Weather was one of the biggest factors in the American Civil War. It affected every part of the conflict. The American Civil War took place at the very tail end of what is called the Little Ice Age. Annual fluctuations in weather were both terrible and constant and winters were much colder than today. One year could bring an intensely cold winter and biting easterly winds, while the next year might deliver heavy rains and raging heat. Official weather recording devices were established in the 1850s by the Smithsonian Institution and many Civil War era men and women recorded daily weather-related information in diaries and letters so that it is possible to get a general idea of the weather in a variety of places during the years of the war. Weather shaped battles and campaigns. In the Seven Days constant rain, swollen rivers forced changed tactics and the rain and cold demoralized men and resulted in a stew of malaria, typhoid, dysentery for the Union forces retreating to Harrison’s landing. In another example, during the engagements at Mill Springs and Chantilly, the actual fighting capability of the soldiers was impeded by heavy rains, which made the ammunition for their small arms and artillery useless and prevented men from participating in the fighting or requiring them to attempt hand-to-hand combat. Additionally, an unusual atmospheric phenomenon called an acoustic shadow is recorded as having masked the sounds of battle. This prevented both sides from using sound to identify areas of combat, preventing some units from combining against enemy forces and causing others to be nearly overwhelmed because there was no way to tell that an enemy unit was in close proximity. Heat was as devastating to Civil War soldiers as rain and cold particularly for armies operating in the deserts of California, Arizona, New Mexico and Texas. Weather also affected the operations of navies, an example being the loss of the USS Monitor in 1862 during a storm. Soldiers on both sides wrote about the weather constantly and complained just about as often, but however much soldiers suffered, it was worse for prisoners of war. At Andersonville and other prison camps, the miserable little shanties and other thrown-together shelters were no help at all for exposed, starving men. Many died of diseases related to exposure, and others simply froze to death. One of the most notable effects of weather on armies was Burnside’s Mud March of January 20-21, 1863. The Federal forces marched out into a countryside swept by a heavy storm that turned roads into swamps and turned back once the going became impossible. The Civil War was greatly affected by the weather, whether the armies were those of the Trans-Mississippi, the Far West, the Deep South, or Virginia. Illness in the ranks, a result of both seasons and weather, decimated all armies and impacted every aspect of soldier life, from the planning of grand battles to the digging of latrines.
"Snowy Morning on Picket" Not attributed
From the January 30, 1864 issue of Harper's Weekly Page 68.
Weather in the Mid-Nineteenth Century: The Little Ice Age
"Conversation about the weather is the last refuge of the unimaginative," said Oscar Wilde. Of course, Oscar Wilde was not a Civil War general, for many of whom weather was in fact very important.
Weather was one of the biggest factors in the American Civil War. It affected every part of the conflict. “The difference between weather and climate is the measure of time: weather is what the atmospheric conditions are over a short period of time and climate is how atmospheric conditions behave over relatively long periods of time.” The American Civil War took place at the end of what is called the Little Ice Age. This climate change lasted from the 1300s to the mid 1800s and was responsible for Europe and North America having to endure much colder winters than those of the 21st century. Annual fluctuations in weather were both terrible and constant.
Historical climatology is a small but passionate field that emerged after the IGY. Scientists and humanities scholars realized the climates they had assumed they knew would have, instead, varied significantly throughout history. Historical climatologists seek to reconstruct past climates in order to consider the role they played in human history.
Despite the name "Ice Age" this time period actually encompassed many dramatic changes in weather. By the time the Civil War began, the Little Ice Age was ending. Although records indicate a warming trend of 2-4ºF, this did not mean it was anywhere near actually warm. Virginia experienced alternating extreme precipitation, scorching heat, and bitter cold.
