glance Global Time Series.