Restoring Ecosystem Health Will Fight Climate Change and Allergies

What do itchy eyes, runny noses, and asthma have to do with the weather events you hear about on the TV, or even have experienced personally? It sure seems as if there are more violent and unpredictable storms and severe weather events in recent years.

Most scientists point to global climate change as the underlying cause of the increased frequency and intensity of such events. But regardless of cause, the actual numbers of weather-related disasters, like the tornadoes that blew down the entire community of Joplin, Missouri, are undeniably on the increase. From flooding, to hurricanes and tornadoes, to blizzards, NOAA reported a record-breaking 14 weather events in 2011 that topped a billion dollars in damages. Typically, 2-4 are recorded.

Dollar amounts only tell a fraction of the story. Damage and disruption are not confined to human communities. The same kinds of winds that destroy a town, also blow down tens of thousands of acres of forests. The droughts that destroy agricultural crops, also bake and stress natural communities. After such disturbance, the land is left vulnerable to erosion from hard rains that carry away topsoil, depleting the land and impairing adjacent water bodies. Strong winds likewise mobilize dust, carrying it long distances, contributing to degraded air quality, and exacerbating allergic respiratory illnesses.

Then, after warm rains have watered disturbed lands, conditions are ripe for the establishment of annual weeds. Alas, a large proportion of these annual weeds, so favored under cycles of storm-created disturbance, are prodigious producers of pollen —the bane of allergy sufferers. In croplands also, when extreme weather causes farmers to miss their window to plant crops, the land lies fallow. What flourishes in these fallow lands? The same pollen-producing annual weed species known to wreak havoc with human allergies!

Ragweed, an annual weed notorious for its ubiquitous nature and large releases of wind-dispersed pollen, is one of the plant species experiencing a longer growing season correlated with the warming conditions of the earth. The resulting earlier flowering, as well as longer seasonal growth facilitated by longer and warmer growing seasons, translate to more pollen for a longer period of time, and increased discomfort and suffering for those with allergies. It may also increase the number of sufferers by sensitizing more people. In short, the synergy of land disturbance, disrupted crop cycles, and prolonged growing season is “made to order” for a wide variety of allergen-producing weedy plants like ragweed.

More severe and prolonged precipitation events also lead to increased erosion, particularly on disturbed lands, and significantly more flooding. As floodwaters recede, the residual organic material facilitates increased growth of molds, among the most common human allergens. Water quality is also impaired by runoff that increases when healthy, intact plant communities are absent. In a related health threat, polluted water, warmed during increased ambient temperatures, creates a fertile medium for the growth of pathogens.

Stormwater and sanitary water treatment facilities are often inadequate to meet this challenge from new stresses caused by weather events. Waterborne illnesses, such as the cryptosporidium outbreak in Milwaukee in 1993, can be the debilitating and even lethal, result.