Keeping Weather Records
Prior to the mid-1800s there was no regulated way to track weather. In 1849 the Smithsonian Institution, by volunteering to donate weather-recording devices, established an observation network. By 1860, over 500 stations were telegraphing weather reports to newspapers such as the Washington Evening Star. Unfortunately, this work was interrupted by the Civil War. Detailed information from a variety of locations is difficult to piece together, but it is possible to get a general idea of the weather in a variety of places during the years of the war. With accurate weather instruments available commercially, many Civil War era men and women recorded daily weather-related information in diaries and letters. Robert Krick’s bookCivil War Weather in Virginiais a compilation of the work of the Reverend C. B. Mackee’s meticulous recordings of temperature, taken in Georgetown, at 7:00 a.m., 2:00 p.m., and 9:00 p.m., almost every day of the war. These are supplemented with other observations from newspapers and personal and military correspondence. Robert Krick is rumored to find it humorous that, after a lifetime of Civil War studies, his “best seller” is a book about weather.No one appreciated knowing about the weather more than a Civil War general, and on February 9, 1870 former general and then-President Ulysses S. Grant signed into law the first national weather service, utilizing the technology of the U.S. Army's Signal Service.
Weather Shaped Battles and Campaigns
Weather, one of the biggest factors of the American Civil War, is often overlooked. Both strategy and tactics were affected, as generals, privates, and presidents gazed at the skies, trying to decide when to begin campaigns (or end them), guessing at river floodings and the accumulation of mud. It was not only General Burnside who had difficulties with Confederate mud. During the Battle of New Market, May 15, 1864, the rains were so unrelenting that Confederate troops, crossing a wheat field, lost so many pieces of footwear that the field became known as the “field of lost shoes.”
One early example of the effect of weather is Major General George McClellan's Seven Days Battles (part of the Peninsula Campaign) in Hanover and Henrico counties, Virginia. The series of six battles took place from June 25-July 1, 1862. The Seven Days is usually remembered as a defeat for the Union and the campaign in which Confederate General Joseph E. Johnston was wounded and Robert E. Lee was chosen to replace him. McClellan complained to President Lincoln (and anyone who would listen to him) about the constant rain and the resulting rise in the swollen rivers and deep bogs which made up much of the landscape of the Virginia Peninsula. Even after McClellan sent his men forward, such weather continued to impede the Union advance toward Richmond.
On both sides, soldiers were negatively impacted during this time. "Rain was the greatest discomfort a soldier could have; it was more uncomfortable than the severest cold with clear weather," wrote Confederate private Carleton McCarthy. A Pennsylvania cavalryman agreed, writing, "There is nothing in our mode of life to injure our health, but exposure to all kinds of weather. Sometimes we have to stay out all night, and the ground is now so muddy that we cannot walk fast without getting our feet wet and consequently cold." By the time McClellan decided to end the campaign, the health of the Union forces had become almost completely untenable. The retreating army at Harrison's Landing was a stew of malaria, typhoid, dysentery, and everything else imaginable that could afflict a wet, tired, malnourished, wounded group of men suffering torrential rains and high heat.
Hostile weather played a great part in the shaping of military engagements and campaigns, which often involved planning around "torrential rain, flooding, and mud that determined commanders' decisions in decisive ways." Rain, fog, mud and snow often transformed the battlefield into a much more challenging landscape in which to attempt to direct an army. Adverse conditions often forced the delay, cancellation, or complete alteration of the military plans on both sides of the war. There was simply no accurate way to predict upcoming weather conditions or the duration of current weather. For example, during the engagements at Mill Springs and Chantilly, the actual fighting capability of the soldiers was impeded by heavy rains, which made the ammunition for their small arms and artillery useless and prevented men from participating in the fighting or requiring them to attempt hand-to-hand combat. Additionally, an unusual atmospheric phenomenon called an acoustic shadow is recorded as having masked the sounds of battle. An acoustic shadow is of little concern today, but when a battle depended on sound to identify where troops were or were not, it was of great importance. The phenomenon known as an acoustic shadow concerns the area where sound does not penetrate. This may be due to the absorption or refraction of sound waves. This phenomenon prevented both sides from using sound to identify areas of combat, preventing some units from combining against enemy forces and causing others to be nearly overwhelmed because there was no way to tell that an enemy unit was in close proximity. Another example is the fight at Iuka (September 1862) when two Union columns commanded by Major Generals Edward Ord and William Rosecrans failed to concentrate against Major General Sterling Price's Confederate Army of the West. Following the battle, Ord explained that for him and his men: “the wind, freshly blowing from us in the direction of Iuka during the whole . . . [of the battle] prevented our hearing the guns and co-operating with Rosecrans.”
