Fourth National Climate Assessment: A Dire Forecast for US if Action is Not Taken

The Fourth National Climate Assessment (NCA4) report was released rather inauspiciously last week on the day after Thanksgiving – a traditionally slow news day. Nevertheless, the report is out and it clearly states, “the evidence of human-caused climate change is overwhelming and continues to strengthen.”

The massive report, considered volume two of NCA4, builds on the Climate Science Special Report issued last year. It gives a detailed account of what the impacts will be across the country and how the worst effects could be avoided.

The U.S average temperature, according to the report, has increased by 1.8°F since 1901, and is projected to continue rising. Over the next few decades, temperatures are projected to rise another 2.5°F.  By the end of the century, our average temperature could soar by as much as 11.9°F if greenhouse gas emissions continue to increase unchecked.

The report also looks at the long-term economic impacts for the country as the average temperature continues to climb. Costs from rising sea levels could reach as high as $118 billion and the projected total for damaged infrastructure is $32 billion. This is in addition to the reduced agricultural productivity expected from high heat and extended drought events. Overall, the report warns that if significant steps are not taken, climate change could slash the US economy’s GDP by 10% by the end of the century.

Not all doom and gloom, the report’s authors emphasize, “These impacts are projected to intensify—but how much they intensify will depend on actions taken to reduce global greenhouse gas emissions and to adapt to the risks from climate change now and in the coming decades.”

While similar in theme to the IPCC report from the UN, this assessment focuses solely on the United States. Emphasizing the fact that rising temperatures will affect different parts of our vast country in different ways, the NCA breaks the nation down into specific regions. It details the current and future impacts of climate change in each one:

The report also includes a supplemental set of State Climate Summaries that give a clear idea of what to expect in each of the 50 states as well as the US territories.

Mandated by Congress under the Global Change Research Act, this exhaustive 1600 page peer-reviewed report was produced by 300 scientists from 13 different government agencies. Published every four years, it is considered this country’s most authoritative statement on climate change.

Annual average temperatures across the United States are projected to increase over this century, with greater changes at higher latitudes as compared to lower latitudes, and greater changes under a higher scenario (RCP8.5; right) than under a lower one (RCP4.5; left). This figure shows projected differences in annual average temperatures for mid-century (2036–2065; top) and end of century (2071–2100; bottom) relative to the near present (1986–2015). Image credit: Fourth NCA, Vol II, figure 2.4.

October 2018: Earth’s Second Warmest October on Record

Our global temperature continued its upward trend last month with October 2018 marking the second warmest October ever recorded on this planet. Only October 2015 was warmer.

According to the State of the Climate report by NOAA’s National Centers for Environmental Information, Earth’s combined average temperature for the month – over both land and sea surfaces – was 58.65°F, which is 1.55°F above the 20th-century average. October also marked the 406th consecutive month with a global temperature above its long-term norm. That means the last time any month posted a below average reading was December 1984.

While heat dominated most of the planet this October, some places were particularly warm. These included eastern Russia, northern Australia, Alaska, and most of the east coast of the United States. These soaring temperatures are largely attributed to the long-term trend of human-caused climate change. ENSO-neutral conditions prevailed in October, which means there was neither a warm El Niño nor a cool La Niña in the Pacific to influence global weather patterns.

For many people in the central US, however, October was relatively cold. These chilly temperatures, driven by a deep dip in the jet stream, helped cool the national average to 0.3°F below normal for the month. To put this disparity into context, consider that the contiguous United States constitutes less than 2% of the total surface of the Earth. This detail highlights the fact that climate change is a complex global phenomenon that involves much more than the short-term weather that is happening in our own backyards.

Year to date, the first ten months of 2018 were the fourth warmest such period of any year on record. Global temperature records date back to 1880.

October 2018 was the second warmest October ever recorded on this planet. Credit: NOAA

Film Looks at Climate Change as a National Security Issue

Today is Veterans Day, a day to honor the men and women who have served in the armed forces. As such, it seems an appropriate time to highlight “The Age of Consequences” – a film that looks at climate change through the lens of national security and global stability.

Directed by Jared Scott, the film features a number of interviews with members of the military. While quick to point out that climate change is not the sole cause of any particular conflict, they discuss how it acts as a “threat multiplier” or “accelerant of instability”.

More specifically, the film shows how water and food shortages, drought, extreme weather, and sea-level rise have stressed social tensions to the point of armed conflict and/or mass migration in some of the more volatile regions of the world. Released in 2016, the war in Syria, the rise of ISIS, and the European refugee crisis are prominently featured.

Watch the trailer here:

Fall Foliage and Climate Change

Autumn is a season well known for its colorful foliage. Driven by the combination of sunlight, temperature, and precipitation, local displays vary from year to year. However, as the climate changes, so too will this familiar natural phenomenon.

As daylight hours decrease in the fall, there is less sunlight available to power photosynthesis – the chemical process that provides nutrients to trees by converting carbon dioxide and water into glucose, which is consumed by the tree and oxygen, which is released. This, in combination with falling temperatures, tells a tree to start preparing for winter.

