Fourth National Climate Assessment

November 28, 2018


On Friday, November 23, 2018, the federal government released the Fourth National Climate Assessment covering both the science and potential impacts of climate change. 


We are nearly a fifth of the way through this twenty-first century and climate impacts—impacts predicted years ago—are beginning to become more and more obvious and paints a potentially terrifying future.

Will this future will look back and wonder if we ever personally asked the question: What kind of world do we want to leave to those who come after us, to children who are now growing up? (Laudato Si’ #160)



The report confirms previous scientific data and analysis—that human activities are the primary driver of climate change, particularly as a result of burning of fossil fuels. Seas are acidifying and oceans are rising. Temperatures have steadily climbed for the last several decades with the three warmest years on record being the last three. Globally and nationally, we are experiencing more and more intense storms, longer droughts, and see disease-carrying insects on the move. 

From the best-case to worst-case, each scenario is sobering. Even if we reduce greenhouse gas pollution immediately, the world is subject to a continued rise in temperatures due to emissions already in the atmosphere. Under worst-case scenarios (i.e., we do nothing about greenhouse gas emissions) by the end of this century the planet is completely altered with human suffering at biblical proportions.

The report spares no economic sector and makes the point—as have the U.S. bishops, the Vatican and many other faith groups and climate observers—that the worst impacts will be felt most acutely by already-vulnerable communities. For people of faith, this fact raises profoundly moral questions.

In the impact section of the report (Volume II), the focus is on the economic costs including the already compromised infrastructure in the U.S. It also notes that everything from tourism based on fishing, hunting, water and winter sports to the cultural and economic devastation on indigenous communities, will be impacted.

The report rightly sees the interconnectedness of impacts and events: seemingly isolated events have downstream consequences. For example, the fires in California or the floods in North Carolina this past year displaced tens of thousands of people, destroyed homes and businesses, pulled billions out of federal, state and local budgets to deal with the crisis. In addition, diseases spread more rapidly, food and water resources were compromised, air quality suffered, and so on.

Particularly troubling is what may happen to agricultural and water resources. While some regions of the country could see short-term gains in agricultural productivity, long-term productivity is in jeopardy, especially in farming communities in the Midwest. Very few regions of the country will be untouched by water uncertainty. From coastal flooding and salt-water inundation to drying aquafers, extended droughts and regular torrential rains, nearly every community will be impacted.

Human health is at risk from increased vector-borne illnesses—those that migrate north and those pests that impact our water and food—as well as from poor water and air quality.

The report calls for a renewed and accelerated commitment to both local and regional adaptation as well as national and global mitigation. Investments in infrastructure, regional economic cooperation for adaptation and mitigation strategies can have many co-benefits: protection from climate impacts, cleaner air, better responses to weather-related disasters, community cohesion, ecosystem restoration and job creation, particularly in the renewable energy and energy conservation fields.



Since 1990, when St. John Paul II wrote his world day of peace message on ecology to the 2001 Global Climate Change statement by the U.S. bishops to Laudato Si’, the message from the Catholic Church has been consistent and clear: climate science is accepted by the Catholic Church, is primarily caused by humankind, and we have an obligation to be much better stewards of the gifts God has given us. This includes being especially mindful of the impacts of our neglect on the poor and on future generations.

While this assessment and last month’s dire warning by the Intergovernmental Panel on Climate Change that we have only 12 years to dramatically lower greenhouse gas emissions, Christians, especially, must not give in to despair. Our faith is born of hope and lived in action. We must embrace and act on our belief that we are co-creators with God. We must remind ourselves that we’ve done far too much “tilling” and far too little “keeping” of our planetary resources. We must redouble our efforts to tend this garden and make it fruitful and abundant for all. For those of us in wealthier countries, it means we must be far more mindful of our environmental impact and find ways to reduce that impact, especially in our patterns of consumption. We must humbly admit that we are the ones primarily driving climate change and therefore have an obligation to change direction.

Rising to the challenges we face must begin with prayerful consideration of the beauty of creation and of our behaviors. We must then pivot to action. How can we reduce our environmental impact personally, within our families, our places of work, our churches, and our nation?

Catholic Climate Covenant and its 18 national Catholic partners are here to help. Please make full use of our resources and programs to learn how you can prayerfully and thoughtfully engage in this global effort to reduce the impact of our lifestyles on our common home.

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