Natural Disasters: Present, Past and Future

I write and talk a lot about the effects Mother Nature has and has had on people and communities. You can read my list of published articles and books on this site here. My presentations are summarized here. I also try to maintain a bibliography of books and articles about the relationships of natural phenomena and family history. You can see the reading list here.

We are constantly bombarded (or so it seems lately) with news headlines and opinion pieces about natural disasters around the world, in many cases because of their purported connection with climate change. Differing opinions exist that events that we are observing now, around the world, are unique in terms of intensity, history and their impact on human settlements.

Many are related to short and long-term weather patterns: droughts, heat waves (the polar vortex in the winter), floods, storms, wildfires, etc. Other disasters that are part of the Earth’s normal geological processes include earthquakes, landslides, volcanic eruptions and tsunamis. All, of course, can cause distress and mayhem to people. As they have done for eons!

A short list of recent major events includes:

·         Drought in Western Canada, Western USA and around the world

·         Earthquakes in Japan, Russia, USA

·         Floods in New York and New Jersey (and Algeria, Australia, Bolivia, China, the Congo, Jordan, Nigeria, USA

·         Glacier collapse in Switzerland

·         Storms (including hurricanes and tornadoes) in Australia, Canada, Egypt, Kuwait, the Philippines, Tunisia, UK, USA

·         Wildfires in the Southeast Europe, Canada, Korea, USA

·         Volcanic eruptions in Iceland, Indonesia, Russia

News reports and some studies state that events are getting worse – in frequency, intensity and regional scope. But these comments only relate to a few past decades, not to the overall historical record.

The costs associated with damage from natural disasters have reached record levels. But they are mainly in areas where there are large populations and highly developed infrastructure. Would anyone doubt that the relative cost of the drought and fires in Europe in 1540 or 1842 would be much different on a per capita basis?

Our records of natural events, including written historical documents, only go back a few hundred years, in most regions much less time. For example, you can read about major storms in millions of newspaper articles going back to the early 18^th century.

Geological and geographical records show major catastrophic events have occurred regularly in past centuries and over hundreds of millions of years.

Regarding family history studies, it is informative to look at what is going on in the modern world to appreciate how such events may have affected our ancestors, who were not likely to have been as well prepared or warned about impending natural disasters.

To take one example of the present and relate to outcomes in the past, we can look at the drought conditions plaguing western North America. The current ongoing megadrought began in 2000. Such dry periods have not been rare occurrences in this region.

The medieval era in western North America was also characterized by widespread and regionally severe, sustained droughts. Proxy data, primarily in the form of tree rings, indicate decades-long periods of increased aridity illustrated as peaks on the graph and shown as red on the map from AD 1150 across the central and western U.S.

In the Colorado and Sacramento River basins, reconstructions show long periods of persistently below average river flows during several intervals including much of the 9^th, 12^th, and 13^th centuries.

Other proxy records include the position of tree lines, melting of glaciers and the types of chironomids present. Chironomids are a distinct group of lake flies whose populations and types can be correlated with specific climatic conditions.

All these proxies are consistent in supporting periods of elevated warmth in the medieval period that coincide with periods of severe and widespread drought. The driest episode was in the mid-12^th century and was more extensive and persistent than any modern drought experienced.

One of the casualties of the long drought was the collapse of the Anasazi or Ancestral Pueblo society that had thrived for hundreds of years in the southwest part of North America. A series of megadroughts of the 10th to 13th centuries finally took their toll on the residents and forced them to move.

More recent droughts that may have impacted our ancestors, possibly droving them to migrate, that we can learn about in published records and family stories include: the 1930s Dust Bowl; the Great Plains droughts in the 1890s, 1870s and 1860s; central Europe in the 1840s; 1790s in Australia; 1760s in the British Isles; early 1600s in the American colonies; and the mid-16^th century in Europe.

Drought is a normal, recurrent feature of climate that occurs in virtually all climate zones. Further to that thought, droughts have occurred virtually every year someplace and megadroughts have been experienced at least once per century, not uncommonly more frequently. The Earth will certainly continue to experience them in the future.

One wonders if residents living in the dry southwest region now could move, would they?

 

References and Data Sources

Ancestral Puebloans https://en.wikipedia.org/wiki/Ancestral_Puebloans

Southwestern North American megadrought https://en.wikipedia.org/wiki/Southwestern_North_American_megadrought

The U.S. Drought Monitor (USDM) is a map released every Thursday, showing where drought is and how bad it is across the U.S. and its territories.  https://droughtmonitor.unl.edu/CurrentMap.aspx

The National Integrated Drought Information System (NIDIS) is a multi-agency partnership that coordinates current drought monitoring, forecasting, planning, and information internationally and also historically. https://www.drought.gov/international

The North American Drought Monitor (NADM) is a cooperative effort between drought experts in Canada, Mexico and the United States to monitor drought across the continent on an ongoing basis. https://www.ncei.noaa.gov/access/monitoring/nadm/maps

The Global Drought Information System (GDIS) is a tool for visualizing drought related data across the globe. https://gdis-noaa.hub.arcgis.com/

The Canadian Drought Monitor (CDM) is Canada's official source for the monitoring and reporting of drought nationally. https://agriculture.canada.ca/en/agricultural-production/weather/canadian-drought-monitor

Copernicus is an EU program aimed at developing European drought information services based on satellite Earth Observation and in situ (non-space) data. https://drought.emergency.copernicus.eu/