To do this, a tree turns off its food producers by slowly corking the connection between leaf-stems and its branches.  This blocks the movement of sugars from the leaves to the tree as well as the flow of water from the roots to the leaves.  As a result, the leaves stop producing chlorophyll, the agent of photosynthesis and the reason for the green color of summer foliage.  As the green fades, other chemicals that have been present in the leaves all along begin to show.  These include xanthophyll and carotene, which produce yellow and orange leaves, respectively. Red to purplish colors are the result of anthocyanin, a chemical produced as a result any remaining sugars trapped in a leaf.

The change of leaf color happens every year, but the timing and duration of the displays are largely dependent on temperature and rainfall. Dry, sunny days and cool nights are the ideal recipe for beautiful fall foliage. Warmer and wetter conditions, on the other hand tend to delay the color change. However, extreme conditions, such as high heat, frost, excessive rain, or drought, can be a source of stress for trees and cause the colors to change early and the leaves to fall off faster.

As our climate changes, so too will displays of fall foliage. With warmer and wetter conditions forecast for the northeast, autumn colors are expected to peak later and disappear sooner. While there will still be variability from year to year, the fall foliage season in general is expected to get shorter. Furthermore, with the increasing probability of extreme weather events, such as storms with heavy rain, leaves could be swept from trees, effectively ending the season in a single day.

These changes will have more than an aesthetic affect. They are sure to have an impact on the multi-billion-dollar a year leaf-peeping ecotourism industry in several states.

Credit: Climate Central

September 2018: Earth’s Fourth Warmest September on Record

Our global temperature continued its upward trend last month with September 2018 tying 2017 as the fourth warmest September ever recorded on this planet.

According to the State of the Climate report by NOAA’s National Centers for Environmental Information, Earth’s combined average temperature for the month – over both land and sea surfaces – was 60.4°F, which is 1.40°F above the 20th-century average. September also marked the 405th consecutive month with a global temperature above its long-term norm. That means the last time any month posted a below average reading was December 1984.

While heat dominated most of the planet this September, some places were particularly warm, including much of Europe, Russia, the Middle East, and both the eastern and southwestern regions of the United States. For the contiguous US as a whole, September 2018 marked the fourth warmest September on record.

These soaring temperatures are largely attributed to the long-term trend of human-caused climate change. ENSO-neutral conditions prevailed in September, which means there was neither a warm El Niño nor a cool La Niña in the Pacific to influence global weather patterns.

Year to date, the first nine months of 2018 were the fourth warmest such period of any year on record. Global temperature records date back to 1880.

September 2018 was the planet’s 4th warmest September on record. Credit: NOAA

Special IPCC Report: Massive Global Effort Needed to Avoid Worst Climate Change Impacts

The UN’s Intergovernmental Panel on Climate Change (IPCC) released its Special Report on Global Warming of 1.5°C on Monday. It clearly states that the impacts of climate change will be greater at a lower degree of warming than previously thought.

Written by 91 scientists from 40 countries, the report finds that quick and dramatic action needs to be taken to avoid a warming increase of 1.5°C (2.7°F) above pre-industrial levels. Without aggressive cuts to global greenhouse gas emissions, the planet is expected to  reach this warming threshold between 2030 and 2052.

The Paris Agreement set the target of holding global warming to 2°C (3.6°F) above pre-industrial levels and urged countries to pursue an even tighter cap of 1.5°C (2.7°F) if possible. This more aggressive goal was added at the urging of officials from low-lying island nations – those most susceptible to sea level rise. As such, the IPCC began to look more closely at what 1.5°C (2.7°F) of warming would mean for people and ecosystems around the planet.

Previously, scientists thought that the most severe effects of climate change could be held off if the planet stayed below 2°C (3.6°F) of warming. However, this report shows that those impacts will come sooner, at the 1.5°C (2.7°F) mark. These consequences include coastal inundation from rising seas, worsening droughts and wildfires, as well as food shortages and mass die-offs of coral reefs. An extra half-degree Celsius, from 1.5°C to 2°C, would magnify those impacts.

To avoid the worst case of these types of effects, the report says the global economy needs to be transformed within the next few years. More specifically, greenhouse gas pollution must be reduced by 45% from 2010 levels by 2030, and 100% by 2050. While this is technically possible, the report also highlights it will require enormous political will.

Under the Paris Agreement, every country around the globe submitted individualized plans to reduce its greenhouse gas emissions known as nationally determined contributions (NDCs). While an important first step, these are not enough to meet the agreement’s 2°C (3.6°F) goal, to say nothing of the more aspirational target of 1.5°C (2.7°F).  In fact, they would allow for 3°C (5.4°F) of warming by the end of the century. However, the agreement does legally obligate countries to reconvene every five years to present updated plans spelling out how they will deepen their emissions cuts.

For the US, the second largest carbon polluter in the world after China, political will for climate action is something that is sorely lacking. President Trump announced plans to withdraw the US from the Paris Climate Agreement and has been rolling back his predecessor’s Clean Power Plan, the principle aspect of this country’s NDC.