Heat was as devastating to Civil War soldiers as rain and cold. The heat in the West—–the deserts of what are now California, Arizona, New Mexico and Texas—had long been an enemy of human survival. Southwestern deserts alternated between long periods of blistering heat and a few weeks of monsoonal rains that were responsible for flash-flooding devastation. The Federal army had built forts along rivers in order to permit travel to the West, and caches of food and water were routinely planted along trails at strategic points. When Texas seceded and took much of the Federal army with it, now-Confederate soldiers sought to disrupt this method of travel. Historian Megan Kate Nelson detailed this struggle in The Blue, the Gray, and the Green, one of the few books to propose an environmental approach to the history of the Civil War. Whether one fought under Lieutenant Colonel Edward Canby, Major Isaac Lynde, Confederate Lieutenant Colonel John Baylor, or Confederate General Henry H. Sibley, the truth of the fighting could be found in the long lines of graves and skeletonized remains that marked the paths of every army fighting in heat over 110 degrees, with no shade, no scientific concept of hydration, and no water to do anything about it even if they had understood it.
Weather did not only affect the armies. Naval vessels, always at the whims of Mother Nature, were especially vulnerable. Even such seemingly invulnerable vessels like the ironclads suffered. The USS Monitor was lost off the coast of Cape Hatteras in North Carolina on December 31, 1862. A survivor wrote of the incident:
The weather was heavy with dark, stormy-looking clouds and a westerly wind. We passed out of the Roads and rounded Cape Henry …when the wind shifted to the south-south-west and increased to a gale. The sea rolled over us as if our vessel were a rock in the ocean only a few inches above the water.
In 1861 all storms classed as hurricanes were only categorized as Category 1 and none made landfall although the one in the first days of November disrupted the federal fleet off Port Royal, South Carolina. In 1862 there were no major tropical storms and there were only two in 1863, both considered Category 2. 1864 presented no storm activity that affected the United States at all, and the few storms of 1865 only made landfall after the formal surrenders of all Confederate forces. In fact, there were no damaging storms that hit the U. S. until 1871. Although earthquakes are not weather, their absence or presence works in much the same way. A check of the earthquake data through the U. S. Geographical Survey (USGS) website shows no earthquakes with a magnitude of 7 or greater occurred during the Civil War. Luckily there were very few earthquakes at all recorded west of California.
The Fog of War
Colonel Lonsdale Hale first used the phrase "fog of war" in 1896, but he was referring to the state of ignorance and confusion resulting from battlefield turmoil. The literal "fog" of war during the Civil War existed as well. The existence of microclimates in places like Virginia and Maryland has not been studied extensively, but these small climate anomalies were responsible for isolated rain showers, and fog. The Antietam Valley is one example. Fog in river valleys is a common event, but it becomes more common during the late summer and early fall. Such a fog covered the Antietam Valley during the morning hours of September 16, 1862. It is reported that visibility was only fifteen or twenty feet in any given direction. General McClellan wired Henry Halleck that he was unsure of the placement of Robert E. Lee's southern troops, but would attack as soon as he was positive of their disposition. The fog finally burned off, but not completely. There were still pockets of thick vapor obscuring the broken and wooded ground behind the hills, which hid Rebel troops. What to McClellan looked like a narrow summit sparsely surrounded by woods was in reality a broad piedmont of forest and ravine that provided cover for Confederate troops and artillery, with little geographical opportunity for a Yankee attack. The initial impression was all an illusion, and McClellan's plans were useless when the reality of the situation exposed itself.
