The Trump administration is making it harder to find government information about climate change on the web. If you searched Google for the words “climate change” a little over six months ago, one of the first hits would have been the Environmental Protection Agency’s website.

But that was before April 28, when the agency began systematically dismantling its climate change website, which had survived Democratic and Republican administrations and was a leading source of information on a global problem that the president, as a candidate, labeled “a hoax.”

If you search those words today, a link to the E.P.A. site may not appear until the second or third search results page, and sometimes not even then, depending on your browser settings. The site has fallen in Google’s search results because its address, or URL, no longer directs you to the climate change site or a related page. If you click that link, you’ll be redirected to a notice page that says, “We are currently updating our website to reflect E.P.A.’s priorities under the leadership” of President Trump and Scott Pruitt, the agency’s administrator. That page, in turn, contains a link to an archived version of the E.P.A.’s website.

Well, you might think, at least the old site has been preserved. But the archive is far from complete. A significant number of pages and PDFs are not available, and entire portions of the site, like the Student’s Guide to Global Climate Change, have been left out. Some of these pages and PDFs can no longer be found anywhere within the government’s web presence. The E.P.A. climate-related web pages that are still live continue to provide valuable information, but many links from those pages to other pages have been removed. And now-broken links that previously led to the E.P.A. climate change pages are scattered across federal and nonfederal websites.