Nonetheless, 2018 marks the halfway point between the passage of the Paris Climate Agreement in 2015 and the 2020 target for countries to begin ratcheting up their greenhouse gas cutting commitments. As such, this new report will be key to the discussions at the upcoming UN Climate Conference in Katowice, Poland this December.

Credit: Climate Matters

This Year’s “Climate Week NYC” Will Focus on Accelerating Climate Action

Climate Week NYC begins on Monday. This annual global summit takes place alongside the UN General Assembly and brings together leaders from a variety of sectors, including government, business, and non-profit organizations, to discuss solutions to climate change.

Organized by The Climate Group since 2009, the goal of the conference is to keep this pressing issue high on the global agenda. This year, which marks the halfway point between the passage of the Paris Climate Agreement in 2015 and the 2020 target for countries to ratchet up their greenhouse gas cutting commitments, the event will focus on ways to accelerate climate action. The ultimate goal of the non-binding Paris Accord is to limit global warming to 2°C (3.6°F) above pre-industrial levels

Public events to raise awareness and support of the summit’s mission are scheduled all week around the city, from September 24-30. They range in style from panel discussions and seminars to concerts and exhibitions. For the full program of events, go to the Climate Week website.

August 2018: Earth’s Fifth Warmest August on Record

Our global temperature continued its upward trend last month. August 2018 marked not only the fifth warmest August on record, but also closed out the planet’s fifth warmest June to August season – a period known as meteorological summer in the northern hemisphere.

According to the State of the Climate report by NOAA’s National Centers for Environmental Information, Earth’s combined average temperature for August – over both land and sea surfaces – was 61.43°F, which is 1.33°F above the 20th-century average. This August also marked the 404th consecutive month with a global temperature above its long-term norm. That means the last time any month posted a below average reading was December 1984.

Globally, the collective period of June, July, and August was also unusually warm. NOAA reports that Earth’s average temperature for the season was 1.33°F above the 20th century average of 60.1°F. That makes it the fifth warmest such period on record.

While heat dominated most of the planet during this three-month stretch, some places were particularly warm, including much of Europe, central Asia, and the southwestern United States. For the contiguous US as a whole, the season tied with 1934 as the fourth warmest summer on record.

These soaring temperatures are largely attributed to the long-term trend of human-caused climate change. ENSO-neutral conditions prevailed in August, which means there was neither a warm El Niño nor a cool La Niña in the Pacific to influence global weather patterns.

Year to date, the first eight months of 2018 were the fourth warmest such period of any year on record. Global temperature records date back to 1880.

Credit: NOAA

July 2018: Earth’s Fourth Warmest July on Record

Our global temperature continued its upward trend last month with July 2018 marking the fourth warmest July ever recorded on this planet. Only July 2015, 2016, and 2017 were warmer, with July 2016 holding the top spot.

According to the State of the Climate report by NOAA’s National Centers for Environmental Information, Earth’s combined average temperature for July – over both land and sea surfaces – was 61.75°F, which is 1.35°F above the 20th-century average. July also marked the 403rd consecutive month with a global temperature above its long-term norm. That means the last time any month posted a below average reading was December 1984.

While heat dominated most of the planet this July, some places were particularly warm, including much of Europe, Scandinavia, the western United States, and parts of southern Asia. For the contiguous US as a whole, July 2018 tied with 1998 as the eleventh warmest July on record.

These soaring temperatures are largely attributed to the long-term trend of human-caused climate change. ENSO-neutral conditions prevailed in July, which means there was neither a warm El Niño nor a cool La Niña in the Pacific to influence global weather patterns.

Year to date, the first seven months of 2018 were the fourth warmest such period of any year on record. Global temperature records date back to 1880.

July 2018 was the planet’s 4th warmest July on record. Credit: NOAA

June 2018: Earth’s Fifth Warmest June on Record

Our global temperature continued its upward trend last month with June 2018 marking the fifth warmest June ever recorded on this planet. The ten warmest Junes have all occurred since 2005, with 2016 earning the top spot.

According to the State of the Climate report by NOAA’s National Centers for Environmental Information, Earth’s combined average temperature for June – over both land and sea surfaces – was 61.25°F, which is 1.35°F above the 20th-century average. June also marked the 402nd consecutive month with a global temperature above its long-term norm. That means the last time any month posted a below average reading was December 1984.

While heat dominated most of the planet this June, some places were particularly warm, including much of Europe, central Asia, and parts of the Middle East. Here in the contiguous US, it was our third warmest June on record.

These soaring temperatures are largely attributed to the long-term trend of human-caused climate change. ENSO-neutral conditions prevailed in June, which means there was neither an El Niño nor a La Niña in the Pacific to influence global weather patterns.

Year to date, the first six months of 2018 were the fourth warmest such period of any year on record. Global temperature records date back to 1880.

June 2018 was the planet’s 5th warmest June on record. Credit: NOAA