Impacts on the Soldier Experience
Rain and heat were not the only problems offered by the weather. Soldiers on both sides wrote about the weather constantly and complained just about asoften. Winters were bitter and boring, and there was little to do. On both sides, most soldiers slept on the ground, or in flimsy tents. Union soldiers are often depicted in winter quarters of log cabins with chimneys, but they were not known for being exactly warm and snug. As winter wore on, spirits drooped, health was affected, and home-centered holidays like Christmas and New Years were missed. Homesickness was reported to company surgeons as a cause of ill health.
Exposure was awful for the troops, but it was even worse for prisoners of war. At Andersonville and other prison camps, the miserable little shanties and other thrown-together shelters were no help at all for exposed, starving men. Many died of diseases related to exposure, and others simply froze to death. The diary of Union Sergeant William G. Thiselton, 6th New York Heavy Artillery, Company “J” describes one of the results of nighttime picket duty in the winter: "November 24, 1863…the weather very cold some of the pickets were frozen to death in the rifle pits at Mine Run."
Not everything was completely bleak, however. TheGreat Snowball Battle of Rappahannock Academy was one of winter’s high points in 1863. Three days of snow in mid-February left at least seventeen inches of snow on the ground of the Confederate Army camp near Fredericksburg, Virginia. General Robert F. Hoke, himself only twenty-six years old, took one look at all that snow and saw…victory! He formed his men into an attack force of snowballers, led by officers and using cavalry, skirmishers and infantry maneuvers to take the camp of Colonel William Stiles’ Georgia Brigade. The “severe pelting” began, with men from other units quickly joining in on both sides. At first, Hoke men invaded the Georgian camp, but were soon repelled by Stiles warlike organization of his men into columns of companies, each man ready to “fire” the snowball held in his hand. Stiles found out, however, that his “enemy” had fortified their camp, and haversacks were loaded to the brim with ammunition. With no need to reload, Hoke’s North Carolinians won the day, “whitewashing” the enemy with loose snow as a punishment before demanding a parole promise. Over 10,000 Confederates participated in this impromptu, but epic, snowball fight. One soldier wrote that it was, “one of the most memorable combats of the war.” The weather turned mild and rainy in the following days. Other snowball battles were documented during the Civil War, including a snowball fight atDalton,Georgia, but the Great Snowball Battle of Rappahannock Academy was unique in size, strategy and ample snow cover.
Other Notable Weather Incidents
One particularly (in)famous weather-related incident that should be mentioned here is the Mud March of January 20-21, 1863. Union general Ambrose Burnside, still stinging from his massive loss to the Confederates at Fredericksburg, decided to move his army against the South again by crossing the Rappahannock and executing a massive turning movement against Lee's troops, entrenched on the southern side of the river. On January 20, 1863, the day before General Burnside planned to begin his campaign, a winter wave cyclone hit the area. It brought copious amounts of precipitation. Historian James McPherson wrote:
As soon as the general got his army in motion on January 20 the heavens opened, rain fell in torrents, and the Virginia roads turned into swamps. Artillery carriages sank to their axels, men sank to their knees, and mules sank to their ears.
Burnside persisted, despite the treacherous Virginia clay. The churning up of the "sacred soil" by the boots of thousands of men, horses, and wheels turned the roads into deep, quicksand-like tracks and the end of the day of January 21 witnessed nearly 75,000 Yankees "bogged down and their equipment immobilized." Additionally, strong winds and temperatures in the lower 30s added to the soldiers' misery. The Army of the Potomac attempted to turn around in retreat the next day, much to the amusement of the nearby Confederates, who laughed and taunted the muddy troops with signs saying things like, "This Way to Richmond”. Would Burnside have attempted this fiasco had he known the weather in advance? There was no way for him to do so, but both his past loss at Fredericksburg and the inability to predict the weather certainly affected his military strategy.
In conclusion, the Civil War was greatly affected by the weather, whether the armies were those of the Trans-Mississippi, the Far West, the Deep South, or Virginia. The men fighting the war endured what amounts to a four-year camping trip complete with bugs, illness, and shooting. The constant outdoors exposure to all kinds of weather was of concern to every soldier. "There is much sickness in our Regiment, but we have beautiful weather now and I hope the general health will improve rapidly," wrote a hopeful infantryman from the 45th Georgia on June 16, 1862. Private Blackington, of Massachusetts, seconded this wish: "We have very pleasant weather out here now. It seems like summer. We have the merry birds singing their sweet melodious songs in the beautiful trees." Soldier morale could be raised by the weather as quickly as it could be cast down. Nevertheless, illness in the ranks, a result of both seasons and weather, decimated all armies and impacted every aspect of soldier life, from the planning of grand battles to the digging of latrines. Weather is a subject rarely mentioned in most accounts of the war. It is often considered an excuse for poor performance when it is mentioned at all. Going forward, perhaps historians would do better to consider the reality faced by Confederate and Federal armies. The danger, fatigue—both mental and physical, and the presence of life-threatening illnesses attacking the forces need to be factored into future accounts. War is far more than bullets or cannon fire. More than two-thirds of the casualties during the American Civil War came from illness and exposure—much of it a direct result of the weather.
1849: The Smithsonian Institution, by volunteering to donate weather-recording devices, established an observation network.
1850: Many scholars agree that this date marks the end of the meteorological period known as the Little Ice Age; a time of general warming followed.
July 21, 1861: The First Battle of Bull Run was fought in temperatures in the 90s with high humidity, causing serious issues with heatstroke among the soldiers.
January 29, 1862: The battle of Mill Springs was impeded by heavy, unrelenting rain.
April–June 1862: During the first half of the Peninsula Campaign, Union general George B. McClellan continually complained that he could not advance to Richmond because of rainy weather and flooded rivers, among other impediments.
June 25-July 1, 1862: McClellan finally moved the Army of the Potomac to the Virginia Peninsula in an attempt to take Richmond, the Confederate capital. Torrential spring rains caused the terrain to flood and the Virginia soil turned into a mass of sticky mud, culminating in the failure of McClellan's campaign.
September 1, 1862: Confederate General Thomas J. "Stonewall" Jackson clashed with Union General Isaac Stevens at the Battle of Chantilly during a heavy thunderstorm.
September 16, 1862: Fog influenced the outcome of the Battle of Antietam.
September 19, 1862: Battle of Iuka was mismanaged due to an atmospheric acoustic shadow.
December 31, 1862: The USS Monitor sank off the coast of Cape Hatteras, North Carolina, during a monstrous gale.
January 20–22, 1863: Union General Ambrose E. Burnside led troops on the Mud March, a failed winter offensive in Virginia, during torrential rains and heavy mud, lowering Union morale.
May 2, 1863: At the Battle of Chancellorsville, Confederate General Thomas J. "Stonewall" Jackson's men were shielded from view during their famous flanking maneuver, thanks to the absence of dust because of earlier rain showers.
November 24, 1863: Pickets froze to death in rifle pits at Mine Run.
March 22, 1864: The "Great Snowball Battle" took place between regiments of the Confederate Army of Tennessee in Dalton, Georgia.
May 5–6, 1864: During the Battle of the Wilderness, hot weather contributed to the spread of forest fires. On the subsequent march to Spotsylvania Court House on May 7, men experienced heat stroke and exhaustion as the temperature rose.
May 15, 1864: At the Battle of New Market, a terrific downpour occured. While crossing a wheat field, Confederate soldiers' feet get stuck in the mud, earning the field the title the "field of lost shoes."
February 1865: Union general William T. Sherman and his men successfully marched into South Carolina despite massive storms. Sherman proceeded to take Columbia and Charleston.
1870: Former general and then-President Ulysses S. Grant signed a law creating the first national weather service, utilizing the technology of the U.S. Army's Signal Service
1957-1958: The International Geophysical Year began to track carbon dioxide in the atmosphere, starting the field of historical climatology.
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